ASME B18.8.1 pdf download Clevis Pins and Cotter Pins (Inch Series)
2.2.3 Clevis Pin Head Periphery. The periphery ofthe head shall be within a circular runout equal to 12%of the maximum head diameter or 0.020 in., whicheveris greater, with respect to the axis of the shank, as deter-mined over a length under the head equal to the nominalpin diameter.
2.3 Clevis Pin Lengths
All clevis pin sizes are available in a variety of nominallengths. Table 2 provides a means of determining thecotter pin hole location, M, for all nominal pin lengths,G, for each clevis pin size.
2.3.1 Clevis Pin Measurement.The G and M lengthsof the clevis pin shall be measured, parallel to the axisof pin, from the bearing surface of the head.
2.4 Clevis Pin Hole
2.4.1 Clevis Pin Hole Location. The clevis pin holelocation is dimension,M.
2.4.2Clevis Pin Hole Alignment and Angularity. Theaxis of hole through the shank shall not be offset fromthe axis of pin by more than 0.010 in. for the 346-in. and/4-in. nominal pin size and 0.020 in. for all larger pinsizes,and shali be square with the axis of pin within2 deg.
2.4.3 Clevis Pin Hole Chamfer.The hole shall bechamfered or edges otherwise relieved at both ends toremove all burrs and sharp edges.
2.5 Clevis Pin Material and Heat Treatment
Unless otherwise specified by the purchaser, clevispins shall be made of either low or medium carbon steel.When case hardened pins are specified, they shall beresistant to a No. 58 file in accordance with SAE J864.In the event of dispute, case hardness and depth shallbe evaluated by micro-hardness according toASTM E384.The case hardness shall be a minimum of633 HV (HRC 57) with a depth between 0.010 in. and0.016 in.
2.6Clevis Pin Finish
Clevis pins shall normally be furnished with a plain(as processed) finish, not plated or coated. Other fin-ishes, where required, shall be subject to agreementbetween the manufacturer and the purchaser.
Finishes such as the following are suitable for use onclevis pins:
a) Electroplating per ASTM B633 or F1941 (cadmiumis not a recommended finish)
(b Hot dipped zinc coatings ASTM A153 or F2329(c) Passivation of corrosion resistant pins perASTM A380
2.7 Clevis Pin Workmanship
Clevis pins shall be free from burrs, loose scale, sharpedges, and all other defects affecting their serviceability.
2.8 Clevis Pin Designation
Clevis pins shall be designated by the following data,in the sequence shown:
a) product name (noun first)(b)ASME B18.8.1
(c) nominal size (fraction or decimal equivalent)(d) length (fraction)
f) protective finish, if requiredExamples:
(1) Pin, Clevis，ASME B18.8.1,1%× 3/4,Steel,Zinc Plated,ASTM F1941,Fe /Zn 5AT
(2Pin, Clevis,ASME B18.8.1,0.375 × 1%k, Steel, Case Hardened,
2.9 Clevis Pin Marking
Case hardened pins shall be marked with a capital“H” located in the center of the top of the head. Themanufacturer’s identification mark shall also be locatedanywhere on top of the head. Marks may be raised orindented.
3GENERAL DATA – COTTER PINS3.1 Cotter Pin Application
The cotter pins specified are intended for use withclevis pins contained herein and in pinned bolt and nutassemblies or other type of free-fitting pinned assem-blies in general applications.
3.2 Cotter Pin Head Design
A degree of leeway shall be permissible in the designof the head provided; however, the specified minimumoutside diameter is maintained as specified in Table 4.3.3 Cotter Pin Length
3.3.1 Cotter Pin Measurement. The length of pin,L, shall be measured, parallel to the axis of the pin, fromthe plane of contact of a gage (see Fig. 1) with the headof the pin to the end of the prong or pin as depicted inthe illustrations for the respective points types.The gageshall have a hole equal to the specified gage hole diame-ter (see Table 4) within a tolerance of 0.001 in. Thepermissible break or rounding at the gauging edges ofgauging holes shall not exceed 0.005 in.The pin shallbe inserted into the gage with finger pressure (force notto exceed 8 oz).
Where pins having point types other than those illus-trated herein are gauged, the length,L,shall be measuredfrom the plane of contact of the gage with the end ofthe shortest prong.
3.3.2 Cotter Pin Tolerance on Length. The toleranceon length of cotter pins shall be as specified in Table 3.