... High Frequency welding machine for Tarpaulins,Tents,Billboards, Signs,Truck Covers,Canvas,Membrane. Main Application of High ... truck covers, swimming pool covers, airline hangars, billboards, signs, side curtains and many other general technical fabric joining. ... pool covers3) Tarpaulins, airport hangars, side curtains4) Advertising signs and billboards5) Flood dams and water tanks6) Swimming pools, ...