1999JB/T 51125-1999 Quality grading of internal combustion engine cylinder head products
1970JB/T 51125.2-1994 Test method for quality classification of internal combustion engine cylinder head products
JB/T 51125.2-1994 Test method for quality classification of internal combustion engine cylinder head products was changed to JB/T 51125-1999 Quality grading of internal combustion engine cylinder head products.