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  <xsd:element abstract="true" id="nnbr_IncomeTaxesTable" name="IncomeTaxesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_IncreaseDecreaseinAllocatedSharebasedCompensationExpenseDuetoChangeinVesting" name="IncreaseDecreaseinAllocatedSharebasedCompensationExpenseDuetoChangeinVesting" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_IncrementalTermLoanMember" name="IncrementalTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_InterestRateSwapDecember312020toDecember302021Member" name="InterestRateSwapDecember312020toDecember302021Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_InterestRateSwapDecember312021toOctober192022Member" name="InterestRateSwapDecember312021toOctober192022Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_InterestRateSwapFebruary122019toDecember302020Member" name="InterestRateSwapFebruary122019toDecember302020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_LeaseLiability" name="LeaseLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="nnbr_LeaseRightOfUseAsset" name="LeaseRightOfUseAsset" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nnbr_LeasesWeightedAverageDiscountRateAbstract" name="LeasesWeightedAverageDiscountRateAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_LesseeOperatingLeaseLeaseNotYetCommencedAmount" name="LesseeOperatingLeaseLeaseNotYetCommencedAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nnbr_LifeSciencesMember" name="LifeSciencesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_MajorCustomerMember" name="MajorCustomerMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_MaturityPeriodOfHighlyLiquidInvestments" name="MaturityPeriodOfHighlyLiquidInvestments" nillable="true" substitutionGroup="xbrli:item" type="us-types:durationStringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_MobileSolutionsMember" name="MobileSolutionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_NetIncomeLossPerCommonSharePolicyTextBlock" name="NetIncomeLossPerCommonSharePolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_NetIncomePerShareLineItems" name="NetIncomePerShareLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_NetIncomePerShareTable" name="NetIncomePerShareTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_NonExecutiveDirectorsMember" name="NonExecutiveDirectorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_NumberOfManufacturingFacilities" name="NumberOfManufacturingFacilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_OperatingLossCarryforwardsExpirationBeginningYear" name="OperatingLossCarryforwardsExpirationBeginningYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:gYearItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_OtherAcquisitionsMember" name="OtherAcquisitionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIDiscontinuedOperationsafterTax" name="OtherComprehensiveIncomeLossReclassificationAdjustmentfromAOCIDiscontinuedOperationsafterTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_OtherCountryMember" name="OtherCountryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_PBCBusinessMember" name="PBCBusinessMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_ParagonMedicalIncMember" name="ParagonMedicalIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PayPeriodForAccruedRestructuringAndIntegrationCosts" name="PayPeriodForAccruedRestructuringAndIntegrationCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PaymentsofDebtIssuanceCostsandPrepaymentCosts" name="PaymentsofDebtIssuanceCostsandPrepaymentCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PaymentstoAcquirePropertyPlantandEquipmentContinuingOperations" name="PaymentstoAcquirePropertyPlantandEquipmentContinuingOperations" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_PerformanceSharesReturnOnInvestedCapitalMember" name="PerformanceSharesReturnOnInvestedCapitalMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_PerformanceSharesTsrAwardsMember" name="PerformanceSharesTsrAwardsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_PowerSolutionsMember" name="PowerSolutionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_PrecisionBearingComponentsSegmentMember" name="PrecisionBearingComponentsSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PreferredStockConversionLimitPercent" name="PreferredStockConversionLimitPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PreferredStockConversionPercentageOfVolumeWeightedAverageMarketPricePercent" name="PreferredStockConversionPercentageOfVolumeWeightedAverageMarketPricePercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PreferredStockPeriodofVolumeWeightedAveragePricePerCommonShare" name="PreferredStockPeriodofVolumeWeightedAveragePricePerCommonShare" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_PrinciplesOfConsolidationPolicyTextBlock" name="PrinciplesOfConsolidationPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" name="PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_RegulatoryAssetsAbstract" name="RegulatoryAssetsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_RestructuringAndIntegrationCharges" name="RestructuringAndIntegrationCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="nnbr_RestructuringChargesInOtherCurrentAndNoncurrentLiabilities" name="RestructuringChargesInOtherCurrentAndNoncurrentLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_ScheduleOfDeferredTaxAssetsValuationAllowanceTable" name="ScheduleOfDeferredTaxAssetsValuationAllowanceTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ScheduleOfPerformanceUnitAwardsBasedOnExpectedPerformanceTableTextBlock" name="ScheduleOfPerformanceUnitAwardsBasedOnExpectedPerformanceTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SecondLienCreditAgreementMember" name="SecondLienCreditAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SeniorSecuredRevolvingFacilityMember" name="SeniorSecuredRevolvingFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SeniorSecuredTermLoanBMember" name="SeniorSecuredTermLoanBMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardBasedOnThresholdPerformanceAchievementPercentage" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardBasedOnThresholdPerformanceAchievementPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeitureRate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeitureRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAvailable" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAvailable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesIssuableBasedOnThresholdPerformance" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesIssuableBasedOnThresholdPerformance" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfAward" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfAward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnMaximumPerformanceAchievementPercentage" name="ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnMaximumPerformanceAchievementPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnTargetPerformanceAchievementPercentage" name="ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnTargetPerformanceAchievementPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnMaximumPerformance" name="ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnMaximumPerformance" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnTargetPerformance" name="ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnTargetPerformance" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceAndAdditionalDisclosuresAbstract" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceAndAdditionalDisclosuresAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_SharesPaidForTaxWithholdingAndForfeitedForShareBasedCompensation" name="SharesPaidForTaxWithholdingAndForfeitedForShareBasedCompensation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_SouthernCaliforniaTechnicalArtsInc.Member" name="SouthernCaliforniaTechnicalArtsInc.Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_StateNetOperatingLossCarryforwardsMember" name="StateNetOperatingLossCarryforwardsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_TemporaryEquityAllocationOfIssuanceCosts" name="TemporaryEquityAllocationOfIssuanceCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="nnbr_TemporaryEquityDividendRatePercentage" name="TemporaryEquityDividendRatePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_TemporaryEquityFairValueOfWarrantsIssued" name="TemporaryEquityFairValueOfWarrantsIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="nnbr_TemporaryEquityIncreaseinDividendRatePercentage" name="TemporaryEquityIncreaseinDividendRatePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="nnbr_TemporaryEquityRecognitionOfBifurcatedEmbeddedDerivative" name="TemporaryEquityRecognitionOfBifurcatedEmbeddedDerivative" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="nnbr_ValuationAllowanceDeferredTaxAssetChangeInAmountIncrease" name="ValuationAllowanceDeferredTaxAssetChangeInAmountIncrease" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_WeightedAverageRemainingLeaseTermAbstract" name="WeightedAverageRemainingLeaseTermAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nnbr_WuxiWeifuAutocamPrecisionMachineryCompanyLtdMember" name="WuxiWeifuAutocamPrecisionMachineryCompanyLtdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
