Proceduce for Butt Welding
Polyethlene pipes may be produced to be connected by butt welding method depending on the project. But there are limitations for connection with this welding method in respect to both diameter and wall thickness. Connection with this welding method can be applied to diameters between 50mm and1600mm : and relative to the diameters, to wall thickness from 5mm to 100mm. butt welding process is carried in accordance with DVS 2207 standard.
Matters to Be paid attention in connection of PE pipes with butt welding methods:
- ◊ Heat of the welding environment should not be below 5 C .
- ◊ Wall thickness of the pipes to be connected must be equal, if there is any difference, then the difference must not exceed 10%.
- ◊ Butt welding machine to be used in welding must be certified.
- ◊ Prior to welding process, welding surfaces must be scrapped, oxidation removed and complete contact of welding surfaces must be provided.
- ◊ After scrapping of the welding surfaces. It must be preserved from dirt. If there is any re-dirtying, the scrapping process must be repeated.
- ◊ Prior to being heated with iron, the surface to be welded must be cleance with pure alcohol.
- ◊ Although the weld iron heat is between 200C – 220C, it must be designated regarding the raw material of the pipe and application standard.
- ◊ After the weld process has started, during weld cooling period the connection pressure values of the pipes must be kept equal.
- ◊ Since, the air circulation formed in the pipes accelerates the cooling process of weld, during welding one end of the pipes nust be closed.
- ◊ Before starting welding process the heat values of the machine must be checked and welding must be started 5 mintes after reaching desired heat value.
- ◊ Iron part of the machine and the welding part of the pipe must be cleaned prior to welding.
- ◊ Welding pressure test for pressurized drinking water pipes are applied in accordance with EN 805 standard.