Installation Supervision

COSMEC INC’S RECOMMENDATIONS FOR INSTALLATION OF BEARINGS

1. Care shall be taken to ensure that bearings at the jobsite are stored in a dry sheltered area free from dirt or dust until installation.

2. Removal of sole and top plates of bearings for separate attachment to the structure is not permitted except under the direct supervision of the manufacturer and by permission of the Engineer.

3. Bearings shall be evenly supported over their upper and lower surfaces under all erection and service conditions.

4. Bearings shall be lifted by their undersides only, or by specially designed lifting lugs.

5. When installing bearings, care shall be taken to avoid damage to and contamination of the bearing’s surfaces.

6. Align the centerlines of the bearing assembly with those of the substructure and superstructure. On guided bearings special care must be taken to properly align the guiding mechanism with the designated expansion direction of the structure.

7. Bearing straps or retaining clamps shall be left in place as long as possible to ensure parts of the bearings are not inadvertently displaced relative to each other. Care must be taken to remove straps or clamps before any normal structural movement takes place, such as post-tensioning, etc.

8. Set offsets of upper and lower bearing parts as required by contract drawings.

9. Grout (where used) must be placed at even density beneath the entire bearing surface without any voids or hard spots.

10. The mating surface of the superstructure shall be level within a slope of 1:200. There shall be no local projecting irregularities exceeding 1/32”. The surface beneath the bearings shall be flat, horizontal and sound.

11. The Contractor shall repair any damage to bearing finishes following installation.

12. Welding procedures shall be established by the Contractor to restrict the maximum temperature reached by the bonded PTFE surfaces to a minimum of 200^o F and to restrict the maximum temperature reached by the elastomer (Polyether-urethane, Neoprene or Natural Rubber) to 250^o F. Temperatures shall be determined by temperature indicating wax pencils or other suitable means.

13. Load on the bearing at the time of welding shall be restricted to the dead load weight of the beams alone.

14. Particular care should be exercised to mask and protect the PTFE and polished stainless steel surfaces to protect them from blast abrasives and paint application during construction.