How To Use an Electrofusion Welding Machine

Electrofusion machines are used to weld polyethylene utility pipes together in order to create a secure, permanent joint. This is a handy technique, and an alternative to butt fusion welding. 

Considerations between the two homologation jointing techniques can be: cost, size of pipe, length of installation, complexity of installation (e.g. long straight lengths only or lots of angled connections to complete). Both are highly recognised worldwide as approved techniques for installation.

In this quick guide, we’ll cover the steps involved to operate an electrofusion welding machine, including how the pipes should be prepared, as well as handy tips for a perfect weld and smooth operation. 

Preparation & alignment 

PE pipe surfaces can develop an oxidised outer layer, which can restrict molecular diffusion and result in a weak weld. Removing this layer ensures a reliably welded joint from electrofusion. 

So, the first step is to carefully clean the pipe ends and mechanically scrape them – this is a mandatory step as outlined in the Water Industry Specifications (WIS). Pipe ends must be scraped to the marked point of fusion using a proper tool, such as our PatchMaster and PrepMaster ranges. 

Then, align the pipes and hold them in position with clamps. This ensures that everything is in the correct orientation and won’t move from the transfer of energy from the electrofusion machine to the coupler.

Step 1: Setting up the electrofusion machine 

Once the pipes and coupler are in position and prepared, power up the unit either with a running generator (TIN-12 Specification is recommended) or the mains supply. Then select a welding mode based on your electrofusion welding unit, which will likely be manual, automatic/fusematic, or barcode.

The follow the procedure for the specific unit, if manual you will need to confirm the welding/fuse time and the cooling time. This is generally automated with automatic/fusematic or barcode modes, but care should be taken to check the parameters against the fitting itself.

Note that some electrofusion units and specifications will have and require ambient temperature compensation i.e. an adjustment to the weld timings based on the ambient temperature (up or down). 

The screen on our electrofusion box will show the software version, date, and owner details. This unit can record important information about the weld, such as cooling time, date, location of the weld, and additional operator information. 

Step 2: Heating

The unit will pass a current through the fitting’s internal coils at either 40 or 80 volts. These will heat up and melt the inside of the fitting and the outer pipe surface to form a fused zone. The voltage and time that this step needs for the pipe ends to fuse depends on the material, size/SDR of the pipes and the specification of the electrofusion fitting.

Check whether your specification requires the full cooling phase to be recorded by the machine and if so you will need to leave the output leads connected until this phase is fully complete. Most electrofusion control units will display timings on screen.

Step 3: Cooling 

At the end of the weld, the cooling time will appear on the unit screen. Keep the alignment clamps on during this process, as any early movement may impact the joint. 

This is a crucial final step of the electrofusion welding process, as it allows the new fused pipe to set in place. 

Step 4: Testing

Once fully cooled, carefully unclamp the pipe. You can now carry out pressure tests or non-destructive checks to confirm the quality of the weld, in line with the manufacturer or clients’ requirements. You will be left with a jointed pipe as secure as a continuous length of original pipe. 

Final tips & quality checks

Here are some important things to be aware of when using an electrofusion machine for pipe welding: 

• Most specifications require circa 0.2mm-0.4mm to be uniformly removed, but it can vary depending on welding specification.
• Do not open the box as there is a high risk of electric shock. 
• Don’t operate the machine under challenging weather conditions (such as rain, fog, or snow), without suitable ground and equipment covering, or without using suitable PPE. 
• The welding unit should only be used if in calibration.
• The welding unit must not be used in a gaseous atmosphere due to risk of explosion. 
• Ensure that the work is being completed with a suitable ambient temperature.
• Only those suitably trained should operate an electrofusion machine. 
• It is the operators responsibility to ensure the correct fitting is being welded.
• Do not move or touch the unit, pipes, or fitting during the welding or cooling time. 

Electrofusion machine hire with Hy-Ram

Electrofusion welding has come a long way since it was first used in Europe in the mid-1950s. Since then, the equipment involved has evolved and transformed the process tremendously. 

Our full range of electrofusion machines and equipment is designed to help you tackle different on-site challenges, project specifications, and pipe sizes. The range is available to buy or hire across various sectors worldwide. 

Get in touch with the Hy-Ram team today to discuss our hire options and equipment types.