Pipeline Demagnetizer Rental — Arc Blow Control
Residual magnetism in line pipe deflects the welding arc — arc blow — and produces porosity, undercut and wandering beads that no amount of welder skill corrects. It is one of the few welding problems where the cause is invisible and the crew gets blamed. A demagnetizer removes the cause in minutes.
Request a Quote →At a glance
- Function
- Reduces residual magnetism in pipe ends to a level where the arc stays stable
- When it is used
- Before root pass welding, particularly on tie-ins and cut pipe
- Typical symptom it solves
- Arc blow, porosity, undercut, wandering root
- Used with
- Internal line-up clamps, paywelders, cold cutting machines
Where the magnetism comes from
Line pipe picks up residual magnetism from magnetic particle inspection, from magnetic lifting equipment, from long storage aligned with the earth's field, and from the cathodic protection system on an existing line. That last one is why tie-ins into a live, CP-protected system are the classic arc blow scenario: the pipe in the ground has been sitting in an imposed field for years. If your welders are struggling specifically at tie-ins and not on the mainline, magnetism is the first thing to check.
Cheaper than the repair it prevents
Demagnetizing takes minutes per joint and the hire rate is a small line on a spread budget. Grinding out and rewelding a rejected root on a tie-in — with the excavation open, the crew standing by and possibly a permit window closing — is not. This is the item on the list that contractors most often skip and most often regret.
Measure, do not assume
Demagnetizing without measuring is guesswork in both directions: you can leave enough field to still cause blow, or you can waste time on pipe that never had a problem. The sequence that works is measure the field at the pipe end, demagnetize, measure again, then weld. If your QA/QC procedure does not already specify a threshold, agree one with the client before the spread starts rather than during it.
Pipeline Demagnetizer across the Eastern Province
Usually mobilised alongside
From the general rental fleet
Trades supplied with this equipment
FAQ — Pipeline Demagnetizer
Also known as
Demagnetizer · Demagnetiser · Pipe Demagnetizer · Pipeline Demagnetising Equipment · Residual Magnetism Removal · Arc Blow Control
Spread down? Call.
Tell us the line size, the location and the date. We will tell you honestly what can move and when.
+966 50 752 9347Request Direct Quote
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