Selection of lubricant for reciprocating metering pumps
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The instructions for reciprocating metering pumps used in chemical enterprises generally specify that 25# transformer oil should be used for lubrication at the piston, while 32# mechanical oil should be used for lubrication in the gearbox. Based on personal experience, it is believed that the former should use 46# hydraulic oil (L-HL46), while the latter should use 68# gear oil (L-CKC68). I’m not sure if this is correct Everyone is welcome to discuss
“The instructions for reciprocating metering pumps used in chemical enterprises generally specify that 25# transformer oil should be used for lubrication at the piston, while 32# mechanical oil should be used for lubrication in the gearbox. Based on personal experience, it is believed that the former should use 46# hydraulic oil (L-HL46), while the latter should use 68# gear oil (L-CKC68). I’m not sure if this is correct ” I think: neither of the two is correct! 1. Transformer oil is generally classified based on its freezing point, which is indicated by the oil’s “grade.” For example, grade 25 means that the oil freezes at -25°C. This designation has a completely different meaning from the “#” used in the old standards for mechanical lubricants. Kinematic viscosity of transformer oil: 9.936 mm2/s at 40°C; therefore, 46# hydraulic oil (L-HL46) cannot be used instead ； 2. The original oil used in the gearbox was 32# mechanical oil; it should actually be N32 mechanical oil, as there is no 32# mechanical oil under the old designation – only 30# mechanical oil is available. However, some manufacturers currently confuse the old and new standards, so L-AN32 mechanical oil can be used. If hydraulic oil is chosen, then L-HL46 hydraulic oil can be used.
The oil used in our company’s metering pumps is grade 68, and it delivers excellent performance.
I'm sorry! I made a mistake; if hydraulic oil is to be used, L-HL32 hydraulic oil can be used.