Structure and application of Bridge spherical bearings
Key words: Spherical bearing manufacturer, spherical bearing structure
The spherical bearing used on bridge,the loading capacity can be produced during 1500-60000 KN, The structure, specification, technical requests, material performance requests of bridge spherical bearing needed to be comply with regulatory requirements.
The bridge spherical bearing is Capable of withstanding vertical loads and rotating in all directions, it can be generally classified according to its horizontal displacement：fixed type spherical bearing, guided type spherical bearing and multidirection spherical bearing, or free sliding spherical bearings
1. The structure of bridge spherical bearing
Normally, the structure are composed of top plate with stainless steel plate, PTFE plate or wear plate,spherical crown plate,Spherical PTFE board,and bottom plate , and Dust proof structure.
2. Technical requirement of spherical bearing for bridge
The capacity of the bridge bearing
Under the designing vertical loading, the vertical compression deformation ≤1% of the total height of the spherical bearing.
For the fixed type and guided type spherical bearing, the Horizontal bearing capacity design value ≥10% vertical loading capacity.5201 silicone grease is added between stainless steel plates and PTFE plates to provide lubrication, under the vertical laoding, the frictional coefficient is different under different temperature :
During -25℃-60℃, the frictional coefficient is 0.03
During -40℃-25℃,the fricitional coefficient is 0.05
3. The material performance of bridge spherical bearing
PTFE plate: It should be made of pure polytetrafluoroethylene board by molding, and cannot use turning boards, recycled materials, and molding pressure should be ≥30Mpa
Silicone lubricant: 5201 silicone lubricant should be used, and it should meet he standard requests
Stainless steel plate should be Mirror stainless steel and performance meet the standard request
Other steel plate , top steel plate and bottom plate should be used S 355JR series steel and meet the ISO request
Crown shaped liner with convex spherical surface treatment: the treatment of spherical crown can be covered with stainless steel plate or Electroplating hard chromium treatment. When the environment of the bridge spherical bearing is Severely corrosive environment , the treatment should be stainless steel pate covered.
If the middle spherical steel plate is plated with chromium, there should be no pores, shrinkage cracks, or scars on the surface,Chromium plating thickness≥100μm，
If the middle spherical steel plate is covered with stainless steel plate, The surface of the wrapped stainless steel plate should not have wrinkles,And it is tightly covered without any voids.
The structure and materials of spherical bearing should be strictly according to international standards, after production, it should be tested depending standards or clients requests.
