<SEC-DOCUMENT>0000886346-15-000075.txt : 20150312
<SEC-HEADER>0000886346-15-000075.hdr.sgml : 20150312
<ACCEPTANCE-DATETIME>20150312151909
ACCESSION NUMBER:		0000886346-15-000075
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20150310
FILED AS OF DATE:		20150312
DATE AS OF CHANGE:		20150312

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			KADANT INC
		CENTRAL INDEX KEY:			0000886346
		STANDARD INDUSTRIAL CLASSIFICATION:	SPECIAL INDUSTRY MACHINERY (NO METALWORKING MACHINERY) [3550]
		IRS NUMBER:				521762325
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0103

	BUSINESS ADDRESS:	
		STREET 1:		ONE TECHNOLOGY PARK DRIVE
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886
		BUSINESS PHONE:		(978) 776-2000

	MAIL ADDRESS:	
		STREET 1:		ONE TECHNOLOGY PARK DRIVE
		CITY:			WESTFORD
		STATE:			MA
		ZIP:			01886

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	THERMO FIBERTEK INC
		DATE OF NAME CHANGE:	19930328

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			LAMBERT SANDRA L
		CENTRAL INDEX KEY:			0001247563

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11406
		FILM NUMBER:		15695719

	MAIL ADDRESS:	
		STREET 1:		ONE ACTO PLACE
		STREET 2:		SUITE 202
		CITY:			ACTON
		STATE:			MA
		ZIP:			01720
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_142618793984018.xml
<DESCRIPTION>FORM 4
<TEXT>
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        <issuerName>KADANT INC</issuerName>
        <issuerTradingSymbol>KAI</issuerTradingSymbol>
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            <rptOwnerStreet2>ONE TECHNOLOGY PARK DRIVE</rptOwnerStreet2>
            <rptOwnerCity>WESTFORD</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01886</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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        <reportingOwnerRelationship>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, GENERAL COUNSEL, SECRETARY</officerTitle>
            <otherText></otherText>
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            </expirationDate>
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                <transactionCode>M</transactionCode>
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                <transactionShares>
                    <value>948</value>
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                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                    <value>D</value>
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        <derivativeTransaction>
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            </transactionDate>
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                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
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                <transactionShares>
                    <value>235</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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                <value>2017-03-10</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
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                <underlyingSecurityShares>
                    <value>235.0</value>
                    <footnoteId id="F4"/>
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            </underlyingSecurity>
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                <sharesOwnedFollowingTransaction>
                    <value>472</value>
                </sharesOwnedFollowingTransaction>
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    <footnotes>
        <footnote id="F1">The shares represent the partial settlement under a performance-based RSU award granted 3/7/2012. One-third of the RSU vested on 3/10/2015 and was converted to vested common stock on a one-for-one basis on the vesting date.</footnote>
        <footnote id="F2">The shares represent the partial settlement under a performance-based RSU award granted 3/6/2013. One-third of the RSU vested on 3/10/2015 and was converted to vested common stock on a one-for-one basis on the vesting date.</footnote>
        <footnote id="F3">The shares represent the partial settlement under a performance-based RSU award granted 3/5/2014.  One-third of the RSU vested on 3/10/2015 and was converted to vested common stock on a one-for-one basis on the vesting date.</footnote>
        <footnote id="F4">The shares represent the partial settlement under a time-based RSU award granted 3/5/2014. One-third vested on a one-for-one basis on the vesting date.</footnote>
        <footnote id="F5">The transactions reported on this Form 4 were executed pursuant to a Rule 10-b-5-1 trading plan adopted December 19, 2014.</footnote>
        <footnote id="F6">Represents the weighted average sale price.  The actual sales prices range from $46.29 to $46.51 per share.  The reporting person will supply the SEC, the Issuer, or a security holder of the Issuer, with full information regarding the number of shares at each price upon request.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Sandra L. Lambert</signatureName>
        <signatureDate>2015-03-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
