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  <element name="ExecutiveManagementMember" id="nnbr_ExecutiveManagementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ForeignNetOperatingLossCarryforwardsMember" id="nnbr_ForeignNetOperatingLossCarryforwardsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" 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="IncrementalTermLoanMember" id="nnbr_IncrementalTermLoanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IntangibleLiabilityDisclosureAbstract" id="nnbr_IntangibleLiabilityDisclosureAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InterestRateSwapCashSettlement" id="nnbr_InterestRateSwapCashSettlement" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InterestRateSwapContractValueOutstanding" id="nnbr_InterestRateSwapContractValueOutstanding" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InventoryReductionMember" id="nnbr_InventoryReductionMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="LiborPeriod" id="nnbr_LiborPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" 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="NetIncomeLossPerCommonSharePolicyTextBlock" id="nnbr_NetIncomeLossPerCommonSharePolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetIncomePerShareLineItems" id="nnbr_NetIncomePerShareLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NetIncomePerShareTable" id="nnbr_NetIncomePerShareTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="NNLifeSciencesVandaliaLLCMember" id="nnbr_NNLifeSciencesVandaliaLLCMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonExecutiveDirectorsMember" id="nnbr_NonExecutiveDirectorsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonrecurringCostOfGoodsSoldIncrease" id="nnbr_NonrecurringCostOfGoodsSoldIncrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfManufacturingFacilities" id="nnbr_NumberOfManufacturingFacilities" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfMembersAwarded" id="nnbr_NumberOfMembersAwarded" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLossCarryforwardsExpirationBeginningYear" id="nnbr_OperatingLossCarryforwardsExpirationBeginningYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OtherCountryMember" id="nnbr_OtherCountryMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceSharesReturnOnInvestedCapitalMember" id="nnbr_PerformanceSharesReturnOnInvestedCapitalMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PerformanceSharesTsrAwardsMember" id="nnbr_PerformanceSharesTsrAwardsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrecisionBearingComponentsSegmentMember" id="nnbr_PrecisionBearingComponentsSegmentMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrecisionEngineeredProductsHoldingIncMember" id="nnbr_PrecisionEngineeredProductsHoldingIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrecisionEngineeredProductsSegmentMember" id="nnbr_PrecisionEngineeredProductsSegmentMember" 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="PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" id="nnbr_PropertyPlantAndEquipmentCapitalizedInterestCostsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RegulatoryAssetsAbstract" id="nnbr_RegulatoryAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestructuringAndIntegrationCharges" id="nnbr_RestructuringAndIntegrationCharges" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestructuringChargesInOtherCurrentAndNoncurrentLiabilities" id="nnbr_RestructuringChargesInOtherCurrentAndNoncurrentLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfDeferredTaxAssetsValuationAllowanceTable" id="nnbr_ScheduleOfDeferredTaxAssetsValuationAllowanceTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfPerformanceUnitAwardsBasedOnExpectedPerformanceTableTextBlock" id="nnbr_ScheduleOfPerformanceUnitAwardsBasedOnExpectedPerformanceTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SelectedQuarterlyFinancialInformationLineItems" id="nnbr_SelectedQuarterlyFinancialInformationLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SelectedQuarterlyFinancialInformationTable" id="nnbr_SelectedQuarterlyFinancialInformationTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="SeniorNotesDueTwoThousandAndTwentyMember" id="nnbr_SeniorNotesDueTwoThousandAndTwentyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSecuredRevolvingFacilityMember" id="nnbr_SeniorSecuredRevolvingFacilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeniorSecuredTermLoanBMember" id="nnbr_SeniorSecuredTermLoanBMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnMaximumPerformanceAchievementPercentage" id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnMaximumPerformanceAchievementPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnTargetPerformanceAchievementPercentage" id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardBasedOnTargetPerformanceAchievementPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardBasedOnThresholdPerformanceAchievementPercentage" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardBasedOnThresholdPerformanceAchievementPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsChangeInVestingEstimateWeightedAverageGrantDateFairValue" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsChangeInVestingEstimateWeightedAverageGrantDateFairValue" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedChangeInVestingEstimate" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedChangeInVestingEstimate" type="xbrli:sharesItemType" 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="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceAndAdditionalDisclosuresAbstract" id="nnbr_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceAndAdditionalDisclosuresAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnMaximumPerformance" id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnMaximumPerformance" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnTargetPerformance" id="nnbr_ShareBasedCompensationArrangementBySharebasedPaymentAwardPercentageOfSharesIssuableBasedOnTargetPerformance" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesIssuableBasedOnThresholdPerformance" id="nnbr_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfSharesIssuableBasedOnThresholdPerformance" type="num:percentItemType" 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="SharesPaidForTaxWithholdingAndForfeitedForShareBasedCompensation" id="nnbr_SharesPaidForTaxWithholdingAndForfeitedForShareBasedCompensation" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesLineItems" id="nnbr_SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesTable" id="nnbr_SignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="StateNetOperatingLossCarryforwardsMember" id="nnbr_StateNetOperatingLossCarryforwardsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubsequentFairValueAdjustmentsMember" id="nnbr_SubsequentFairValueAdjustmentsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TaxCreditCarryforwardExpirationBeginningYear" id="nnbr_TaxCreditCarryforwardExpirationBeginningYear" type="xbrli:gYearItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TaxCutsAndJobsActOf2017ChangeInTaxRateIncomeTaxExpenseBenefit" id="nnbr_TaxCutsAndJobsActOf2017ChangeInTaxRateIncomeTaxExpenseBenefit" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TaxCutsAndJobsActOf2017TransitionTaxForAccumulatedForeignEarningsIncomeTaxExpense" id="nnbr_TaxCutsAndJobsActOf2017TransitionTaxForAccumulatedForeignEarningsIncomeTaxExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ValuationAllowanceDeferredTaxAssetChangeInAmountDecrease" id="nnbr_ValuationAllowanceDeferredTaxAssetChangeInAmountDecrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ValuationAllowanceDeferredTaxAssetChangeInAmountIncrease" id="nnbr_ValuationAllowanceDeferredTaxAssetChangeInAmountIncrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WheelingPlantMember" id="nnbr_WheelingPlantMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WuxiWeifuAutocamPrecisionMachineryCompanyLtdMember" id="nnbr_WuxiWeifuAutocamPrecisionMachineryCompanyLtdMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>
