Miniature roller bearing vibration quality inspection standard

The evaporative (miniature roller bearing grease C) Said in the long-term use under condition of high temperature grease, grease oil volatilization, evaporative as small as possible. The evaporative mainly depends on the nature of the lubricating oil and fat fractions. Oxidation stability is refers to the grease when used in long-term storage or long-term high temperature resistance to heat and oxygen, permanent changes in their ability to maintain its nature will not occur. Due to oxidation, are often free alkali content reduced or free organic acid content increases, drop point drop, dark appearance, appear different smell, consistency, ultimate strength, similar viscosity decreased, generated corrosive product and destroy the material of grease, soap oil separation. In long-term storage of grease, therefore, should be stored in dry and ventilated environment, prevent sun, and shall regularly check free base or free change of the project such as organic acid, corrosion resistance, to ensure its quality and performance. Vibration acceleration national standards ( Commonly known as Z standard) The standards early, in order to measure the vibration of the bearing rotates acceleration value, to determine the quality of the miniature roller bearing level, divided into Z1, Z2, Z3 from low to high quality grade three. At present domestic bearing manufacturers still use to vibration acceleration value to measure the pros and cons of bearing, simply reflects the fatigue life of bearing. The vibration velocity standard ( Commonly known as V standard) Because the original vibration acceleration standard has not been abolished, the standard has emerged as ministerial standard of mechanical industry, is a reference European standard combined with the actual situation in our country and the need to develop, to detect bearing vibration velocity to differentiate bearing the quality levels of ( Equivalent to the national standard) 。 : V, V1, V2, V3 and V4 five levels of quality. All kinds of ball bearing quality level from low to high V, V1, V2, V3 and V4; Roller bearing ( Cylinder and cone) From low to high quality grade V, V1, V2, V3 four quality grades. It was based on the different frequency (bearing Low frequency, intermediate frequency and high frequency) The vibration velocity to reflect the quality of the bearing. The analysis of the bearing can be roughly whether geometry problems ( Such as rims ellipse) , race/the quality problem of the rolling element and cage's quality problem, than to vibration acceleration to examine quality has improved significantly in miniature roller bearing. Export to Europe to the current domestic bearing, the military and aerospace industry in China are conducted in accordance with the standard bearing quality inspection, testing at the same time the European bearing quality and identify counterfeit bearings provides a feasible method. The miniature roller bearing quality testing situation of two parallel standard and quality is high level of the Z standard of the bearing, with the 'V' when testing may not have a good quality performance, there is no corresponding relationship between both. In the bearing is to pay special attention to the quality inspection.