รายละเอียดเอกสาร

This specification covers four different grades of round and shaped plain carbon and alloy steel spring wire, uniform in quality and temper, intended for the manufacture of mechanical springs that can withstand moderate fatigue stresses over some relatively low number of cycles. The quality level is between the commercial quality grades of wire such as Specifications A401/A401M, A231/A231M, and A229/A229M and the valve spring quality grades such Specifications as A230/A230M, A232/A232M, and A877/A877M. It is similar to the grade TD (referenced in EN 10270-2) intended for medium fatigue levels, such as required for clutch springs. This wire shall be either in the annealed and cold-drawn or quenched and tempered condition as specified by purchaser.

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