Medium Duty Common Casters,Medium Duty Pu Caster Wheel,Industrial Caster Wheel,Environmental Castors Wheel BENYU CASTERS & WHEELS CO.,LTD , https://www.benyucaster.com I. Introduction to the test The test is a seven-piece combination (Fig. 1), of which 4 are on-site machining parts and the other three are self-supplied. The processing time is 8h. In the test, the member 1 is a support member, and the member 4 has three V-shapes, two of which are supported by two cylindrical pins on the member 1 and a 60° V shape. The piece 2 has a hole that cooperates with the cylindrical pin of the piece 1 and has a 60° dovetail groove, and the dovetail groove is combined with the 60° V shape of the piece 4.