GEA Grasso V Series Installation And Maintenance Instructions Manual

4.6 LUBRICATING OILS (choice and recommendations)Caution!In case a Grasso compressor is used inside a GEA Grasso producedchiller, the applicable oils could be limited compared with the oilsmentioned in this chapter for use with NH3 as refrigerant. The oils tobe used will then be specified in the Chiller Product information.Warning!The choice of oil for a refrigeration compressor should be made bytaking into account the entire refrigeration system design andoperation as well as the operating conditions of the compressor.For lubrication of refrigeration compressors, several brands and types of speciallydeveloped lubricating oils are on the market. The choice of oil depends not onlyon its good lubrication properties (viscosity) and chemical stability at theoperating conditions of the compressor, but also on the operating conditions ofthe refrigerating plant (solidifying and floc point, solubility).Grasso has tested and approved for use in its reciprocating-compressors thebrands and types of oil as listed tables below.The choice of the lubricating oil depends on type of refrigerant and the operatingconditions of the compressor.The oil viscosity should always be more than 10 cSt. Assumed is that the oiltemperature at the bearing surfaces = 15 K above crankcase oil temperature.A higher ISO-VG number should be chosen when refrigerant solubility incrankcase is expected.Remarks1. Using ISO VG100 oils to increase viscosity at high expected cranckcase-temperatures makes no sense as the friction-heat will increase that much,that the oil-temperature limit related to the minimum viscosity of 10 cSt willalso be exceeded. Only in case of expected high refrigerant-concentrations inthe cranckcase this viscosity-gradeoil is an alternative!2. Using ISO VG46 oils to meet low pour point requirements is only acceptable ifcoupled to a high viscosity-index of at least 100, otherwise the working limitsare so limited (again concerning the minimum required oil-viscosity of 10 cSt)that it can be used in medium evaporation-pressures, making no sense to usethem al a low pourpoint alternative!Hint!Some of the oil types listed in the tables may be marketed under othernames and/or designations; these oils can also be used, providedtheir identity can be proved beyond any doubt. Application of other/alternavive oils is not permitted without the written consent of Grasso.4.6.1 STRONGLY RECOMMENDED OIL TYPESAPPENDIX; Product Information (PI)LUBRICATING OILS (choice and recommendations)0089288gbr_1158 30.10.2017