Retrofits


Bently EPP Gas Bearings are similar to oil based bearings in that they have the same load capacities and size formats. So an oil journal bearing can be replaced with a gas journal bearing without modifications to the stator or rotor components. Bently Gas Bearings are also available in tilt pad deigns; again they may be made bolt for bolt replaceable with original oil bearings. This possibly extends to thrust bearing also.

This means that any compressor, pump, turbine, motor, expander, blower, etc. that uses oil bearings, is a possible candidate for retrofit to gas bearings. It is recognized that if a piece of equipment is running without issue there is no motivation to change. But there are machines that have “issues” with oil. One common issue is that the oil gets too hot and solutions like bigger oil tanks and oil chillers are too expensive or there is no room for them. A switch to gas bearings that can operate at 400c continuously may be a simple solution.

It is not unusual for machines to leak oil, some mysteriously, like where is the oil going? To stop the mess and avoid the future costs, consider a switch to gas bearings as a solution. Oil is flammable and when operating at high temperatures even more so. Large motors and generators often have electrical brushes, and commutators or exciters that could spark. Because oil is not compressible, in loss of power it has only gravity feed. So we put oil tanks over hot turbines! Gas is compressible and even a large machine could run for hours on a single Nitrogen cylinder. This dramatically reduces the size and complexity of back up systems and avoids the fundamental hazard of oil fires.

Using Bently Gas Bearings to replace bearings in a six stage pump
Using Bently Gas Bearings to replace bearings in a six stage pump
Using Bently Gas Bearings to replace bearings in a six stage pump
Using Bently Gas Bearings to replace bearings in a six stage pump
Using Bently Gas Bearings to replace bearings in a six stage pump
The pictures above show drop in replacement of Bently Gas Bearings for a six stage centrifugal pump. The radial gas bearings are journals at 2.5-inch diameter; the axial thrust gas bearings accommodate over 2000 lbs. of load.
One of the options in a retrofit is to directly replace the oil bearings with Bently Pressurized Bearings as noted in the first paragraph and seen in pictures above. Gas supplies can be Nitrogen, compressed air or process “seal gas”, among other options. 100 psi supply will generate 60 psi of unit loading under the bearings. Special high pressure Bently Bearings take supply pressures to 600 psi with a resulting 400 psi unit loading capability.

In some cases it maybe possible to get the gas bearings and seal in the same space occupied by the seal normally. This allows for shortening the shaft, a significant improvement but would also likely require moving the driver. Speaking of seals, New way has also started another brand; New-Seal™. We use our EPP bearing technology to create dry gas seals (DGS) that can be used anywhere. See more about our seal technology:

If we did not lose you with the seal info and you are interested in looking to how gas bearings could be retrofitted into your equipment, please call or send us some basic info on your application. We would be glad to review it with you, carry on to the technical section of the site: