| | | | | | | | | | | | | | | | | | | | | |
<?xml version="1.0" encoding="windows-1252"?> |
<!-- XBRL document created by Certent Disclosure Management 6.36.2.2 --> |
<!-- Based on XBRL 2.1 --> |
<!-- Created on: 3/10/2020 4:08:54 PM --> |
<!-- Modified on: 3/10/2020 4:08:54 PM --> |
<schema xmlns="http://www.w3.org/2001/XMLSchema" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" targetNamespace="http://www.gopresto.com/20191231" elementFormDefault="qualified" attributeFormDefault="unqualified" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:npk="http://www.gopresto.com/20191231" xmlns:us-types="http://fasb.org/us-types/2018-01-31"> |
| <annotation> |
| | <appinfo> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/StatementConsolidatedBalanceSheets" id="StatementConsolidatedBalanceSheets"> |
| <link:definition> 00100 - Statement - Consolidated Balance Sheets </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/StatementConsolidatedStatementsOfComprehensiveIncome" id="StatementConsolidatedStatementsOfComprehensiveIncome"> |
| <link:definition> 00200 - Statement - Consolidated Statements Of Comprehensive Income </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/StatementConsolidatedStatementsOfCashFlows" id="StatementConsolidatedStatementsOfCashFlows"> |
| <link:definition> 00300 - Statement - Consolidated Statements Of Cash Flows </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfAmortizedCostsAndFairValuesOfMarketableSecuritiesDetails" id="DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfAmortizedCostsAndFairValuesOfMarketableSecuritiesDetails"> |
| <link:definition> 40103 - Disclosure - Summary Of Significant Accounting Policies (Summary Of The Amortized Costs And Fair Values Of Marketable Securities) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxesScheduleOfProvisionForIncomeTaxesDetails" id="DisclosureIncomeTaxesScheduleOfProvisionForIncomeTaxesDetails"> |
| <link:definition> 40802 - Disclosure - Income Taxes (Schedule Of Provision For Income Taxes) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxesReconciliationOfStatutoryRateToEffectiveRateDetails" id="DisclosureIncomeTaxesReconciliationOfStatutoryRateToEffectiveRateDetails"> |
| <link:definition> 40803 - Disclosure - Income Taxes (Reconciliation Of Statutory Rate to Effective Rate) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails" id="DisclosureIncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails"> |
| <link:definition> 40804 - Disclosure - Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureEnvironmentalScheduleOfExpectedFuturePaymentsOfEnvironmentalMattersDetails" id="DisclosureEnvironmentalScheduleOfExpectedFuturePaymentsOfEnvironmentalMattersDetails"> |
| <link:definition> 41102 - Disclosure - Environmental (Schedule Of Expected Future Payments Of Environmental Matters) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeasesSummaryOfLeaseCostDetails" id="DisclosureLeasesSummaryOfLeaseCostDetails"> |
| <link:definition> 41302 - Disclosure - Leases (Summary of Lease Cost) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeasesSummaryOfMaturitiesOfLeaseLiabilitiesAlternateDetails" id="DisclosureLeasesSummaryOfMaturitiesOfLeaseLiabilitiesAlternateDetails"> |
| <link:definition> 41303 - Disclosure - Leases (Summary of Maturities of Lease Liabilities Alternate) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeasesSummaryOfOperatingLeaseLiabilityMaturitiesDetails" id="DisclosureLeasesSummaryOfOperatingLeaseLiabilityMaturitiesDetails"> |
| <link:definition> 41303 - Disclosure - Leases (Summary of Operating Lease Liability Maturities) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeasesSummaryOfLeaseIncomeFromOperatingLeasePaymentsDetails" id="DisclosureLeasesSummaryOfLeaseIncomeFromOperatingLeasePaymentsDetails"> |
| <link:definition> 41304 - Disclosure - Leases (Summary of Lease Income from Operating Lease Payments) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDiscontinuedOperationsSummaryOfDiscontinuedOperationsDetails" id="DisclosureDiscontinuedOperationsSummaryOfDiscontinuedOperationsDetails"> |
| <link:definition> 41602 - Disclosure - Discontinued Operations (Summary Of Discontinued Operations) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDiscontinuedOperationsSummaryOfMajorClassesOfAssetsAndLiabilitiesDetails" id="DisclosureDiscontinuedOperationsSummaryOfMajorClassesOfAssetsAndLiabilitiesDetails"> |
| <link:definition> 41603 - Disclosure - Discontinued Operations (Summary of Major Classes of Assets and Liabilities) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessAcquisitionScheduleOfAssetsAcquiredAndLiabilitiesAssumedDetails" id="DisclosureBusinessAcquisitionScheduleOfAssetsAcquiredAndLiabilitiesAssumedDetails"> |
| <link:definition> 41802 - Disclosure - Business Acquisition (Schedule of Assets Acquired and Liabilities Assumed) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DocumentDocumentAndEntityInformation" id="DocumentDocumentAndEntityInformation"> |
| <link:definition> 00090 - Document - Document And Entity Information </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/StatementConsolidatedBalanceSheetsParenthetical" id="StatementConsolidatedBalanceSheetsParenthetical"> |
| <link:definition> 00105 - Statement - Consolidated Balance Sheets (Parenthetical) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/StatementConsolidatedStatementsOfStockholdersEquity" id="StatementConsolidatedStatementsOfStockholdersEquity"> |
| <link:definition> 00400 - Statement - Consolidated Statements Of Stockholders' Equity </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/StatementConsolidatedStatementsOfStockholdersEquityParenthetical" id="StatementConsolidatedStatementsOfStockholdersEquityParenthetical"> |
| <link:definition> 00405 - Statement - Consolidated Statements Of Stockholders' Equity (Parenthetical) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPolicies" id="DisclosureSummaryOfSignificantAccountingPolicies"> |
| <link:definition> 10101 - Disclosure - Summary Of Significant Accounting Policies </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInventories" id="DisclosureInventories"> |
| <link:definition> 10201 - Disclosure - Inventories </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureAccruedLiabilities" id="DisclosureAccruedLiabilities"> |
| <link:definition> 10301 - Disclosure - Accrued Liabilities </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureTreasuryStock" id="DisclosureTreasuryStock"> |
| <link:definition> 10401 - Disclosure - Treasury Stock </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureNetEarningsPerShare" id="DisclosureNetEarningsPerShare"> |
| <link:definition> 10501 - Disclosure - Net Earnings Per Share </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureStockBasedCompensation" id="DisclosureStockBasedCompensation"> |
| <link:definition> 10601 - Disclosure - Stock-Based Compensation </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/Disclosure401KPlan" id="Disclosure401KPlan"> |
| <link:definition> 10701 - Disclosure - 401(k) Plan </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxes" id="DisclosureIncomeTaxes"> |
| <link:definition> 10801 - Disclosure - Income Taxes </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureCommitmentsAndContingencies" id="DisclosureCommitmentsAndContingencies"> |
| <link:definition> 10901 - Disclosure - Commitments And Contingencies </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureConcentrations" id="DisclosureConcentrations"> |
| <link:definition> 11001 - Disclosure - Concentrations </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureEnvironmental" id="DisclosureEnvironmental"> |
| <link:definition> 11101 - Disclosure - Environmental </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessSegments" id="DisclosureBusinessSegments"> |
| <link:definition> 11201 - Disclosure - Business Segments </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeases" id="DisclosureLeases"> |
| <link:definition> 11301 - Disclosure - Leases </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInterimFinancialInformation" id="DisclosureInterimFinancialInformation"> |
| <link:definition> 11401 - Disclosure - Interim Financial Information </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLineOfCreditAndCommercialLettersOfCredit" id="DisclosureLineOfCreditAndCommercialLettersOfCredit"> |
| <link:definition> 11501 - Disclosure - Line Of Credit And Commercial Letters Of Credit </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDiscontinuedOperations" id="DisclosureDiscontinuedOperations"> |
| <link:definition> 11601 - Disclosure - Discontinued Operations </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDivestiture" id="DisclosureDivestiture"> |
| <link:definition> 11701 - Disclosure - Divestiture </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessAcquisition" id="DisclosureBusinessAcquisition"> |
| <link:definition> 11801 - Disclosure - Business Acquisition </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureOther" id="DisclosureOther"> |
| <link:definition> 11901 - Disclosure - Other </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSubsequentEvent" id="DisclosureSubsequentEvent"> |
| <link:definition> 12001 - Disclosure - Subsequent Event </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/ScheduleValuationAndQualifyingAccounts" id="ScheduleValuationAndQualifyingAccounts"> |
| <link:definition> 12101 - Schedule - Valuation And Qualifying Accounts </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicy" id="DisclosureSummaryOfSignificantAccountingPoliciesPolicy"> |
| <link:definition> 20102 - Disclosure - Summary Of Significant Accounting Policies (Policy) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPoliciesTables" id="DisclosureSummaryOfSignificantAccountingPoliciesTables"> |
| <link:definition> 30103 - Disclosure - Summary Of Significant Accounting Policies (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInventoriesTables" id="DisclosureInventoriesTables"> |
| <link:definition> 30203 - Disclosure - Inventories (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureStockBasedCompensationTables" id="DisclosureStockBasedCompensationTables"> |
| <link:definition> 30603 - Disclosure - Stock-Based Compensation (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxesTables" id="DisclosureIncomeTaxesTables"> |
| <link:definition> 30803 - Disclosure - Income Taxes (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureEnvironmentalTables" id="DisclosureEnvironmentalTables"> |
| <link:definition> 31103 - Disclosure - Environmental (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessSegmentsTables" id="DisclosureBusinessSegmentsTables"> |
| <link:definition> 31203 - Disclosure - Business Segments (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeasesTables" id="DisclosureLeasesTables"> |
| <link:definition> 31303 - Disclosure - Leases (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInterimFinancialInformationTables" id="DisclosureInterimFinancialInformationTables"> |
| <link:definition> 31403 - Disclosure - Interim Financial Information (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDiscontinuedOperationsTables" id="DisclosureDiscontinuedOperationsTables"> |
| <link:definition> 31603 - Disclosure - Discontinued Operations (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessAcquisitionTables" id="DisclosureBusinessAcquisitionTables"> |
| <link:definition> 31803 - Disclosure - Business Acquisition (Tables) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPoliciesNarrativeDetails" id="DisclosureSummaryOfSignificantAccountingPoliciesNarrativeDetails"> |
| <link:definition> 40101 - Disclosure - Summary Of Significant Accounting Policies (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPoliciesTimingOfPerformanceObligationNarrativeDetails" id="DisclosureSummaryOfSignificantAccountingPoliciesTimingOfPerformanceObligationNarrativeDetails"> |
| <link:definition> 40102 - Disclosure - Summary Of Significant Accounting Policies (Timing Of Performance Obligation) (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfChangesInProductWarrantyLiabilityDetails" id="DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfChangesInProductWarrantyLiabilityDetails"> |
| <link:definition> 40104 - Disclosure - Summary Of Significant Accounting Policies (Schedule Of Changes In Product Warranty Liability) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInventoriesNarrativeDetails" id="DisclosureInventoriesNarrativeDetails"> |
| <link:definition> 40201 - Disclosure - Inventories (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInventoriesScheduleOfPotentialImpactOfLifoValuationToFifoValuationDetails" id="DisclosureInventoriesScheduleOfPotentialImpactOfLifoValuationToFifoValuationDetails"> |
| <link:definition> 40202 - Disclosure - Inventories (Schedule Of Potential Impact Of LIFO Valuation to FIFO Valuation) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureAccruedLiabilitiesNarrativeDetails" id="DisclosureAccruedLiabilitiesNarrativeDetails"> |
| <link:definition> 40301 - Disclosure - Accrued Liabilities (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureTreasuryStockNarrativeDetails" id="DisclosureTreasuryStockNarrativeDetails"> |
| <link:definition> 40401 - Disclosure - Treasury Stock (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureStockBasedCompensationNarrativeDetails" id="DisclosureStockBasedCompensationNarrativeDetails"> |
| <link:definition> 40601 - Disclosure - Stock-Based Compensation (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureStockBasedCompensationScheduleOfActivityForNonVestedRestrictedStockDetails" id="DisclosureStockBasedCompensationScheduleOfActivityForNonVestedRestrictedStockDetails"> |
| <link:definition> 40602 - Disclosure - Stock-Based Compensation (Schedule Of Activity For Non-Vested Restricted Stock) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/Disclosure401KPlanNarrativeDetails" id="Disclosure401KPlanNarrativeDetails"> |
| <link:definition> 40701 - Disclosure - 401(k) Plan (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxesNarrativeDetails" id="DisclosureIncomeTaxesNarrativeDetails"> |
| <link:definition> 40801 - Disclosure - Income Taxes (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureIncomeTaxesReconciliationOfUnrecognizedTaxBenefitsDetails" id="DisclosureIncomeTaxesReconciliationOfUnrecognizedTaxBenefitsDetails"> |
| <link:definition> 40805 - Disclosure - Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureConcentrationsNarrativeDetails" id="DisclosureConcentrationsNarrativeDetails"> |
| <link:definition> 41001 - Disclosure - Concentrations (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureEnvironmentalNarrativeDetails" id="DisclosureEnvironmentalNarrativeDetails"> |
| <link:definition> 41101 - Disclosure - Environmental (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessSegmentsNarrativeDetails" id="DisclosureBusinessSegmentsNarrativeDetails"> |
| <link:definition> 41201 - Disclosure - Business Segments (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessSegmentsSummaryOfBusinessSegmentInformationDetails" id="DisclosureBusinessSegmentsSummaryOfBusinessSegmentInformationDetails"> |
| <link:definition> 41201 - Disclosure - Business Segments (Summary Of Business Segment Information) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLeasesNarrativeDetails" id="DisclosureLeasesNarrativeDetails"> |
| <link:definition> 41301 - Disclosure - Leases (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureInterimFinancialInformationScheduleOfQuarterlyFinancialInformationDetails" id="DisclosureInterimFinancialInformationScheduleOfQuarterlyFinancialInformationDetails"> |
| <link:definition> 41401 - Disclosure - Interim Financial Information (Schedule Of Quarterly Financial Information) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureLineOfCreditAndCommercialLettersOfCreditNarrativeDetails" id="DisclosureLineOfCreditAndCommercialLettersOfCreditNarrativeDetails"> |
| <link:definition> 41501 - Disclosure - Line Of Credit And Commercial Letters Of Credit (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDiscontinuedOperationsNarrativeDetails" id="DisclosureDiscontinuedOperationsNarrativeDetails"> |
| <link:definition> 41601 - Disclosure - Discontinued Operations (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureDivestitureNarrativeDetails" id="DisclosureDivestitureNarrativeDetails"> |
| <link:definition> 41701 - Disclosure - Divestiture (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessAcquisitionNarrativeDetails" id="DisclosureBusinessAcquisitionNarrativeDetails"> |
| <link:definition> 41801 - Disclosure - Business Acquisition (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureBusinessAcquisitionScheduleOfProFormaResultsOfOperationsDetails" id="DisclosureBusinessAcquisitionScheduleOfProFormaResultsOfOperationsDetails"> |
| <link:definition> 41803 - Disclosure - Business Acquisition (Schedule of Pro Forma Results of Operations) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureOtherNarrativeDetails" id="DisclosureOtherNarrativeDetails"> |
| <link:definition> 41901 - Disclosure - Other (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/DisclosureSubsequentEventNarrativeDetails" id="DisclosureSubsequentEventNarrativeDetails"> |
| <link:definition> 42001 - Disclosure - Subsequent Event (Narrative) (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:roleType roleURI="http://www.gopresto.com/2010-09-30/role/ScheduleValuationAndQualifyingAccountsDetails" id="ScheduleValuationAndQualifyingAccountsDetails"> |
| <link:definition> 42101 - Schedule - Valuation And Qualifying Accounts (Details) </link:definition> |
| <link:usedOn> link:presentationLink </link:usedOn> |
| <link:usedOn> link:calculationLink </link:usedOn> |
| <link:usedOn> link:definitionLink </link:usedOn> |
| </link:roleType> |
| | | <link:linkbaseRef xlink:type="simple" xlink:href="npk-20191231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Presentation Links, all"/> |
| | | <link:linkbaseRef xlink:type="simple" xlink:href="npk-20191231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Label Links, all"/> |
| | | <link:linkbaseRef xlink:type="simple" xlink:href="npk-20191231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Calculation Links, all"/> |
| | | <link:linkbaseRef xlink:type="simple" xlink:href="npk-20191231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Definition Links, all"/> |
| | | </appinfo> |
| | </annotation> |
| <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/> |
| <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd"/> |
| <import namespace="http://xbrl.sec.gov/dei/2018-01-31" schemaLocation="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd"/> |
| <import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd"/> |
| <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd"/> |
| <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd"/> |
| <import namespace="http://fasb.org/us-roles/2018-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2018/elts/us-roles-2018-01-31.xsd"/> |
| <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/> |
| <import namespace="http://fasb.org/us-gaap/2018-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd"/> |
| <import namespace="http://fasb.org/srt/2018-01-31" schemaLocation="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd"/> |
| <element id="npk_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration"/> |
| <element id="npk_HousewaresSmallAppliancesMember" name="HousewaresSmallAppliancesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_DefenseProductsMember" name="DefenseProductsMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_CashCashEquivalentsAndMarketableSecuritiesPolicyTextBlock" name="CashCashEquivalentsAndMarketableSecuritiesPolicyTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_AccountsReceivableCollectionPeriod" name="AccountsReceivableCollectionPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_StandardProductWarrantyCoveragePeriod" name="StandardProductWarrantyCoveragePeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ConcentrationsAbstract" name="ConcentrationsAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration"/> |
| <element id="npk_SupplyCommitmentCommitmentTerm" name="SupplyCommitmentCommitmentTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_GovernmentContractNumberOfContractors" name="GovernmentContractNumberOfContractors" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_MajorCustomersContributingToNetSales" name="MajorCustomersContributingToNetSales" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_NumberOfEntityEmpolyeesUnionMembers" name="NumberOfEntityEmpolyeesUnionMembers" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant"/> |
| <element id="npk_PercentageOfEntityEmployeesUnionMembers" name="PercentageOfEntityEmployeesUnionMembers" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant"/> |
| <element id="npk_DeferredTaxAssetsInsurance" name="DeferredTaxAssetsInsurance" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit"/> |
| <element id="npk_DeferredTaxAssetsEnvironmental" name="DeferredTaxAssetsEnvironmental" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit"/> |
| <element id="npk_DeferredTaxLiabilitiesDepreciation" name="DeferredTaxLiabilitiesDepreciation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit"/> |
| <element id="npk_PercentageOfSpecifiedSalaryAmountMatchedByEmployer" name="PercentageOfSpecifiedSalaryAmountMatchedByEmployer" nillable="true" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_EmployerContributionCommonStockMember" name="EmployerContributionCommonStockMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_EmployerContributionCashMember" name="EmployerContributionCashMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_DefinedBenefitPlanUnionEmployeesMember" name="DefinedBenefitPlanUnionEmployeesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ScheduleOfPotentialImpactOfLIFOValuationToFIFOValuationTableTextBlock" name="ScheduleOfPotentialImpactOfLIFOValuationToFIFOValuationTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_SignificantAccountingPoliciesTable" name="SignificantAccountingPoliciesTable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" xbrli:periodType="duration"/> |
| <element id="npk_SignificantAccountingPoliciesLineItems" name="SignificantAccountingPoliciesLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration"/> |
| <element id="npk_ShareBasedCompensationArrangementNumberOfPlanParticipants" name="ShareBasedCompensationArrangementNumberOfPlanParticipants" nillable="true" type="xbrli:positiveIntegerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_OtherAbstract" name="OtherAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration"/> |
| <element id="npk_OtherDisclosureTextBlock" name="OtherDisclosureTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_NumberOfDaysToTenderSecurites" name="NumberOfDaysToTenderSecurites" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingYear" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingYear" nillable="true" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_DefinedContributionPlanCertainEmployeesMember" name="DefinedContributionPlanCertainEmployeesMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_InventoryLifoReserveEffectOnEarningsPerShare" name="InventoryLifoReserveEffectOnEarningsPerShare" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ScheduleOfExpectedFuturePaymentsOfEnvironmentalMattersTableTextBlock" name="ScheduleOfExpectedFuturePaymentsOfEnvironmentalMattersTableTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_DeferredIncomeTaxExpenseBenefitIncludingUnrealizedGainOnAvailableForSaleSecurities" name="DeferredIncomeTaxExpenseBenefitIncludingUnrealizedGainOnAvailableForSaleSecurities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit"/> |
| <element id="npk_RegularDividendsPerSharePaid" name="RegularDividendsPerSharePaid" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ExtraDividendsPerSharePaid" name="ExtraDividendsPerSharePaid" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_BusinessAcquisitionProFormaEarningsPerShareBasicAndDiluted" name="BusinessAcquisitionProFormaEarningsPerShareBasicAndDiluted" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_NoncashRetirementPlanExpense" name="NoncashRetirementPlanExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit"/> |
| <element id="npk_ExpectedPrepaymentUtilizationPeriod" name="ExpectedPrepaymentUtilizationPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_OtherAssetsPolicy" name="OtherAssetsPolicy" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_GainOnInvoluntaryConversionOfMachineryAndEquipment" name="GainOnInvoluntaryConversionOfMachineryAndEquipment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit"/> |
| <element id="npk_LessorOperatingLeaseOptionToTerminateTerm" name="LessorOperatingLeaseOptionToTerminateTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_HoldingPeriodFollowingRecognitionOfRevenue" name="HoldingPeriodFollowingRecognitionOfRevenue" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_OriginalLeaseAgreementMember" name="OriginalLeaseAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_AmendedLeaseAgreementMember" name="AmendedLeaseAgreementMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_CurrentTwelveMonthEstimateMember" name="CurrentTwelveMonthEstimateMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_DivestitureAbstract" name="DivestitureAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration"/> |
| <element id="npk_DivestitureTextBlock" name="DivestitureTextBlock" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ThirdPartyMember" name="ThirdPartyMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_Leases" name="Leases" nillable="true" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ShortTermAndVariableLeaseCost" name="ShortTermAndVariableLeaseCost" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit"/> |
| <element id="npk_OneeventTechnologiesInc.Member" name="OneeventTechnologiesInc.Member" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_SafetyMember" name="SafetyMember" nillable="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ProceedsFromLegalSettlementsInvestingActivities" name="ProceedsFromLegalSettlementsInvestingActivities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit"/> |
| <element id="npk_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseLeaseAssets" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseLeaseAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit"/> |
| <element id="npk_BusinessCombinationEarnOutEvaluationPeriod" name="BusinessCombinationEarnOutEvaluationPeriod" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_RegularDividendsPerShareDeclared" name="RegularDividendsPerShareDeclared" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_ExtraDividendsPerShareDeclared" name="ExtraDividendsPerShareDeclared" nillable="true" type="num:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| <element id="npk_RevenueFromContractWithCustomerContractTerm" name="RevenueFromContractWithCustomerContractTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration"/> |
| </schema> |