Pipe end preparation
Large-diameter misalignment grows once pressure builds, so clamps, rollers and centring are set before the first cut. Moisture, grit and oily residue can spoil the melt face, especially on coastal work where humidity hangs around and dirt sticks to wet pipe. Each step has to be set up before the next one starts.
- Check the pipe grade and wall thickness before setting the machine.
- Make sure there is no mud, water or loose shavings in the work area.
SDR and size change the settings
SDR tells you how thick the wall is compared with the outside diameter, and that changes the heat soak, pressure and cooling window. Thin wall pipe heats faster and needs careful control, while thicker wall pipe asks for more time at temperature and a longer hold under fusion pressure. A machine set for 110 mm pipe will not be used the same way on 315 mm or 630 mm, because the mass of material and the force required are very different. That size jump is where setting errors are most common.
Wall ratio, pipe diameter and ambient conditions all shape the weld sequence, so the operator sets the machine from the weld chart for each job.
The heating face and changeover window
Plate temperature must be in range before contact, followed by full face contact for the soak period. Softened faces skin over if the changeover gap drags. Even pressure forms a clean bead without squeezing melt out too far.
- Watch the timer for soak, changeover and cooling stages.
- Use steady pressure and avoid a sudden hard shove.
What bead inspection tells the crew
A lopsided bead can point to poor alignment, weak heating or movement during cooling. Where access allows, check the inside bead, because an off-centre weld can narrow the bore. Crews working on long runs often build bead checks into handover, so problems are spotted before the line gets buried or put back under service.
A visual check after each weld picks up a poor setup before the next joint is made, so fewer joints are cut out and redone.
Data logging and paper trail on site
Customer weld logs usually hold pipe size, SDR, machine number, operator, set point, fusion pressure and the cooling period. The joint record shows what was done on each weld, so several teams can share one trench line without mixing up joints. It also gives supervisors a cleaner way to compare joints, spot a recurring issue and link the machine setting to the finished bead. Where logging is handled properly, the site team has a firmer record when a joint needs review.
- Record the date, location and joint number.
- Keep a simple note of any rework or rejected joints.
Helping contractors narrow the job
Some crews are sorting a new install, others are checking a heater plate before a long run. Pipe size, site access, logging needs and the length of the job, from a short repair to a longer run, all shape the right choice.