In brief
Zinc anti-corrosion coating is the most effective method for long-term protection of steel chassis and frame components of silo trailers — zinc acts as a sacrificial electrode (protective anode), protecting steel even after coating damage. PHS Magnum applies cold zinc coating and two-component zinc coatings as part of the anti-corrosion system (zinc + epoxy + PUR 2K) in trailer renovation. Durability of a correctly applied system: 10–15 years.
A silo trailer spends hundreds of days a year on salt-treated roads, in constant contact with water and mud. Longitudinal frame beams, axle mounts, suspension supports — these are the components that corrode fastest. Replacing a frame or axle is many times more expensive than preventive zinc coating every few years.
Why zinc protects better than paint alone
Galvanic protection mechanism
Steel and zinc form a galvanic cell — zinc as the more “active” metal in the electrochemical series corrodes instead of steel. This is cathodic (galvanic) protection — it works even when the coating is mechanically damaged (scratch, chip).
Comparison:
- Epoxy paint alone: after damage (scratch, chip) corrosion progresses under the coating from the damage edge
- Zinc primer (zinc-rich paint) + epoxy: after damage, zinc within a few mm protects the exposed steel through galvanic action
Zinc in a three-layer system
The most effective system for silo trailer chassis:
- Blasting Sa 2.5 — bare metal
- Zinc primer / cold zinc (approx. 60 µm) — electrochemical protection layer
- Two-layer epoxy (60–80 µm) — physical barrier
- Two-layer PUR 2K (50–80 µm) — hardness, UV and chemical resistance
This system provides the highest anti-corrosion durability — comparable to hot-dip galvanising, but applicable on-site at the workshop without component disassembly.
Silo trailer components for zinc coating
Frame and chassis: Longitudinal beams, cross members, axle and suspension mounts, kingpin plates.
External components: Access ladder and walkway, lighting supports, handles and locks.
Pneumatic connections: Steel discharge nozzles, hose brackets.
Cold zinc coating — when we apply it
Cold zinc coating applied:
- As primer in the epoxy + PUR 2K system (part of full paint renovation)
- For preventive maintenance of selected chassis components without full renovation
- For coating repair after welding or mechanical damage
For major structural components (frames, beams) we recommend hot-dip galvanising at a galvanising plant (we organise transport and coordination).
Ask for a quote: +48 602 716 551 | biuro@magnumchorula.pl
Related: Sandblasting · Paint renovation · Spitzer service · Feldbinder service