Con-Serv Inc
 

High Load &
High Temperature Expansion Bearings:
Bronze, Meehanite, Graphite

 

A. Self-Lubricated Bronze Bearings

CON-SERV offers a variety of alloys which are approved for nuclear, structural, industrial and bridge applications.

These bronzes are lubricated to approximately 25% of the bearing surface. The standard lubricant takes temperatures to 250°F.

Lube 1 has a temperature range from 250°F to 500°F. Lube 2 has a temperature range from 500°F to 800°F. For nuclear applications (normal containment, atmosphere including borated water spray, and radiation below 2.2x106 rads). Use Lube AE for all temperatures to 800°F. Slots and holes if required shall be fabricated in the bearing manufacturer's plant.

Designers us .15 as a practical figure and increase this for high temperature applications (greater than 500°F). Any mating steel surfaces should be finished to a 63 to 125 RMS.

Bronze bearings are cast, machined and lubricated. Edges should be specified "as-cast" or machined.

For alloy C90500 Modified, the maximum design pressure is 800 psi at 600°F. For alloy C86300, the maximum design pressure is 1000 psi at 800°F. A straight-line interpolation is appropriate between the 250°F design pressure and the maximum use temperature pressure.

B. Meehanite Bearings

Generally used for temperatures from 500°F to 800°F.

This material is a form of gray cast iron which is produced utilizing flake graphite. For Meehanite sliding against a ground steel plate (12 RMS to 20 RMS) a design friction factor of 15% is appropriate.

Grade Type GA50 (50,000 Tensile Strength) is usually specified for bearing applications. For lubricated Meehanite, the following design pressures are appropriate at the respective temperatures indicated.

7000 psi @ 500°F
5000psi @ 600°F
3000 psi @ 700°F
2000 psi @ 800°F

The following information is representative of cast alloys used for expansion bearing plates:
Type ASTM
Specification
Former
Alloy No.
Recommended
Design Pressure
at 250°F
Max. Use
Temp.
(Cont.)
Hi-Tin Bronze B22 Allow C91300 A 3000 psi 250
Hi-Tin Bronze B22 Alloy C91100 B 2500 psi 250
Hi-Leaded Tin Bronze B22 Alloy C93700 C 1000 psi 450
Leaded Bronze B22 Alloy C90500* D* 2000 psi 600
Manganese Bronze B22 Alloy C86300 E 3500 psi 800
Aluminum Bronze B148 Alloy C95400 9C 2500 psi 600

Airport Industrial Park

685 Aviation Blvd.

Georgetown, SC 29440

Phone 843.546.1044

Email: sales@con-servinc.com