Materials
The fittings of TECHNIMA range are Injection moulded, using polyethylene polymers suitable for pressure pipelines for the distribution of Gas, Water and other fluids. Their characteristics are in conformity with the Greek and International standards (ISO 4437, prEN 1555-3, prEN12201-3). The PE raw materials which are used are suitable for drinking water. In black fittings carbon clack is added for UV stabilization. All fittings can be manufactured using PE 80 or PE 100 polyethylene polymers coloured black, yellow and blue. TECHNIMA’ s fittings are weld able with PE pipes having density 930 – 952 kg/m3 (ISO 1872 – 1972) and melt flow rate 0,4 – 1,3 g/10 min, with load 5 kg (ISO 1133).
Principles of fusion
Electrofusion is a method of jointing PE pipes using fittings with integral heating elements. Sockets are used to join main pipes and spigot fittings and saddle fittings to connect services to mains. The pipe to be joined must be prepared by removing the outer surface layer to a depth of around 0,2 mm, the pipe and fitting are clamped together to prevent movement. A voltage is applied across the fitting terminals via a control box giving <_ 40 Volt. An electric current is passed through the wire which melts the polymer and fuses the fitting to the pipe. After welding, the joint is allowed to cool before removing the restraining clamps.
Pipe / Fitting selection
Check that both pipe(s) and fittings to be joined are the same size and material. Only compatible materials should be joined together. If in doubt, seek advice from the pipe of fitting manufacturer.
Pre-joint checks
Use only equipment which has been regularly serviced and is in good condition. Check that restraining clamps and liners are correct and are clean. Check that scrapers are clean and the blades are sharp.
Making socket joints
Preparation pipe’s edges
- Cut or check that the pipe ends are square to the center line.
- Wipe loose dirt from pipe ends with clean, dry, lint-free cloth or paper towel.
- Scrape pipe ends completely in length at least the fitting length.
- Wipe off loose swarf with clean, dry lint-free cloth or paper towel.
DO NOT TOUCH THE PIPE ENDS OR ALLOW SURFACES TO GET DAMP PRIOR TO CONTINUING If for any reason the pipe ends become dirty or damp, clean again using clean lint – free degreasing cloth and cleaning fluid (trichloroethane or Tangit Cleaner).
Coupler installation
- Place the one prepared pipe into restraining clamp.
- Open fitting bag, check the fitting is clean and place over piped and push up until the fully length of socket.
- Place the other prepared pipe into restraining clamp until the two pipes are in contact.
- Mark the penetration depth on the second pipe L/2 (where L = length of fitting).
- Push the socket to pass over the second pipe to reach the mark.
Making the weld
- Check generator haw sufficient fuel.
- Start the generator and leave it running without load for 1 minute.
- Plug the control box input lead into the generator output socket.
- Connect the control box output leads to the fitting terminals.
- Check that the welding time and welding voltage marked on displayed on the control box display.
- Press the «START» button in control box in order to start the welding.
- When the welding cycle is complete check the welding indicator have risen.
- Allow weld to cool for the full time started on barcode label of the fitting before removing clamps and moving the assembly.
Making sadle joints
- Expose pipe to which saddle is to be welded.
- Remove loose dirt from the pipe with a clean, lint-free cloth.
- Mark pipe surface 10 mm clear all around contact area.
- Scrape the pipe uniformly over the entire surface within the marked area.
- Wipe away any loose swarf with a clean, lint free cloth or paper towel.
- Do not touch with fingers the welding surface.
- Remove fittings from bag.
- Clean again the welding surfaces with lint free cloth or paper towel using or proper degrease liquid (Tangit cleaner).
- Place the U/P (Under Part) of the fitting and the saddle in position using the bolts. Screw the bolts using screwdriver uniformly until the saddle is square firmly on pipe.
Welding
Follow the procedure for welding described in chapter «Making the weld»
Welding quality
Check the fusion indicator have risen. Check that no melted material or wire has exuded from the fitting. Check that saddles are square on pipe.
Making outlet joint
Follow the procedure described previously. Scrape outlet of tapping tee and service pipe with appropriate size mini-scraper. Align service pipe and fittings with restraining clamp. Make the weld as before. After appropriate cooling time and the additional 15 minutes unscrew cap from saddle and using cutter key, insert into integral cutter tap the main, retract cutter until top is flush with stack and refit the cap.
Attention: The cutting in the pipe must be done after the cooling period of the saddle has ended and not before that
Do not use spanners to tighten cap. This may damage the threads and cause leakage.
