INSTRUCTIONS FOR WELDING ELECTRO FUSION FITTINGS
Electrofusion fittings can be used to connect Pexgol cross-linked polyethylene pipes. The pipes and fitting are connected by means of fusion welding creating a leak-proof seal. There’s no need for a sealing ring. During the electrofusion process a current is transported through a heating wire.
The surrounding material around the wire is melted and welds the pipe to the fitting.
Some of it advantages are:
- Electrofusion system is one of Pexgol’s connector systems, providing all connection technologies for Pexgol pipes.
- Electrofusion fittings are the main means of connection in municipal water and industrial distribution systems.
- Fittings are tested and have a lifetime of 50 years, according to the European standards a working pressures of 16 atm in water networks.
- Lightweight and small volume welding connectors.
- Economical use especially for big diameters in water transportation.
- Connectors are offered in diameters ranging from 20 mm to 630 mm as well as in a wide variety: couplers, elbows, end plugs, Tees, saddles, tapping saddles (for connecting new outlets to “live line”).
The entire electrofusion process is executed and fully monitored by the computerized control box ensuring safe, reliable connections.
Installation instructions for electrofusion fittings:
Installation can be performed only by trained workers who have received a valid certificate showing that they have been trained by a person authorized by Pexgol.
Use only electrofusion fittings approved for fusion with Pexgol cross-linked polyethylene pipes.
Wall thickness defined as follows:
25 – 75 mm pipes, minimum S.D.R. 11
90 – 355 mm pipes, minimum S.D.R. 16.2
Pressures:
PN 16 electrofusion fittings are suitable for working together with Pexgol pipes which are rated up to pressures of P.N. 15 in water or 10 bars in gas (only PE spigot connectors are produced in two levels, P.N. 10 and P.N. 16).
Rounding the pipe:
For a quality fusion and for easy insertion, rounding the pipe is compulsory. This is achieved by using rounding tools which are placed on the pipe end. The tools maintain a rounded pipe during the welding process.
Support of the fitting during the welding process:
When welding pipes in diameters 90mm and higher, the pipe should be inserted into the fitting by means of spanners (come-alongs) which allow controlled insertion and ensure the coupler does not move during the welding process.
Cooling time:
Please note the cooling time that appears on a sticker on each fitting. Do not disassemble spanners and rounding devices until the cooling time has elapsed.
A good practice: when the fusion process is completed, note the hour and add the cooling time. The result is the disassemble time. Mark this time on the fitting and do not disassemble it earlier than this time!
Pexgol electrofusion fittings are allowed for use at the following temperatures:
| Pipe Class (P.N.) | Temperature |
|---|---|
| 16 | 20ºC |
| 14.4 | 25ºC |
| 13 | 30ºC |
| 11.5 | 35ºC |
| 9.9 | 40ºC |
| 8.3 | 45ºC |
| 6.9 | 50ºC |
In case of higher pressures please consult the Pexgol Field Service.
Preparations:
- Preparing the fittings for welding: Preparation and welding can be conducted at ambient temperature if the weather is windy (with dust) or rain or other sources of humidity, the welding area should be protected by a cover or welding should be halted until the weather conditions are suitable.
- Preparation (cleaning and scrubbing) must be done close to the welding time. Do not prepare pipes and fittings for welding if you plan to weld at a later stage.
- Scraping and peeling of the pipe: universal or hand scraper must be in perfect working condition with a sharp blade. The blade in the universal scraper should be replaced when no longer sharp. The blade of the hand scraper should be sharpened from time to time using a fine iron file.
The thickness of the scraped layer should be as follows:
- Diameter: 20-25 mm, 0.15–0.20 mm
- Diameter: 32-75 mm, 0.15-0.25 mm
- Diameter: 90–355 mm, 0.20–0.30 mm
