Lubricating Oils (Choice And Recommendations); Strongly Recommended Oil Types - GEA Grasso 5 Installation And Maintenance Instructions Manual

4.6

LUBRICATING OILS (choice and recommendations)

For lubrication of refrigeration compressors, several brands and types of specially
developed lubricating oils are on the market. The choice of oil depends not only
on its good lubrication properties (viscosity) and chemical stability at the
operating conditions of the compressor, but also on the operating conditions of
the refrigerating plant (solidifying and floc point, solubility).
Grasso has tested and approved for use in its reciprocating-compressors the
brands and types of oil as listed tables below.
The choice of the lubricating oil depends on type of refrigerant and the operating
conditions of the compressor.
The oil viscosity should always be more than 10 cSt. Assumed is that the oil
temperature at the bearing surfaces = 15 K above crankcase oil temperature.
A higher ISO-VG number should be chosen when refrigerant solubility in
crankcase is expected.
Remarks
1.
2.
4.6.1

STRONGLY RECOMMENDED OIL TYPES

Strongly recommended oil types for Grasso reciprocating compressors
Refrigerant used
0089288_imm_v_english_19
07.04.2021
Hint!
In case a Grasso compressor is used inside a GEA Grasso produced
chiller, the applicable oils could be limited compared with the oils
mentioned in this chapter for use with NH
be used will then be specified in the Chiller Product information.
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 will
also be exceeded. Only in case of expected high refrigerant-concentrations in
the cranckcase this viscosity-gradeoil is an alternative!
Using ISO VG46 oils to meet low pour point requirements is only acceptable if
coupled to a high viscosity-index of at least 100, otherwise the working limits
are 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 use
them al a low pourpoint alternative!
Hint!
Some of the oil types listed in the tables may be marketed under other
names and/or designations; these oils can also be used, provided
their identity can be proved beyond any doubt. Application of other/
alternavive oils is not permitted without the written consent of Grasso.
Brand
NH
3
LUBRICATING OILS (choice and recommendations)
Type designation
PR-OLEO® C-MH68A
GEA PR-OLEO® C-MH68A-FG
PR-OLEO® C-MH100A-FG
APPENDIX; Product Information (PI)
as refrigerant. The oils to
3
Food Grade
H2
H1
H1
59