2200LZJE-HO-C6-N_2013.12.
Chapter 5 Maintenance
Compound 2-stage Screw Compressor 2016**C
5.3 Management of Lubricant
5-6
5.3
Management of Lubricant
5.3.1 Lubricant Management Criteria
Lubricants, to which the management criteria applies, are classified as follows.
1. Synthetic oils : Polyalkylene glycols (PAG)
2. Mineral oils : Naphthenic base and paraffinic base
3. Synthetic oils : Alkyl benzene (AB) and Polyalphaolefine (PAO)
4. Synthetic oils : Polyolesters (POE)
We recommend performing sampling oil analysis every six months.
If the oil does not satisfy the management criteria below, replace the oil.
* This does not apply to water contents in PAG oil. See Note 1 of the table below.
Items and criteria are as follows. The management criteria may be changed without notice.
Table 5-5 Synthetic Oil (PAG)
Item
Management Criteria
(a) Color
ASTM color standard: 4.0 or less
(b) Total acid number
(TAN)
Max. 0.1 mg·KOH/g
(c) Kinematic viscosity
Within ±10% in variation when compared with fresh oil
(d) Water content
Max. 2000 ppm
Note 1
(e) Contamination level Max. 15 mg/100 ml as measured by gravimetric (Millipore filter) method
Note2
Table 5-6 Mineral Oils and Synthetic Oils (AB, PAO)
Item
Management Criteria
(a) Color
ASTM color standard: 6.0 or less
(b) Total acid number
(TAN)
Max. 0.3 mg·KOH/g
(c) Kinematic viscosity
Within ±15% in variation when compared with fresh oil
(d) Water content
Max. 100 ppm
Note 1
(e) Contamination level Max. 15 mg/100 ml as measured by gravimetric (Millipore filter) method
Note2
Table 5-7 Synthetic Oil (POE)
Item
Management Criteria
(a) Color
ASTM color standard: 4.0 or less
(b) Total acid number
Max. 0.2 mg·KOH/g
(c) Kinematic viscosity
Within ±10% in variation when compared with fresh oil
(d) Water content
Max. 200 ppm
(e) Contamination level Max. 15 mg/100 ml as measured by gravimetric (Millipore filter) method
Note2
Note 1: Synthetic oils (inter-soluble with ammonia) are so highly hygroscopic that they can absorb
moisture at the time of sampling. In addition, the ammonia content they have absorbed may
be detected as the water content at the time of the analysis, making it difficult to precisely
measure the water content. Therefore, use the criterion value only as a reference.
Note 2: This assumes the use of an oil filter with nominal mesh size at 15
μ
m or finer.