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  <element name="ForeignTaxCreditCarryForwardValuationAllowance" id="nnbr_ForeignTaxCreditCarryForwardValuationAllowance" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ForeignTaxCreditToBeUtilized" id="nnbr_ForeignTaxCreditToBeUtilized" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxesLineItems" id="nnbr_IncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxesTable" id="nnbr_IncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationLineItems" id="nnbr_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationTable" id="nnbr_IncomeTaxExpenseBenefitContinuingOperationsIncomeTaxReconciliationTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="IncomeTaxRateReconciliationForeignTaxCreditExpirationAmount" id="nnbr_IncomeTaxRateReconciliationForeignTaxCreditExpirationAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxReconciliationCapitalGainOnReturnOfBasis" id="nnbr_IncomeTaxReconciliationCapitalGainOnReturnOfBasis" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxReconciliationPermanentDifferencesOther" id="nnbr_IncomeTaxReconciliationPermanentDifferencesOther" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="KeyEmployeesMember" id="nnbr_KeyEmployeesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="KilkennyPlantMember" id="nnbr_KilkennyPlantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LandUnderCapitalLeaseMember" id="nnbr_LandUnderCapitalLeaseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LeaseAgreementPeriod" id="nnbr_LeaseAgreementPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityBasisSpreadOnVariableRatePostAmendment" id="nnbr_LineOfCreditFacilityBasisSpreadOnVariableRatePostAmendment" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditFacilityBasisSpreadOnVariableRatePreAmendment" id="nnbr_LineOfCreditFacilityBasisSpreadOnVariableRatePreAmendment" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LineOfCreditLiborRate" id="nnbr_LineOfCreditLiborRate" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtPercentageBearingFixedInterestRatePostAmendment" id="nnbr_LongTermDebtPercentageBearingFixedInterestRatePostAmendment" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LongTermDebtPercentageBearingFixedInterestRatePreAmendment" id="nnbr_LongTermDebtPercentageBearingFixedInterestRatePreAmendment" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaturityPeriodOfHighlyLiquidInvestments" id="nnbr_MaturityPeriodOfHighlyLiquidInvestments" type="us-types:durationStringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaturityPeriodOneMember" id="nnbr_MaturityPeriodOneMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaturityPeriodThreeMember" id="nnbr_MaturityPeriodThreeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MaturityPeriodTwoMember" id="nnbr_MaturityPeriodTwoMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MetalBearingComponentsSegmentMember" id="nnbr_MetalBearingComponentsSegmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MinimumAgeForIrsCatchUpProvisionLimit" id="nnbr_MinimumAgeForIrsCatchUpProvisionLimit" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetIncomeLossPerCommonSharePolicyTextBlock" id="nnbr_NetIncomeLossPerCommonSharePolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetOperatingLossesUtilizedToOffsetTaxExpense" id="nnbr_NetOperatingLossesUtilizedToOffsetTaxExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetReductionForeignInterestAndPenalties" id="nnbr_NetReductionForeignInterestAndPenalties" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonCashFinancingAndInvestingActivitiesShareBasedCompensation" id="nnbr_NonCashFinancingAndInvestingActivitiesShareBasedCompensation" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonEmployeeDirectorsMember" id="nnbr_NonEmployeeDirectorsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OctoberTwentySixthTwoThousandTwelveFixedRateDebtMember" id="nnbr_OctoberTwentySixthTwoThousandTwelveFixedRateDebtMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLossCarryforwardsExpirationPeriod" id="nnbr_OperatingLossCarryforwardsExpirationPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PlasticAndRubberComponentsSegmentMember" id="nnbr_PlasticAndRubberComponentsSegmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PostEmploymentBenefitPeriodOfServiceForAwardGrant" id="nnbr_PostEmploymentBenefitPeriodOfServiceForAwardGrant" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PostemploymentBenefitsTranslationAdjustment" id="nnbr_PostemploymentBenefitsTranslationAdjustment" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PotentialToExpandCreditFacilityUnderCreditAgreement" id="nnbr_PotentialToExpandCreditFacilityUnderCreditAgreement" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrecisionMetalComponentsSegmentMember" id="nnbr_PrecisionMetalComponentsSegmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrinciplesOfConsolidationPolicyTextBlock" id="nnbr_PrinciplesOfConsolidationPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestructuringAndNonOperatingExpensesNetOfTax" id="nnbr_RestructuringAndNonOperatingExpensesNetOfTax" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReversalOfDeferredTaxAssetsValuationAllowance" id="nnbr_ReversalOfDeferredTaxAssetsValuationAllowance" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfChangesToPostEmploymentBenefitsTableTextBlock" id="nnbr_ScheduleOfChangesToPostEmploymentBenefitsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfStockOptionActivityLineItems" id="nnbr_ScheduleOfStockOptionActivityLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfStockOptionActivityTable" id="nnbr_ScheduleOfStockOptionActivityTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SevenYearFixedRateNotesMember" id="nnbr_SevenYearFixedRateNotesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeveranceIndemnitiesAccrualRate" id="nnbr_SeveranceIndemnitiesAccrualRate" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeitureRate" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeitureRate" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAvailable" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumNumberOfSharesAvailable" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitureRate" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeitureRate" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAverageGrantDateFairValue" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerShareWeightedAverageGrantDateFairValue" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfAward" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardTermOfAward" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationAwardSharesIssuableUponExerciseOfEachStockAppreciationRight" id="nnbr_ShareBasedCompensationAwardSharesIssuableUponExerciseOfEachStockAppreciationRight" type="xbrli:decimalItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationAwardSharesIssuableUponExerciseOfEachStockOption" id="nnbr_ShareBasedCompensationAwardSharesIssuableUponExerciseOfEachStockOption" type="xbrli:decimalItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SkfMember" id="nnbr_SkfMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SnrMember" id="nnbr_SnrMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SwingLineLoan" id="nnbr_SwingLineLoan" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UndiscountedAnnualLeasePayments" id="nnbr_UndiscountedAnnualLeasePayments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="VariableRateLongTermDebtMember" id="nnbr_VariableRateLongTermDebtMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
