scope:

This specification details the requirements of a butyl sealing tape used as a physical barrier to prevent corrosion between dissimilar materials. Tape must be composed of a homogeneous material free of air, lumps, unmixed particles and foreign materials. The material shall be asbestos free and easily removed from its backing paper.

Material must have good adhesion to oily substrates including Cold Rolled Steel (CRS), Electro-galvanised (EG), Hot Dipped Galvanised (HDG), zinc anneal and Aluminium. The butyl sealing tape must expand during E-coat oven, protecting the sealant/E-coat boundary from undercutting corrosion. There are two types of this material:

Type 1: Butyl material with both sides tacky

Type 2: Butyl material with one side tacky and the other side containing a compatible non-tacky layer for ease of application on the production line