ASTM A 503 Standard Specification for Ultrasonic Examination of Forged Crankshafts

Scope:

This specification covers the test equipment required and the procedure to be followed for the examination. Also, it defines the critical and non-critical areas and the limit of acceptance. This specification is used to evaluate the solid forged crankshaft as well as the continuous grain flow crankshaft for medium and high-speed diesel engines.  

Test procedure:

In this specification, the detailed procedure is defined for examination, as per this method initially the crankshaft is examined after heat treatment but before machining geometric features Such as chamfers and oil holes are examined. As per the requirement from the order, surface roughness is maintained at 250 µm.

Video 01: Inspection of a gap of a crankshaft

Test Specimen:

A crankshaft is used as a specimen marked with various scanning zone. Zone 1, Zone 2, Zone 3.

Data:

Indications in all three zones,

Zone 1: Indications equal to or greater than 20 % of the back reflection as established

Zone 2 Indications equal to or greater than 50 % of the back reflection shall be cause for rejection.

Zone 3: Indications equal to or greater than 100 % of the back reflection shall be cause for rejection.

Conclusion:  

ASTM A  503  Specification gives the specifications required for the ultrasonic testing of the forged crankshaft. This specification also gives information regarding the appropriate zone curve that causes the rejection of the crankshaft.