Field joint coating material and a process for making a field joint

A process of coating a field joint on a steel pipe having at least two pipe sections joined to each other, the process comprising the following steps:

• (i) abrading or sand blasting a bare metal surface of the steel pipe at a position of the field joint;
• (ii) applying a corrosion protective layer consisting of a fusion bonded epoxy on the bare metal surface, then applying an adhesive layer directly on the corrosion protective layer without an intervening layer of epoxy material, wherein the adhesive layer is of an olefin type adhesive is a modified linear low-density polyethylene resin or a modified polypropylene resin, having from 0.2% to 10% by mass of a maleic anhydride graft content;
• (iii) abrading and cleaning end cuts of factory applied parent coating resins;
• (iv) placing a mould around the steel pipe in an area of the field joint to define a cavity between an internal surface of the mould and the field joint;
• (v) injecting a field joint coating material based on a curable olefin liquid formulation in the cavity;
• wherein the field joint coating material comprises:
• (a) at least one olefin monomer or at least one oligomer able to undergo polymerization and optionally crosslinking, and
• (b) a catalytic system able to activate the polymerization and optionally the crosslinking of the at least one olefin monomer or the at least one oligomer.