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  <xs:element id="spxc_DisposalGroupIncludingDiscontinuedOperationDebtContributed" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationDebtContributed" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_HVACReportableSegmentMember" abstract="true" name="HVACReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_TriggeringEventAxis" abstract="true" name="TriggeringEventAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="spxc_TriggeringEventDomain" abstract="true" name="TriggeringEventDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_RetentionAgreementsMember" abstract="true" name="RetentionAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_HeatTransferMember" abstract="true" name="HeatTransferMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_EmployeeRetentionAgreementTerm" abstract="false" name="EmployeeRetentionAgreementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="spxc_NumberOfLargePowerProjects" abstract="false" name="NumberOfLargePowerProjects" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="spxc_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAcquiredIncludingGoodwill" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAcquiredIncludingGoodwill" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsAbstract" abstract="true" name="BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="spxc_BusinessAcquisitionProFormaEarningsPerShareAbstract" abstract="true" name="BusinessAcquisitionProFormaEarningsPerShareAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <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_DisposalGroupIncludingDiscontinuedOperationContractLiabilitiesCurrent" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationContractLiabilitiesCurrent" nillable="true" xbrli:periodType="instant" 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_PackageAndProcessCoolingEquipmentAndServicesAndEngineeredAirMovementAndHandlingSolutionsMember" abstract="true" name="PackageAndProcessCoolingEquipmentAndServicesAndEngineeredAirMovementAndHandlingSolutionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_HydronicHeatingElectricalHeatingAndVentilationMember" abstract="true" name="HydronicHeatingElectricalHeatingAndVentilationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_UndergroundLocatorsInspectionAndRehabilitationEquipmentAndRoboticSystemsMember" abstract="true" name="UndergroundLocatorsInspectionAndRehabilitationEquipmentAndRoboticSystemsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_CommunicationTechnologiesAidsToNavigationAndTransportationSystemsMember" abstract="true" name="CommunicationTechnologiesAidsToNavigationAndTransportationSystemsMember" 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_IncreaseDecreaseinContractwithCustomerAssetNetCurrent" abstract="false" name="IncreaseDecreaseinContractwithCustomerAssetNetCurrent" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_IncreaseDecreaseinContractwithCustomerLiabilityCurrent" abstract="false" name="IncreaseDecreaseinContractwithCustomerLiabilityCurrent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_IncreaseDecreaseinContractwithCustomerLiabilityNoncurrent" abstract="false" name="IncreaseDecreaseinContractwithCustomerLiabilityNoncurrent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_ContractwithCustomersNet" abstract="false" name="ContractwithCustomersNet" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_NumberOfCountriesInWhichEntitySellsItsProductsAndServices" abstract="false" name="NumberOfCountriesInWhichEntitySellsItsProductsAndServices" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="spxc_SegmentReportingMember" abstract="true" name="SegmentReportingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_OtherForeignCountriesMember" abstract="true" name="OtherForeignCountriesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_LongLivedAssetsOfContinuingOperations" abstract="false" name="LongLivedAssetsOfContinuingOperations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_LongLivedAssetsOfDiscontinuedOperations" abstract="false" name="LongLivedAssetsOfDiscontinuedOperations" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_ThermolecMember" abstract="true" name="ThermolecMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_GoodwillResultingFromBusinessCombinationsAccumulatedImpairment" abstract="false" name="GoodwillResultingFromBusinessCombinationsAccumulatedImpairment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <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_AccumulatedImpairmentsRelatedToForeignCurrencyTranslationAndOtherAdjustments" abstract="false" name="AccumulatedImpairmentsRelatedToForeignCurrencyTranslationAndOtherAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" 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_ASPEQHeatingGroupMember" abstract="true" name="ASPEQHeatingGroupMember" 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_DefinedBenefitPlanBenefitObligationLossOnSettlement" abstract="false" name="DefinedBenefitPlanBenefitObligationLossOnSettlement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_ScheduleOfDebtInstrumentsTable" abstract="true" name="ScheduleOfDebtInstrumentsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="spxc_SeniorCreditFacilityMember" abstract="true" name="SeniorCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_CurrentSPXTermLoanFacilitiesMember" abstract="true" name="CurrentSPXTermLoanFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_OtherBorrowingsMember" abstract="true" name="OtherBorrowingsMember" 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_DebtInstrumentPeriodicPaymentPercentageOfPrincipal" abstract="false" name="DebtInstrumentPeriodicPaymentPercentageOfPrincipal" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="spxc_CurrentSPXTermLoanFacilityMember" abstract="true" name="CurrentSPXTermLoanFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_FinancialLettersOfCreditMember" abstract="true" name="FinancialLettersOfCreditMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_NonFinancialLettersOfCreditMember" abstract="true" name="NonFinancialLettersOfCreditMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_NonUSExposureMember" abstract="true" name="NonUSExposureMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_BilateralForeignCreditInstrumentFacilityMember" abstract="true" name="BilateralForeignCreditInstrumentFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_DomesticRevolvingLoanFacilityMember" abstract="true" name="DomesticRevolvingLoanFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_ForeignCreditInstrumentFacilitiesMember" abstract="true" name="ForeignCreditInstrumentFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_LifeInsuranceCorporateOrBankOwnedBorrowedAmounts" abstract="false" name="LifeInsuranceCorporateOrBankOwnedBorrowedAmounts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_LifeInsuranceCorporateOrBankOwnedInterestRate" abstract="false" name="LifeInsuranceCorporateOrBankOwnedInterestRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="spxc_LifeInsurancePolicyMaximumBorrowingCapacity" abstract="false" name="LifeInsurancePolicyMaximumBorrowingCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_InterestRateSwapFromDecember2024Member" abstract="true" name="InterestRateSwapFromDecember2024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <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_PerformanceSharesRestrictedStockandRestrictedStockUnitsMember" abstract="true" name="PerformanceSharesRestrictedStockandRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_NonEmployeeDirectorMember" abstract="true" name="NonEmployeeDirectorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_LargePowerProjectsMember" abstract="true" name="LargePowerProjectsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="spxc_PaymentsForBondsIssued" abstract="false" name="PaymentsForBondsIssued" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_SiteContingencyNumberOfSites" abstract="false" name="SiteContingencyNumberOfSites" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="spxc_SiteContingencyNumberOfSitesOnWhichEntityPotentiallyResponsible" abstract="false" name="SiteContingencyNumberOfSitesOnWhichEntityPotentiallyResponsible" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <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_UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccruedNet" abstract="false" name="UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccruedNet" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="spxc_EquitySecurityFVNIRollForward" abstract="true" name="EquitySecurityFVNIRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="spxc_NeptronicIncMember" abstract="true" name="NeptronicIncMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
