The PVC sheet welding process is basically used  in two sectors.   – Roofing – Sailcloth construction   Although this sector is totally different, the manual welding method is exactly the same.   EQUIPMENT   To perform this welding we need at least the following:   – Manual welder – Flat nozzle – Pressure roller   I attach link where you will be able to see the minimum kit needed.   http://aristegui.info/en/blog/espanol-kit-manual-toldos/   From here on, there are more nozzles and rollers models   WELDING PROCESS   The welding process is simple.   – We overlap the two PVC sheets about 45mm – With the Manual welder we make some quick points to mildly fix them. – We introduce the welder nozzle between the two sheets with an approximate 45º angle and we press with the roller just in front of the nozzle with a forwards and backwards movement. – We move the welder without stopping from pressing with the roller until we arrive to the end of the welding. – The welding speed will be set by the operator according to the temperature that we have set, if we go too fast the sheets will not be welded, and if we go too slowly they will get burnt. – If the material gets burnt we have to either increase speed or lower the temperature, and if we do not weld we must either increase the temperature or lower the speed.   For this type of welding there are four fundamental rules. Similar materials welding Right temperature Pressure Welding speed   Here by we attach a video where you will be able to see this process.