... structure scaffolding system, frameISO9001, CE certificatescaffolding pipe, including ERW and Seamless, round and rectangular or square, aew ... according to standards ASTM A53, ASTM A106, ASTM A795, ASTM A135, ASTM A500, API ... tube, scaffolding tube, water transferring tube, oil pipe, casing pipe, sprinkler fire fighting system tube (with groove available ...