ASTM_F_2936_-_12.pdf

Designation:F293612An American National StandardStandard Specification forChocks,Ship Mooring,Cast Steel1This standard is issued under the fixed designation F2936;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers the principal dimensions andmaterials of closed chocks for installation on ships used formooring.1.2 Chocks can be used with either wire rope or fiber andsynthetic ropes.1.3 Chocks are for mounting directly on a deck,seat(foundation),or for mounting in a bulwark.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.2.Referenced Documents2.1 ASTM Standards:2A27/A27M Specification for Steel Castings,Carbon,forGeneral Application2.2 ANSI Standard:B 46.1 Surface Texture33.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 bulwarka structural enclosure along the edge of theship to serve as a rail.3.1.2 closed chocka metal flared ring-like fitting mountedon a ship,through which mooring lines pass to moor a ship.3.1.3 mooring ring or pipea chock mounted in the bul-wark and conforming to Type II and IV.3.1.4 rope contact areathat part of the fitting in contactwith the mooring line in normal mooring operations.4.Classification4.1 The size of the chocks will be identified by the nominalsize“L”and“H”of the opening as shown in Table 1 and Table2.4.2 Chocks are furnished in types as follows:4.2.1 Type IDeck mounted as shown in Fig.1 andconforming to all dimensions in Table 1.4.2.2 Type IIBulwark mounted as shown in Fig.2 andconforming to all dimensions in Table 2.4.2.3 Type IIIDeck mounted,conforming only to dimen-sions“L”and“H”of Table 1 and is of adequate strength to atleast meet 7.2 requirement and the requirements of Sections 6to 10.4.2.4 Type IVBulwark mounted,conforming only to di-mensions“L”and“H”of Table 2 and is of adequate strengthto at least meet 7.2 requirement and the requirements ofSections 6 to 10.4.3 Chocks shall be furnished in either of the followinggrades:4.3.1 Grade 1Surface finish shall be in the as castcondition.4.3.2 Grade 2Surface finish in way of rope contact shallbe in accordance with 8.2.5.Ordering Information5.1 Orders for chocks under this specification shall includethis standard,date,and the following:5.1.1 Descriptive information(size,material,etc.)of moor-ing lines,5.1.2 Quantity(number)of chocks required,5.1.3 Size(opening,L H),5.1.4 Type and grade,5.1.5 Primer and coating,if any(see 8.3),and5.1.6 Marking.6.Materials and Manufacture6.1 Material shall be cast steel in accordance with Specifi-cation A27/A27M,Grade 60-30.6.2 For Types III and IV the manufacturer shall certify thatstrength of the chock will at least meet 7.2 requirement,andthat it is suitable for the mooring lines specified in the orderinginformation.6.3 Casting shall be smooth,fine grain,and free of cracks,hot tears,and blow holes,detrimental to end use.Defectshaving an area larger than 25 by 25 mm2and a depth of morethan 10%of the thickness in way thereof will be cause forrejection.Smaller defects in way of rope contact shall be1This specification is under the jurisdiction of ASTM Committee F25 on Shipsand Marine Technology and is the direct responsibility of Subcommittee F25.01 onStructures.Current edition approved Jan.1,2012.Published February 2012.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 welded and finished smooth.Where applicable,welding shallbe in accordance with code requirements,such as ABS,AWS,and so on,and may require post weld heat treatment(PWHT).6.4 All excess material,vents,and gates shall be removedand finished smooth to match the surrounding surface.6.5 Limber or drain holes shall be 25 mm in diameter andprovided in webs and brackets to prevent water entrapment.6.6 Type I shall be in accordance with Fig.1 and Table 1.6.7 Type II shall be in accordance with Fig.2 and Table 2.7.Strength Requirements7.1 The closed chocks are to be designed to withstand thehorizontal and vertical load cases.Horizontal and verticalloadings were considered individually;both loadings were notconsidered simultaneously.7.1.1 Case 1Horizontal loading(see Fig.3).7.1.2 Case 2Vertical loading(see Figs.4-6).7.2 The combined stress is limited to 85%of the yieldstress of the material.8.Workmanship,Finish,and Appearance8.1 Casting shall be sand,grit,or shot