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771.14 Spot Painting of Bearings and Piling

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Code: R327

Spot painting of bearings and piling is done to protect the bearings and piling from rusting. The work is scheduled April to November weather permitting with temperatures above 40 degrees and dry conditions.

Materials

  • Calcium sulfonate primer or penetrating sealer
  • Gray or green calcium sulfonate topcoat
  • Blasting sand or abrasive
  • Paint products available in aerosol cans

Procedure

1. Remove all paint scale, pack rust, and other surface rust by sandblasting, scraping, grinding, or wire brushing.

2. Prime exposed steel with rust resistant primer using paint sprayer or brush immediately following prep work.

3. When primer has dried, apply topcoat with paint sprayer or brush.

Safety

Where lead based paint exists take proper precautions to collect and properly dispose debris.

Instructional Photographs

The steel piling and bearings exposed to the environment are very susceptible to corrosion. Corrosion on the members may reduce their load carrying capacity or their structural function. Painting these elements will lengthen the life of the structure.
771.14 Spot Painting of Bearings and Pilings1.jpg
Rust on the bearings restricts the movement of the bearings and increases the stresses in the beams and the substructure.
771.14 Spot Painting of Bearings and Pilings2.jpg 771.14 Spot Painting of Bearings and Pilings3.jpg
As channels erode or deepen steel piling may become exposed. The steel may not have any protective coating and the corrosion may result in a reduced load carrying capacity.
771.14 Spot Painting of Bearings and Pilings4.jpg 771.14 Spot Painting of Bearings and Pilings5.jpg
These are examples of very clean abutment caps and freshly cleaned and primed bearings.
771.14 Spot Painting of Bearings and Pilings6.jpg 771.14 Spot Painting of Bearings and Pilings7.jpg