Lubricating greases can be defined as solid to semi-fluid products of the dispersion of a thickening agent in a liquid lubricant:

Commodity greases, usually based on lithium, calcium or sodium soaps (including some EP and lithium complex products) are general-purpose, low-cost products produced in large volumes.

High-specification greases, often based on a complex soap, are frequently manufactured with highly refined or synthetic base oils for more demanding applications than can be met with commodity grease products.

Today the performance of greases is described by norms such as DIN 51 502 in Europe and ISO. Ravensberger Schmierstoffvertrieb GmbH marks its greases according to DIN 51 502. RAVENOL greases are used for permanent lubrication of rolling and plain bearings, sliding surfaces, gears / tooth segments, belt automatics and hinges.

DIN 51 502 DESIGNATIONS for greases:

  Grease application
K for bearings and sliding surfaces according to DIN 51 825
G for enclosed gears according DIN 51 826, OG – for open gears
M plain bearings and seals
  Base oils and additives
P EP-additives
F solid additives (graphite, molybdenum disulfide, etc)
E polyester
FK perfluorochemical fluid
HC synthetic-hydrocarbons
PH phosphoric acid ester
PG polyglycol
SI silicon oil
X others

 

MAX. TEMPERATURE AND WATER STABILITY

Additional
class
upper
application

temperature
Behaviour of greases in the
presence of water according
DIN 51 807 at a temp. of
  in °C 40 °C 90 °C
C 60 0 or 1  
D 60 2 or 3  
E 80 0 or 1  
F 80 2 or 3  
G 100   0 or 1
H 100   2 or 3
K 120   0 or 1
M 120   2 or 3
N 140    
P 160    
R 180    
S 200    
T 220    
U over 220    
0 – indelible
1 – weakly washing-out
2 – average washing-out
3 – strong washing-out

 

Classifications of greases by NLGI numbers

NLGI-class Appearance worked penetration in
0,1 mm DIN ISO 2137
Application
000 fluid 445 / 475 Centralized
grease system
and gear
greases
00 semi-fluid 400 / 430
0 very soft 355 / 385 Greases for
bearings
1 soft 310 / 340
2 “normal” grease 265 / 295
3 firm 220 / 250
4 very firm 175 / 205 Block greases
5 hard 130 / 160
6 very hard 85 / 115
NATIONAL LUBRICATING GREASE INSTITUTE (NLGI) - Classification
NLGI 00 and 000 – semi-fluids for centralized grease systems
NLGI 1 – used in winter
NLGI 2 – multi-purpose
NLGI 3 – used in summer