In brief
Welding a tipper body made of Hardox steel differs from ordinary structural welding: the key factors are selecting a filler wire with lower strength than the base material, controlling preheating and interpass temperature, and relieving the notch at the crack location. Otherwise, the repaired weld cracks again within a few weeks. PHS Magnum welds steel bodies (S235, S355, Hardox 400/450/500) and aluminium bodies (TIG) in our workshop in Chorula.
Why tipper bodies crack
A tipper works in extreme conditions: abrasive aggregate, impacts during bucket loading, overloads, vibration on back roads. A body made of wear-resistant Hardox steel withstands abrasion, but at stress concentration points — corners, floor-to-sidewall transitions, around hinges — fatigue cracks still develop.
The most common mistake is a “quick patch weld” with ordinary wire. The hard, brittle joint becomes the weakest link and cracks right next to the old weld.
How we weld Hardox so it holds
Filler selection
For Hardox we select wires with a lower yield strength than the base material — a more ductile weld absorbs stresses instead of cracking. It is counterintuitive, but it is precisely the “softer” joint that lasts longer in a body exposed to impacts.
Preheating and the heat-affected zone
With thicker plates and grades 450/500 we apply preheating (75–150°C) and control the interpass temperature. This limits hardening and cold cracking in the heat-affected zone (HAZ).
Notch relief
A lasting repair is not just the weld — it is also the geometry: removing the old crack to its full depth, a proper transition radius, sometimes a reinforcing plate. A weld alone, without notch relief, will crack again.
Steel or aluminium
| Body material | Method | Notes |
|---|---|---|
| S235 / S355 | MIG/MAG | standard structural steel |
| Hardox 400/450/500 | MIG/MAG | softer wire, preheating according to thickness |
| Aluminium | TIG | argon shielding, filler alloy selection |
Welding is part of a larger repair
A cracked body often goes hand in hand with other faults: a leaking hydraulic cylinder — see tipper cylinder overhaul, a bent tailgate or a damaged floor of a half-pipe trailer. In our workshop in Chorula we combine welding with hydraulic repairs and anti-corrosion painting — the full scope is described on the tipper and half-pipe trailer service page.
Got a cracked tipper body? Call us for an inspection: +48 602 716 551.
