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  <xs:element id="spxc_MatureWithinOneYearMember" abstract="true" name="MatureWithinOneYearMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_DebtRollForward" abstract="true" name="DebtRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="spxc_RestructuringAndIntegrationReservesTranslationAndOtherAdjustment" abstract="false" name="RestructuringAndIntegrationReservesTranslationAndOtherAdjustment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_DebtInstrumentCollateralPercentageofCapitalStockofDomesticSubsidiaries" abstract="false" name="DebtInstrumentCollateralPercentageofCapitalStockofDomesticSubsidiaries" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="spxc_DBTTechnologiesMember" abstract="true" name="DBTTechnologiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_PackageAndProcessCoolingEquipmentAndServicesAndEngineeredAirQualitySolutionsMember" abstract="true" name="PackageAndProcessCoolingEquipmentAndServicesAndEngineeredAirQualitySolutionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_AcquisitionsAndDiscontinuedOperationsAbstract" abstract="true" name="AcquisitionsAndDiscontinuedOperationsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="spxc_ALLOtherDiscontinuedOperationsMember" abstract="true" name="ALLOtherDiscontinuedOperationsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_GrossGoodwillRelatedToForeignCurrencyTranslationAndOther" abstract="false" name="GrossGoodwillRelatedToForeignCurrencyTranslationAndOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_CashAndCashEquivalentsIncludedInAssetsOfAbandonedEntities" abstract="false" name="CashAndCashEquivalentsIncludedInAssetsOfAbandonedEntities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_TriggeringEventAxis" abstract="true" name="TriggeringEventAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="spxc_BlackScholesOptionPricingModelTable" abstract="true" name="BlackScholesOptionPricingModelTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="spxc_PerformanceSharesRestrictedStockandRestrictedStockUnitsMember" abstract="true" name="PerformanceSharesRestrictedStockandRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_SeniorCreditAgreementRange3Member" abstract="true" name="SeniorCreditAgreementRange3Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_NumberOfLargePowerProjects" abstract="false" name="NumberOfLargePowerProjects" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="spxc_NumberOfDisputes" abstract="false" name="NumberOfDisputes" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="spxc_SensorsSoftwareIncMember" abstract="true" name="SensorsSoftwareIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_SPXHeatTransferBusinessMember" abstract="true" name="SPXHeatTransferBusinessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_DebtInstrumentCollateralPercentageOfNonVotingCapitalStockOfMaterialFirstTierForeignSubsidiaries" abstract="false" name="DebtInstrumentCollateralPercentageOfNonVotingCapitalStockOfMaterialFirstTierForeignSubsidiaries" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="spxc_AccumulatedImpairmentsRelatedToForeignCurrencyTranslationAndOtherAdjustments" abstract="false" name="AccumulatedImpairmentsRelatedToForeignCurrencyTranslationAndOtherAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_TAMorrisonCoIncTAMCOMember" abstract="true" name="TAMorrisonCoIncTAMCOMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_TransformerSolutionsMember" abstract="true" name="TransformerSolutionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_UnrecognizedTaxBenefitsNet" abstract="false" name="UnrecognizedTaxBenefitsNet" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_PaymentForDivestiture" abstract="false" name="PaymentForDivestiture" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_GoodwillRelatedToForeignCurrencyTranslationAndOther" abstract="false" name="GoodwillRelatedToForeignCurrencyTranslationAndOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentGross" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentGross" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_CurrentRevolvingSPXFacilitiesMember" abstract="true" name="CurrentRevolvingSPXFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_IncreaseDecreaseinContractwithCustomersNet" abstract="false" name="IncreaseDecreaseinContractwithCustomersNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_SecuredOvernightFinancingRateSOFRPeriodTwoMember" abstract="true" name="SecuredOvernightFinancingRateSOFRPeriodTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_LegacySPXMember" abstract="true" name="LegacySPXMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_DBTTechnologiesIncludingCTAWriteOffMember" abstract="true" name="DBTTechnologiesIncludingCTAWriteOffMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_OtherLongTermLiabilitiesMember" abstract="true" name="OtherLongTermLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_NumberOfCountriesInWhichEntitySellsItsProductsAndServices" abstract="false" name="NumberOfCountriesInWhichEntitySellsItsProductsAndServices" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="spxc_ScheduleOfDebtInstrumentsTable" abstract="true" name="ScheduleOfDebtInstrumentsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="spxc_SecuredOvernightFinancingRateSOFRPeriodThreeMember" abstract="true" name="SecuredOvernightFinancingRateSOFRPeriodThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_GainContingencyUnrecordedAmountCurrentProcceding" abstract="false" name="GainContingencyUnrecordedAmountCurrentProcceding" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityPeriodBasedOnHistoricalVolatility" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityPeriodBasedOnHistoricalVolatility" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="spxc_DebtInstrumentCollateralPercentageofCapitalStockofMaterialFirstTierForeignSubsidiaries" abstract="false" name="DebtInstrumentCollateralPercentageofCapitalStockofMaterialFirstTierForeignSubsidiaries" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="spxc_ScheduleofRestructuringandIntegratedLiabilitiesTableTextBlock" abstract="false" name="ScheduleofRestructuringandIntegratedLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType"/>
  <xs:element id="spxc_SPXPostretirementPlansMember" abstract="true" name="SPXPostretirementPlansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_ULCRoboticsMember" abstract="true" name="ULCRoboticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_InternationalTowerLightingLLCMember" abstract="true" name="InternationalTowerLightingLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_BlackScholesOptionPricingModelLineItems" abstract="true" name="BlackScholesOptionPricingModelLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="spxc_ASPEQParentHoldingsIncMember" abstract="true" name="ASPEQParentHoldingsIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_DefinedBenefitPlanBenefitObligationLossOnSettlement" abstract="false" name="DefinedBenefitPlanBenefitObligationLossOnSettlement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_RepaymentsUnderTradeReceivablesAgreement" abstract="false" name="RepaymentsUnderTradeReceivablesAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_DetectionandMeasurementReportableSegmentMember" abstract="true" name="DetectionandMeasurementReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_MHIAprilAndJuly2019ClaimsMember" abstract="true" name="MHIAprilAndJuly2019ClaimsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_IncreaseDecreaseinAccountsReceivableNet" abstract="false" name="IncreaseDecreaseinAccountsReceivableNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_MHIMember" abstract="true" name="MHIMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_MHIAdditionalClaimsMember" abstract="true" name="MHIAdditionalClaimsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_BoilerComfortHeatingAndVentilationMember" abstract="true" name="BoilerComfortHeatingAndVentilationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_CommunicationTechnologiesObstructionLightingAndFareFareCollectionSystemsMember" abstract="true" name="CommunicationTechnologiesObstructionLightingAndFareFareCollectionSystemsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_LiabilitiesOfAbandonedEntities" abstract="false" name="LiabilitiesOfAbandonedEntities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_BuildingsAndLeaseholdImprovementsMember" abstract="true" name="BuildingsAndLeaseholdImprovementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_BorrowingUnderTradeReceivablesAgreement" abstract="false" name="BorrowingUnderTradeReceivablesAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_CurrentSPXTermLoanFacilitiesMember" abstract="true" name="CurrentSPXTermLoanFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_DisposalGroupIncludingDiscontinuedOperationAccumulatedDepreciation" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationAccumulatedDepreciation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_APICShareBasedPaymentArrangementLongTermIncentiveCompensationExpense" abstract="false" name="APICShareBasedPaymentArrangementLongTermIncentiveCompensationExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_DemandBondsMember" abstract="true" name="DemandBondsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_BondsUponCompletionOfCertainAdministrativeMilestonesMemberMember" abstract="true" name="BondsUponCompletionOfCertainAdministrativeMilestonesMemberMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_TriggeringEventDomain" abstract="true" name="TriggeringEventDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
