Project Image

Steel Shield Industrial Gears Lubricants are the ultimate protector and energy saver for any gearing system. Gear contacting faces and bearings are treated by unique ABF Technology which enhance the surface hardness and smoothness. The result are: gears last much much longer and energy consumption drop to the minimum. Steel Shield lubricants DO NOT contain any solid additives which can damage your precious gears, because ABF Technology is more advanced than most of the premium lubricants in the market.

Industrial Gear Lubricants

In general, industrial gears include spur, bevel, helical, spiral bevel, worm gears, herringbone, etc. Gear lubricants must be able to satisfy all the possible situations that gears may suffer during operations. Here revewed some examples:

General Gear Oils Types
Designation General Applications
Non Extreme Pressure (EP), Rust & Oxidiation (R&O) Oils

Generally being used in industrial plants that the steam turbine and gearbox share a common lubricant circulating system

Non Extreme Pressure (EP), Anti-Wear (AW) Oils

These lubricants contain zinc based anti-wear additives which should not mix with EP gear oils. Sometimes, they are being used in moderately loaded gear systems which their shafts are parallelly to each other and the energy is not transferred through a right angle turn in the gear set.

Industrial Extreme Pressure (EP) Oils
  • They are commonly being used in heavy loaded system in which their shafts are perpendicular to each other and the energy is transferred through a right angle turn in the gear system, such as bevel and spiral bevel gears
  • They are not suitable for automotive systems as their extreme pressure additive contents are significantly lower than automotive (GL-5) gear oils
  • Industrial EP gear lubricants are known as "Mild" EP oils while automotive EP gear oils are known as "Full" EP oils
Compounded Oils
  • They are only recommended for worm gear systems due to their sliding frictions (between the wheel and the worm)
  • Compound oils which contain fatty additives may be made from older technology if they contain tallow, lard or caster based additives
  • Compound oils which contain synthetic fat-like materials such as polybutenes may be made from newer technology (Of course, they are not newer than Steel Shield ABF Technology!)
  • Their low temperature are limited because tallow, lard and castor composed lubricants are not allowd to freeze due to the agglomeration and settle out of the additives
  • U.S. Steel 224 and the American Gear Manufacturers' Association (AGMA) 250.24 specification are the two major industrial gear oils performance specifications in the world which characterize high quality EP enclosed gear oils
  • EP or friction modified lubricants are not recommended to be used in the following systems: Conveyor gearboxes systems with internal backstops, clutches, etc.

Viscosity Systems Of Gear Lubricants

The ISO System and the AGMA System classified the viscosities of gear oils which only defined monograde viscosities. The selection of the correct viscosity grade is very important in wet sump, splash lubricated gear systems which lubricant is brought upward with the gear and scraped off of the gear side and fed downward thought the bearings when the gear sets rotate. These systems usually have gears submerged in the lubricant inside the gearbox.

Viscosity Classification Systems Comparison Table
ISO Viscosity AGMA (R&O) AGMA (EP) AGMA (Synthetic) SAE Gear Oil
32 0 0S
46 1 1S
68 2 2EP 2S
100 3 3EP 3S
150 4 4EP 4S SAE 90
220 5 5EP 5S SAE 90
320 6 6EP 6S SAE 140
460 7, 7 Comp 7EP 7S SAE 140
680 8, 8 Comp 8 EP 8S
1000 8A 8A EP
1500 9 9EP 9S
3200(1) 10 10EP 10S
4600(1) 11 11EP 11S
6800(1) 12 12EP 12S
190-220(2) 13 13EP 13S


Residual Compound: Diluent type, commonly known as solvent cutbacks are heavy oils containing a volatile, non-flammmable diluent for ease of applications. The viscosities below are for the heavy oil alone:

  • 14R: (428.5-857.0 cSt@100℃)
  • 15R: (857.0-1714.0 cSt@100℃)


  1. ISO grades 3200, 4600 and 6800 do not really exist, but are used in the table to designate the mid-point of the equivalent viscosity range at 40℃
  2. AGMA numbers 13 and above are specified at 100℃)

Viscosity Selection For Gear Systems

In the selection of the correct gear lubricant viscosity, user must consider:

  • Input power
  • RPM
  • Gear pitchline diameter
  • Splash or oil circulation system
  • Number of reductions
  • Shafts orientations (parallel or perpendicular to each other)

High viscosity gear oil is need for high horsepower, low RPM, small gear pitchline diameter, splash oil feed, more reductions and perpendicular shafts gear systems.

AGMA Gear Oil ISO Viscosity Selection Guide (from LubeWorks Ltd.)
Pitch Line Velocity (ft/min) Oil Temperature (℃)
20 40 60 75-80 90
>200 (1m/s) 68 150 460 1500-2200 3200
500 46 100 320 680-1000 2200
1,000 32 68 220 460-680 1000
2,000 46 150 320-460 680
3,000 32 68 220 460
5,000 32 68 150-220 320
6,000 32 46 100-150 220
24,000 (High speed)


  • For spur, helical and bevel gears only, not valid for worm gears
  • Viscosity Indexs are about 100
  • Oil Temperature = Ambient Temperature + 45℃
  • 0.262 x Pinion Diameter (in) x RPM = Pitch Line Velocity (ft/min) of lowest speed mesh
AGMA Worm Gear Oil ISO Viscosity Selection Guide (from LubeWorks Ltd.)
(Enclosed, Cylindrical Drives)
Sliding Velocity (ft/min) Ambient Temperature (℃)
-40 to -10 -10 to 10 10 to 55
(Low Speed or ½ inch radius worm @ 1700 rpm)
220* 460 680
(<2,400 rpm)
(600-3,600 rpm)
220* 460 460


  • Viscosity Indexs are <100
  • * Tip: Consider PAG synthetic for lower temperatures
  • Worm Sliding Velocity = 2 x 3.14 x R X RPM (ft/min)
    where R = Worm Radius in feet of final reduction stage

Industrial gear lubricants must have good low-temperature start-up characteristics to protect gears from wearings. ISO 68, 100, or 150 oils are thinner and good at low temperatures. The ISO is establishing a system for designating multigrade lubricants. Lubricants with viscosity index more than 120 indicate that they are formulated as multigrades. However, the Viscosity Index Improver Additives inside most multigrade lubricants can breakdown (shear) during heavy sliding between the meshing gear teeth contacts. That can lead to a loss of viscosity (possibly 35%) permanently. In order to select the best lubricant for the gear system, the viscosity of the lubricant after shearing is always a key factor to consider.

Synthetic lubricants are definitly good choices for industrial gearing systems because they have high natural viscosity indexs without (or contain lesser) viscosity index improver additives. That means their viscosity losses are lesser while providing high and low temperature characteristics during operations.

Worm gears have more severe wearing problems during cold temperatures. Therefore, compounded oils (e.g. AGMA 7 Comp) are recommended. However, natural animal and vegetable fats based compounded oils should be avoided due to unavoidable low temperature storage and additive separation issues. Extreme pressure lubricants should be avoided as well because thier sulphur additives can corrode yellow metals. Always follow the maintenance manual for the selection of the correct worm gear lubricants.

Steel Shield Lubricants with ABF Technology can protect any industrial gearing systems without any hidden harmful effects. They do not rely on additives to achieve the lubrication purpose. But their abilities are proved to be highly effective by many world-class international companies and reputed laboratory. Contact us for more details and make your own highly efficient systems now.