Double-wall hardened abrasion resistant steel pipeline systems for hydraulic and pneumatic mine backfill conveying

A wear resistant pipeline for abrasive solid materials conveying has to have a hardness on the inside of the pipe of approx. 600 Brinell. At the same time, the outside of the pipe should be soft and ductile to withstand dynamic stresses. Moreover, the pipe should be lightweight for easy handling and installation. These physical features are built into the Solidresist 600 pipe by manufacturing the pipe from two different steel grade materials. After the hardening of this double-wall pipe, the result is a lightweight pipe, which combines two extremely diverse physical properties -high hardness and ductility – in a thin pipe wall. This paper presents a description of the manufacturing process and illustrations of the pipeline systems including special fittings and accessories for mine backfill operations.