<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019f4761-6d1b-77c6-8f95-ae525eabb14f,g:1008d7bd-7eae-4966-a0e7-6a121b751ea4-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item"/>
  <link:roleRef roleURI="http://www.pkoh.com/role/CondensedConsolidatedBalanceSheets" xlink:type="simple" xlink:href="pkoh-20260630.xsd#CondensedConsolidatedBalanceSheets"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/CondensedConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019f4761-6e9f-77f9-9067-6c5ff13769af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019f4761-6e9f-73c2-9dad-67841694ba6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019f4761-6e9f-77f9-9067-6c5ff13769af" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019f4761-6e9f-73c2-9dad-67841694ba6a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019f4761-6e9f-7938-bcbe-67e8288d3571" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019f4761-6e9f-77f9-9067-6c5ff13769af" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019f4761-6e9f-7938-bcbe-67e8288d3571" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019f4761-6e9f-7044-81cb-ba316d3030ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019f4761-6e9f-77f9-9067-6c5ff13769af" xlink:to="loc_us-gaap_InventoryNet_019f4761-6e9f-7044-81cb-ba316d3030ca" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsCurrent_019f4761-6e9f-7806-b025-de8b8c2910aa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_019f4761-6e9f-77f9-9067-6c5ff13769af" xlink:to="loc_us-gaap_OtherAssetsCurrent_019f4761-6e9f-7806-b025-de8b8c2910aa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesNoncurrent_019f4761-6e9f-799f-a678-22adcd39cf23" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndCapitalLeaseObligations_019f4761-6e9f-7808-80a9-6f5d5883b576" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtAndCapitalLeaseObligations"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019f4761-6e9f-799f-a678-22adcd39cf23" xlink:to="loc_us-gaap_DebtAndCapitalLeaseObligations_019f4761-6e9f-7808-80a9-6f5d5883b576" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_019f4761-6e9f-7b6f-a66d-8ac7a36b03ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019f4761-6e9f-799f-a678-22adcd39cf23" xlink:to="loc_us-gaap_OperatingLeaseLiabilityNoncurrent_019f4761-6e9f-7b6f-a66d-8ac7a36b03ec" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_019f4761-6e9f-7b16-9c9e-df1412ce2851" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesNoncurrent_019f4761-6e9f-799f-a678-22adcd39cf23" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_019f4761-6e9f-7b16-9c9e-df1412ce2851" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019f4761-6e9f-7c73-9a21-2930e487709f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:to="loc_us-gaap_AssetsCurrent_019f4761-6e9f-7c73-9a21-2930e487709f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019f4761-6e9f-7d2f-a5ff-3bbb6a3a2036" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_019f4761-6e9f-7d2f-a5ff-3bbb6a3a2036" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset_019f4761-6e9f-7420-b6ba-954bed97efae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:to="loc_us-gaap_OperatingLeaseRightOfUseAsset_019f4761-6e9f-7420-b6ba-954bed97efae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_019f4761-6e9f-75cc-9ff1-09bdc4ee4306" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:to="loc_us-gaap_Goodwill_019f4761-6e9f-75cc-9ff1-09bdc4ee4306" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_019f4761-6e9f-7b5a-97fb-bbf335d0a74b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:to="loc_us-gaap_DefinedBenefitPlanAssetsForPlanBenefitsNoncurrent_019f4761-6e9f-7b5a-97fb-bbf335d0a74b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019f4761-6e9f-7366-8277-8b973f5f7b72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_019f4761-6e9f-77c2-8f1f-57ff1ef3e931" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_019f4761-6e9f-7366-8277-8b973f5f7b72" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7524-a2dc-3844f79a06d1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableTradeCurrent_019f4761-6e9f-7c07-8551-0fedd1989ad0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableTradeCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7524-a2dc-3844f79a06d1" xlink:to="loc_us-gaap_AccountsPayableTradeCurrent_019f4761-6e9f-7c07-8551-0fedd1989ad0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtCurrent_019f4761-6e9f-76ec-98d2-2045d833d22b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7524-a2dc-3844f79a06d1" xlink:to="loc_us-gaap_DebtCurrent_019f4761-6e9f-76ec-98d2-2045d833d22b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent_019f4761-6e9f-7da0-a68f-f9e5d1cb638d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7524-a2dc-3844f79a06d1" xlink:to="loc_us-gaap_OperatingLeaseLiabilityCurrent_019f4761-6e9f-7da0-a68f-f9e5d1cb638d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019f4761-6e9f-7a90-a9ca-5aafcc05d504" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7524-a2dc-3844f79a06d1" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_019f4761-6e9f-7a90-a9ca-5aafcc05d504" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7921-9fec-55d1a94870e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019f4761-6e9f-7ad6-9de8-13a654074ede" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7921-9fec-55d1a94870e5" xlink:to="loc_us-gaap_StockholdersEquity_019f4761-6e9f-7ad6-9de8-13a654074ede" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterest_019f4761-6e9f-75e4-aa93-752397e37af0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterest"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7921-9fec-55d1a94870e5" xlink:to="loc_us-gaap_MinorityInterest_019f4761-6e9f-75e4-aa93-752397e37af0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019f4761-6e9f-7d16-af8a-9b0aa0a4fa09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7ff2-8bb9-19939f5db8fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019f4761-6e9f-7d16-af8a-9b0aa0a4fa09" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7ff2-8bb9-19939f5db8fa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesNoncurrent_019f4761-6e9f-79b5-8458-eb42bb9e2d45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesNoncurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019f4761-6e9f-7d16-af8a-9b0aa0a4fa09" xlink:to="loc_us-gaap_LiabilitiesNoncurrent_019f4761-6e9f-79b5-8458-eb42bb9e2d45" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7c3b-96bd-fd482209af2f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_019f4761-6e9f-7d16-af8a-9b0aa0a4fa09" xlink:to="loc_us-gaap_LiabilitiesCurrent_019f4761-6e9f-7c3b-96bd-fd482209af2f" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/CondensedConsolidatedStatementsofIncomeUnaudited" xlink:type="simple" xlink:href="pkoh-20260630.xsd#CondensedConsolidatedStatementsofIncomeUnaudited"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/CondensedConsolidatedStatementsofIncomeUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_019f4761-6e9f-7473-9817-c2809935dd9f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_019f4761-6e9f-7cf4-bb7b-25fa2ff06e49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_EarningsPerShareBasic_019f4761-6e9f-7473-9817-c2809935dd9f" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_019f4761-6e9f-7cf4-bb7b-25fa2ff06e49" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_019f4761-6e9f-798e-a3f0-b524f74b155a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_EarningsPerShareBasic_019f4761-6e9f-7473-9817-c2809935dd9f" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_019f4761-6e9f-798e-a3f0-b524f74b155a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_019f4761-6e9f-78f0-80a4-29d2940215ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7efb-9590-cc90682714b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperations_019f4761-6e9f-78f0-80a4-29d2940215ff" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7efb-9590-cc90682714b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_019f4761-6e9f-7a32-906a-ffad25e0b1a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperations_019f4761-6e9f-78f0-80a4-29d2940215ff" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_019f4761-6e9f-7a32-906a-ffad25e0b1a9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-7cc5-abde-2dc702f07524" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7533-8b3b-a9323b0187c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-7cc5-abde-2dc702f07524" xlink:to="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7533-8b3b-a9323b0187c8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent_019f4761-6e9f-7a37-941d-8085ac629170" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-7cc5-abde-2dc702f07524" xlink:to="loc_us-gaap_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponent_019f4761-6e9f-7a37-941d-8085ac629170" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019f4761-6e9f-7fa0-9946-438d7e2caaf7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-7cc5-abde-2dc702f07524" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019f4761-6e9f-7fa0-9946-438d7e2caaf7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7099-896a-58b2629dfa33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-783b-8497-36440a12e2d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7099-896a-58b2629dfa33" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-783b-8497-36440a12e2d3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019f4761-6e9f-7d2f-ba2b-386cedd43ed1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-7099-896a-58b2629dfa33" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019f4761-6e9f-7d2f-ba2b-386cedd43ed1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019f4761-6e9f-75d7-92fb-11cb8547b69b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_019f4761-6e9f-7579-8158-a327ed8fb827" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019f4761-6e9f-75d7-92fb-11cb8547b69b" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperations_019f4761-6e9f-7579-8158-a327ed8fb827" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_019f4761-6e9f-7da8-ab95-50d4b90a4791" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_019f4761-6e9f-75d7-92fb-11cb8547b69b" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_019f4761-6e9f-7da8-ab95-50d4b90a4791" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_019f4761-6e9f-7957-9c6d-65c41b1db5db" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_019f4761-6e9f-75cb-a409-d867fc036b21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_EarningsPerShareDiluted_019f4761-6e9f-7957-9c6d-65c41b1db5db" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_019f4761-6e9f-75cb-a409-d867fc036b21" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_019f4761-6e9f-70b0-aec4-fb15e5ce303f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_EarningsPerShareDiluted_019f4761-6e9f-7957-9c6d-65c41b1db5db" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_019f4761-6e9f-70b0-aec4-fb15e5ce303f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7206-ad81-d2fc12ee86f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019f4761-6e9f-7c7f-a3f4-365265b09c18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7206-ad81-d2fc12ee86f1" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019f4761-6e9f-7c7f-a3f4-365265b09c18" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_019f4761-6e9f-74f5-9825-fb2972dc2013" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7206-ad81-d2fc12ee86f1" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_019f4761-6e9f-74f5-9825-fb2972dc2013" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019f4761-6e9f-7e2e-b610-0d467bbd0bd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7206-ad81-d2fc12ee86f1" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_019f4761-6e9f-7e2e-b610-0d467bbd0bd4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_RestructuringAndOtherSpecialCharges_019f4761-6e9f-78cc-a739-d014a01ce387" xlink:href="pkoh-20260630.xsd#pkoh_RestructuringAndOtherSpecialCharges"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7206-ad81-d2fc12ee86f1" xlink:to="loc_pkoh_RestructuringAndOtherSpecialCharges_019f4761-6e9f-78cc-a739-d014a01ce387" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/CondensedConsolidatedStatementsofComprehensiveIncomeUnaudited" xlink:type="simple" xlink:href="pkoh-20260630.xsd#CondensedConsolidatedStatementsofComprehensiveIncomeUnaudited"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/CondensedConsolidatedStatementsofComprehensiveIncomeUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019f4761-6e9f-75a6-9022-8c2fedebc835" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_019f4761-6e9f-7eff-862b-60dc6af8699f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019f4761-6e9f-75a6-9022-8c2fedebc835" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_019f4761-6e9f-7eff-862b-60dc6af8699f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019f4761-6e9f-78e5-ad53-fd8c7d7b8e52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019f4761-6e9f-75a6-9022-8c2fedebc835" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_019f4761-6e9f-78e5-ad53-fd8c7d7b8e52" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019f921f-b6f1-7a96-aa99-ef39296115fd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019f4761-6e9f-75a6-9022-8c2fedebc835" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_019f921f-b6f1-7a96-aa99-ef39296115fd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-75eb-a2d3-61aeb947041a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019f4761-6e9f-7f35-b851-7f9dd794c208" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-75eb-a2d3-61aeb947041a" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_019f4761-6e9f-7f35-b851-7f9dd794c208" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019f4761-6e9f-7383-8df0-9b211a1fa221" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-75eb-a2d3-61aeb947041a" xlink:to="loc_us-gaap_ProfitLoss_019f4761-6e9f-7383-8df0-9b211a1fa221" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_019f4761-6e9f-7850-ae03-23da3c30b33d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-78ba-b757-f45e45263b42" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019f4761-6e9f-7850-ae03-23da3c30b33d" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-78ba-b757-f45e45263b42" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_019f4761-6e9f-7747-ad2a-23706a669e7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_019f4761-6e9f-7850-ae03-23da3c30b33d" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_019f4761-6e9f-7747-ad2a-23706a669e7c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/CondensedConsolidatedStatementsofCashFlowsUnaudited" xlink:type="simple" xlink:href="pkoh-20260630.xsd#CondensedConsolidatedStatementsofCashFlowsUnaudited"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/CondensedConsolidatedStatementsofCashFlowsUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019f4761-6e9f-7023-a3bd-7452d59f522b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019f4761-6e9f-7632-8468-3b08ec0d9f51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_019f4761-6e9f-7023-a3bd-7452d59f522b" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019f4761-6e9f-7632-8468-3b08ec0d9f51" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_019f4761-6e9f-73ad-b658-8320d3a91e45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019f4761-6e9f-75fe-86a0-e66b0705a9ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_019f4761-6e9f-73ad-b658-8320d3a91e45" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_019f4761-6e9f-75fe-86a0-e66b0705a9ed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInDiscontinuedOperations_019f4761-6e9f-70bb-b990-5bb34d7bb67c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInDiscontinuedOperations"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_019f4761-6e9f-7b01-bdbf-c0aebfd7a6cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInDiscontinuedOperations_019f4761-6e9f-70bb-b990-5bb34d7bb67c" xlink:to="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_019f4761-6e9f-7b01-bdbf-c0aebfd7a6cc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromRepaymentsOfLinesOfCredit_019f4761-6e9f-758d-8965-07824c325408" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromRepaymentsOfLinesOfCredit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:to="loc_us-gaap_ProceedsFromRepaymentsOfLinesOfCredit_019f4761-6e9f-758d-8965-07824c325408" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfOtherDebt_019f4761-6e9f-7359-b103-b4d1b320decd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfOtherDebt"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:to="loc_us-gaap_RepaymentsOfOtherDebt_019f4761-6e9f-7359-b103-b4d1b320decd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt_019f4761-6e9f-7a3a-8d59-8229bedbf540" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt_019f4761-6e9f-7a3a-8d59-8229bedbf540" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_ProceedsFromPaymentsOnFinanceLeaseFacilitiesNet_019f4761-6e9f-712d-8cda-0eb01d366e76" xlink:href="pkoh-20260630.xsd#pkoh_ProceedsFromPaymentsOnFinanceLeaseFacilitiesNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:to="loc_pkoh_ProceedsFromPaymentsOnFinanceLeaseFacilitiesNet_019f4761-6e9f-712d-8cda-0eb01d366e76" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_019f4761-6e9f-7f19-817f-1b42201808ed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfDividends"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:to="loc_us-gaap_PaymentsOfDividends_019f4761-6e9f-7f19-817f-1b42201808ed" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019f9225-d54d-7b6c-9d2e-174b26b8fdde" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-777e-a323-f9cbed7cc2fc" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019f9225-d54d-7b6c-9d2e-174b26b8fdde" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019f4761-6e9f-757e-bd06-69fcf8a1a197" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7170-9846-c5f7bab60ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019f4761-6e9f-757e-bd06-69fcf8a1a197" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7170-9846-c5f7bab60ad7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_019f4761-6e9f-76d5-96e9-341328efe837" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019f4761-6e9f-757e-bd06-69fcf8a1a197" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_019f4761-6e9f-76d5-96e9-341328efe837" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-70e9-bae9-4a9094d289ef" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019f4761-6e9f-757e-bd06-69fcf8a1a197" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_019f4761-6e9f-70e9-bae9-4a9094d289ef" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019f4761-6e9f-7cc5-a94d-0c94d3f9b209" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019f4761-6e9f-757e-bd06-69fcf8a1a197" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019f4761-6e9f-7cc5-a94d-0c94d3f9b209" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInDiscontinuedOperations_019f4761-6e9f-717e-823f-67c0cf891b15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInDiscontinuedOperations"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_019f4761-6e9f-757e-bd06-69fcf8a1a197" xlink:to="loc_us-gaap_NetCashProvidedByUsedInDiscontinuedOperations_019f4761-6e9f-717e-823f-67c0cf891b15" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-70e4-a291-23c414e283f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_019f4761-6e9f-70e4-a291-23c414e283f8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019f4761-6e9f-7be4-9bdb-51bf773e056b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019f4761-6e9f-7be4-9bdb-51bf773e056b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_019f4761-6e9f-7bcb-adde-dacf56bd1a94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_ShareBasedCompensation_019f4761-6e9f-7bcb-adde-dacf56bd1a94" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019f4761-6e9f-7073-8377-7ae2e9996389" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_019f4761-6e9f-7073-8377-7ae2e9996389" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_019f4761-6e9f-7e06-a8e6-4eff571d4f36" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_019f4761-6e9f-7e06-a8e6-4eff571d4f36" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_019f4761-6e9f-7754-ad1a-729589ceb3e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_019f4761-6e9f-7754-ad1a-729589ceb3e2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_019f4761-6e9f-7a3b-a3ad-6c98fdd99c87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_019f4761-6e9f-7a3b-a3ad-6c98fdd99c87" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_019f4761-6e9f-7edb-80f2-4bd6af42a812" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherOperatingActivitiesCashFlowStatement"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_019f4761-6e9f-7e5c-bf48-b4879acb5297" xlink:to="loc_us-gaap_OtherOperatingActivitiesCashFlowStatement_019f4761-6e9f-7edb-80f2-4bd6af42a812" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromRepaymentsOfLinesOfCredit_019f4761-6e9f-7c21-aa3b-d2b8b7b7d2ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromRepaymentsOfLinesOfCredit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:to="loc_us-gaap_ProceedsFromRepaymentsOfLinesOfCredit_019f4761-6e9f-7c21-aa3b-d2b8b7b7d2ad" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfOtherDebt_019f4761-6e9f-7f1a-9801-c8545a0496ae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfOtherDebt"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:to="loc_us-gaap_RepaymentsOfOtherDebt_019f4761-6e9f-7f1a-9801-c8545a0496ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt_019f4761-6e9f-7b6e-86b2-583a9ab74b35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfOtherLongTermDebt_019f4761-6e9f-7b6e-86b2-583a9ab74b35" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_ProceedsFromPaymentsOnFinanceLeaseFacilitiesNet_019f4761-6e9f-7d4d-8ef9-2a5bbf209b30" xlink:href="pkoh-20260630.xsd#pkoh_ProceedsFromPaymentsOnFinanceLeaseFacilitiesNet"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:to="loc_pkoh_ProceedsFromPaymentsOnFinanceLeaseFacilitiesNet_019f4761-6e9f-7d4d-8ef9-2a5bbf209b30" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividends_019f4761-6e9f-7362-89f6-47278c92cf43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfDividends"/>
    <link:calculationArc order="5" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:to="loc_us-gaap_PaymentsOfDividends_019f4761-6e9f-7362-89f6-47278c92cf43" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019f9225-58ad-7f2e-8e17-93610e7d5243" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_019f4761-6e9f-7726-9b99-55cbca5c606d" xlink:to="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_019f9225-58ad-7f2e-8e17-93610e7d5243" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/SegmentsScheduleofResultsbyBusinessSegmentDetails" xlink:type="simple" xlink:href="pkoh-20260630.xsd#SegmentsScheduleofResultsbyBusinessSegmentDetails"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/SegmentsScheduleofResultsbyBusinessSegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7fdb-a137-62edff3ef54e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_SegmentOperatingIncomeLoss_019f4761-6e9f-7abe-a0b6-dc71e8af7f21" xlink:href="pkoh-20260630.xsd#pkoh_SegmentOperatingIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7fdb-a137-62edff3ef54e" xlink:to="loc_pkoh_SegmentOperatingIncomeLoss_019f4761-6e9f-7abe-a0b6-dc71e8af7f21" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_CorporateExpenses_019f4761-6e9f-7bf6-b923-cd1dffd123ba" xlink:href="pkoh-20260630.xsd#pkoh_CorporateExpenses"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7fdb-a137-62edff3ef54e" xlink:to="loc_pkoh_CorporateExpenses_019f4761-6e9f-7bf6-b923-cd1dffd123ba" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_CorporateRestructuringAndOtherSpecialCharges_019f4761-6e9f-7422-8319-17577196c515" xlink:href="pkoh-20260630.xsd#pkoh_CorporateRestructuringAndOtherSpecialCharges"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-7fdb-a137-62edff3ef54e" xlink:to="loc_pkoh_CorporateRestructuringAndOtherSpecialCharges_019f4761-6e9f-7422-8319-17577196c515" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_SegmentOperatingIncomeLoss_019f4761-6e9f-746b-abc9-973d9cf0f2d1" xlink:href="pkoh-20260630.xsd#pkoh_SegmentOperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019f4761-6e9f-7407-a09c-faea83b3d61b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_pkoh_SegmentOperatingIncomeLoss_019f4761-6e9f-746b-abc9-973d9cf0f2d1" xlink:to="loc_us-gaap_GrossProfit_019f4761-6e9f-7407-a09c-faea83b3d61b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_SellingGeneralAndAdministrativeExpenseAdjusted_019f4761-6e9f-7b8e-a11a-312e822b1dbc" xlink:href="pkoh-20260630.xsd#pkoh_SellingGeneralAndAdministrativeExpenseAdjusted"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_pkoh_SegmentOperatingIncomeLoss_019f4761-6e9f-746b-abc9-973d9cf0f2d1" xlink:to="loc_pkoh_SellingGeneralAndAdministrativeExpenseAdjusted_019f4761-6e9f-7b8e-a11a-312e822b1dbc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_RestructuringAndOtherSpecialChargesAdjusted_019f4761-6e9f-7185-b09c-3ce706dea1db" xlink:href="pkoh-20260630.xsd#pkoh_RestructuringAndOtherSpecialChargesAdjusted"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_pkoh_SegmentOperatingIncomeLoss_019f4761-6e9f-746b-abc9-973d9cf0f2d1" xlink:to="loc_pkoh_RestructuringAndOtherSpecialChargesAdjusted_019f4761-6e9f-7185-b09c-3ce706dea1db" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-734b-981c-9e9b2b59cb32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-773e-9731-182c223c394a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-734b-981c-9e9b2b59cb32" xlink:to="loc_us-gaap_OperatingIncomeLoss_019f4761-6e9f-773e-9731-182c223c394a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_pkoh_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponentAdjusted_019f4761-6e9f-7c43-88e5-ff107d99bd98" xlink:href="pkoh-20260630.xsd#pkoh_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponentAdjusted"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-734b-981c-9e9b2b59cb32" xlink:to="loc_pkoh_NetPeriodicDefinedBenefitsExpenseReversalOfExpenseExcludingServiceCostComponentAdjusted_019f4761-6e9f-7c43-88e5-ff107d99bd98" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019f4761-6e9f-7917-9f21-c4af170d5353" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_019f4761-6e9f-734b-981c-9e9b2b59cb32" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019f4761-6e9f-7917-9f21-c4af170d5353" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019f4761-6e9f-7d04-a21f-027e69ebde9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019f4761-6e9f-78b5-b96a-cf8cd73ccb0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_019f4761-6e9f-7d04-a21f-027e69ebde9d" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019f4761-6e9f-78b5-b96a-cf8cd73ccb0d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_019f4761-6e9f-7113-a4e0-e47d82609fce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_019f4761-6e9f-7d04-a21f-027e69ebde9d" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_019f4761-6e9f-7113-a4e0-e47d82609fce" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/InventoriesDetails" xlink:type="simple" xlink:href="pkoh-20260630.xsd#InventoriesDetails"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/InventoriesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_019f4761-6e9f-75ce-9bcb-c1745e57c8e5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryFinishedGoods_019f4761-6e9f-774b-9446-7ea8e1d73f73" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryFinishedGoods"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019f4761-6e9f-75ce-9bcb-c1745e57c8e5" xlink:to="loc_us-gaap_InventoryFinishedGoods_019f4761-6e9f-774b-9446-7ea8e1d73f73" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryWorkInProcess_019f4761-6e9f-7f4b-89c7-20ab729553e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWorkInProcess"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019f4761-6e9f-75ce-9bcb-c1745e57c8e5" xlink:to="loc_us-gaap_InventoryWorkInProcess_019f4761-6e9f-7f4b-89c7-20ab729553e0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryRawMaterialsAndSupplies_019f4761-6e9f-74db-bb3f-f8e48700601e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryRawMaterialsAndSupplies"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_019f4761-6e9f-75ce-9bcb-c1745e57c8e5" xlink:to="loc_us-gaap_InventoryRawMaterialsAndSupplies_019f4761-6e9f-74db-bb3f-f8e48700601e" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/FinancingArrangementsScheduleofLongtermDebtDetails" xlink:type="simple" xlink:href="pkoh-20260630.xsd#FinancingArrangementsScheduleofLongtermDebtDetails"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/FinancingArrangementsScheduleofLongtermDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019f4761-6e9f-7dd7-9dd8-78a3e08ce8bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019f4761-6e9f-7c9c-8104-b0c6be66460f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019f4761-6e9f-7dd7-9dd8-78a3e08ce8bf" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019f4761-6e9f-7c9c-8104-b0c6be66460f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_019f4761-6e9f-7fb6-8872-3dd246adadd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019f4761-6e9f-7dd7-9dd8-78a3e08ce8bf" xlink:to="loc_us-gaap_FinanceLeaseLiability_019f4761-6e9f-7fb6-8872-3dd246adadd8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLongTermDebt_019f4761-6e9f-735f-a30b-c51ff9b00fc9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLongTermDebt"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_019f4761-6e9f-7dd7-9dd8-78a3e08ce8bf" xlink:to="loc_us-gaap_OtherLongTermDebt_019f4761-6e9f-735f-a30b-c51ff9b00fc9" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/PensionandPostretirementBenefitsDetails" xlink:type="simple" xlink:href="pkoh-20260630.xsd#PensionandPostretirementBenefitsDetails"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/PensionandPostretirementBenefitsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019f4761-6e9f-7b05-a2c1-4a9295b00fd9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost_019f4761-6e9f-7f07-bb38-9258568c4499" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanServiceCost"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019f4761-6e9f-7b05-a2c1-4a9295b00fd9" xlink:to="loc_us-gaap_DefinedBenefitPlanServiceCost_019f4761-6e9f-7f07-bb38-9258568c4499" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost_019f4761-6e9f-71a5-ac0c-4cb7aed0ec83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanInterestCost"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019f4761-6e9f-7b05-a2c1-4a9295b00fd9" xlink:to="loc_us-gaap_DefinedBenefitPlanInterestCost_019f4761-6e9f-71a5-ac0c-4cb7aed0ec83" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_019f4761-6e9f-7977-a044-25fd2b9ae4d9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019f4761-6e9f-7b05-a2c1-4a9295b00fd9" xlink:to="loc_us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_019f4761-6e9f-7977-a044-25fd2b9ae4d9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DefinedBenefitPlanActuarialGainLossImmediateRecognitionAsComponentInNetPeriodicBenefitCostCredit_019f5f6e-535a-7333-b4ca-16ca19ec88f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanActuarialGainLossImmediateRecognitionAsComponentInNetPeriodicBenefitCostCredit"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_019f4761-6e9f-7b05-a2c1-4a9295b00fd9" xlink:to="loc_us-gaap_DefinedBenefitPlanActuarialGainLossImmediateRecognitionAsComponentInNetPeriodicBenefitCostCredit_019f5f6e-535a-7333-b4ca-16ca19ec88f4" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.pkoh.com/role/WeightedAverageNumberofSharesUsedinComputingEarningsPerShareScheduleofWeightedAverageNumberofSharesUsedinComputingEarningsPerShareDetails" xlink:type="simple" xlink:href="pkoh-20260630.xsd#WeightedAverageNumberofSharesUsedinComputingEarningsPerShareScheduleofWeightedAverageNumberofSharesUsedinComputingEarningsPerShareDetails"/>
  <link:calculationLink xlink:role="http://www.pkoh.com/role/WeightedAverageNumberofSharesUsedinComputingEarningsPerShareScheduleofWeightedAverageNumberofSharesUsedinComputingEarningsPerShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019f4761-6e9f-7dca-b491-0794f9826e53" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019f4761-6e9f-78c5-83d6-b0d50b72de04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019f4761-6e9f-7dca-b491-0794f9826e53" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019f4761-6e9f-78c5-83d6-b0d50b72de04" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_019f4761-6e9f-7801-9c56-7e13d33d4571" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019f4761-6e9f-7dca-b491-0794f9826e53" xlink:to="loc_us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_019f4761-6e9f-7801-9c56-7e13d33d4571" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
