JB/T 51049-1999Internal combustion engines - Crankshafts - Product quality grading (English PDF)

1 Scope

This standard specifies the product quality indicators, inspection methods and inspection rules for crankshafts for reciprocating internal combustion engines with a cylinder diameter not greater than 200 mm, hereinafter referred to as "crankshafts".

It applies to the inspection and assessment of crankshaft product quality.

This standard is a revision of JB/T 51049-93 "Quality grading of internal combustion engine crankshafts"; the revision was editorial and the main technical content is unchanged. It supersedes JB/T 51049-93 from the date of implementation. It was first issued in 1987 and first revised in 1993, and was drafted by the Shanghai Internal Combustion Engine Research Institute and Wendeng Tianrun Crankshaft Co., Ltd.

2 Normative references

The provisions contained in the following standards become provisions of this standard through reference in this standard. The editions shown were valid at the time of publication of this standard. All standards are subject to revision, and the parties using this standard should consider the possibility of applying the latest editions of the standards listed below.

GB/T 228-1987 Metallic materials - Tensile testing

GB/T 229-1994 Metallic materials - Charpy notch impact test

GB/T 230-1991 Metallic materials - Rockwell hardness test

GB/T 231-1984 Metallic materials - Brinell hardness test

GB/T 699-1999 Quality carbon structural steel

GB/T 1184-1996 Geometrical tolerances - Tolerances for features without individual tolerance indications

GB/T 1348-1988 Spheroidal graphite iron castings

GB/T 1958-1980 Inspection of geometrical tolerances

GB/T 2828-1987 Sampling procedures and tables for lot-by-lot inspection by attributes (applicable to inspection of continuous lots)

GB/T 3077-1999 Alloy structural steel

GB/T 4342-1991 Metallic materials - Micro Vickers hardness test

GB/T 5617-1985 Determination of the effective depth of hardening of steel after induction or flame hardening

GB/T 9441-1988 Metallographic inspection of spheroidal graphite iron

GB/T 11354-1989 Determination of the nitrided case depth and metallographic inspection of iron and steel parts

GB/T 13320-1991 Steel die forgings - Metallographic rating charts and assessment methods

JB/T 6727-1993 Specification for internal combustion engine crankshafts

JB/T 6729-1993 Magnetic particle inspection of internal combustion engine crankshafts and camshafts

JB/T 9204-1999 Metallographic inspection of induction-hardened steel parts

JB/T 9205-1999 Metallographic inspection of induction-hardened pearlitic spheroidal graphite iron parts

JB/T 9773.1-1999 Diesel engines - Methods of assessment for bench tests

QC/T 525-1999 Reliability test methods for automotive engines

3 Quality indicators