2.The base oils of SAE 85W/90 vehicle gear oil and 220# industrial gear oil were obtained by blending Jingmen hydrogenated base stock HVI 500N and non-hydrogenated brightstock MVI 90BS in the right proportion, and adding pour point depressant and viscosity improvers viz.
3.BrightStock Refined，high viscosity lubricating oil usually made from residual stocks by suitable treatment，such asa combination of acid treatment or solvent extraction with dewaxing or clay finishing.
4.BrightStock Refined,high viscosity lubricating oil usually made residual stocks by suitable treatment,such as a combination of acid treatment or solvent extraction with dewaxing or clay finishing.
