ASME B107.21:1998 pdf download WRENGH, CROWFOOT ATAGHMENTS (INCHN SERES)
4 REQUIREMENTS
4.1 lllustrations
The iflustrations shown herein are descriptive andnot rcstrictivc,and arc not intended to preclude themanufacture of wrenches which are otherwisc in accord-ance with this Standard.
4.2 viariking
Each wrench shall be marked in a permanent mannerwitii thie nomninai wrench opening size and the manufac-turer’s name or trademmark of such known characterthat the source of manufacturer and country of originmay be readily determincd.
4.3 Materials
The materials used in the manufacturing of thewrenches shali be such as to produce wrenches conform-ing to the physical requirements hereinafter.
4.4 Hardness
The socket shall be hardened and tempered to ahardness not less than 38 HRC nor more than 54 HIRC
4.5 Test Loads
When tested as specified. wrenches shall withstandthe test ioads specified in the applicable tables withoutfailure or permanent deformation (set) which mightaffect durability or serviceability of the wrenches.
4.6 Wrench Openings
4.6.1 Wrench opening tolerance shal! be such as toinsure acceptance when gaged with gages conformingto ASME B!07.17M.
4.6.2 Internal drive end dimensions shall conformto ASME B!07.4M except as noted in para. 4.8.1Two sides of the internal drive square shall be parallelto the longitudinal axis of the socket wrench within+3 deg
4.7 Finish
4.7.1 Surface Finish. All surfaces shall be thoroughly clcaned, free from cracks and essentia!ly freefrom burrs, pits, nodules, and shall have a maximumroughness height value of !25win. Measurement shallbe made with a surface measuring instrument using an0.03 in. roughness width cutoff. Surface roughnessvalues shall be rated as the arithmetical average. Defini-tions and nomenclature used within can he found inASME R46.1.
4.7.1.i Forge Fiash. Forge fiash shail be com-pletely removed from the periphery of the drive endand the open box end and open end portions of thewrench. Any remaining forge fiash on any remainingsurfaces between the heads shall blend smoothly withadjacent surfaces. External sharp edges shall be brokento 0.016 in. radius minimum, and shall not projectmore than 0.016 in. from adjacent surfaccs.
4.7.2 Coatings. The coatings shal! be tightly adherent, smooth,continuous, and free from pits, blistersnodules, and any other defects which would interferewith their protective value and serviceability, All toolsshall be chrome plated,oxide or phosphate coated, orhave the manufacturer’s standard coating
4.7.2.1 Chrome Plate. The coatings shall beelectro-deposited metals consisting of nickel followedby chromium. The minimum thickness shali be 0.00015in. for nickel or iron-nickel. and 0.000003 in. forchromium.
4.7.2.2 Oxide Coating or Phosphate Coating. Coating shall consist of a chernically producedoxide or phosphate, foilowed with a coating of preser-valive.
4.7.2.3 Alternate Finishes. Wrenches shall be finished in accordance with predetermined requirements bctwccn producer and consumer.