scope:

This document specifies:

- basic principles, testing assembly and the test machine for noise testing of rolling bearing greases;

- symbols used in the test methods BQ+, MQ and NQ.

This document is applicable for testing rolling bearing greases, especially of unused grease.

NOTE Suitable greases are greases of NLGI classes 1 to 3 according to DIN 51818^[6]. Suitable greases for lubrication of rolling bearings are especially greases according to ISO 12924. The test method according to this document delivers meaningful results for rolling bearings; however, it can also be applied for greases in similar applications^[12][13].

^[6] DIN 51818, Lubricants - Consistency classification of lubricating greases - NLGI grades

^[12] Bichler M., Testing grease noise in rolling bearings. Evolution. 2011, 1 pp. 25-28. Available at

^[13] Michiharu N, Research and Development of Lubrication Grease by NSK. NSK Technical Journal Motion & Control (3) 1997, 1-8