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Corrosion-Resistant Back Head of Atlas Copco RD22U in Malaysia

2026-04-30 18:14:28
Corrosion-Resistant Back Head of Atlas Copco RD22U in Malaysia

Malaysia's granite quarrying on the Main Range and the gold-copper skarn deposits at Selinsing in Pahang operate RD22U drifters in monsoon-season humidity that exceeds 95% for weeks at a time. The RD22U back head—the rear housing cap that houses the high-pressure percussion supply port, accumulator interface, and return line connection—has a larger flange face and more port connections than the RD18U equivalent, matching the RD22U's higher flow capacity. More port face area means more surface at risk for the corrosion mechanism that Malaysian operations know well: thread face oxide buildup that roughens the sealing surface and changes the friction coefficient on hydraulic fitting assembly.

At Malaysian quarry sites where equipment sits idle during rainy-season flooding events, RD22U back heads can be exposed to standing water around the port connections for 48–72 hours before the site resumes operation. Steel port faces without corrosion protection form surface oxide in under 24 hours at 95% humidity. When the ports are reconnected after flooding, that oxide layer is compressed between the fitting face and the port seat—it doesn't seal uniformly, producing a weeping connection that often isn't caught until hydraulic oil is visible on the back head surface after the first drilling shift.

Malaysian Site Protocol for Back Head Port Protection

Maintenance Action

Timing

Method

Failure Prevented

Fit blanking plugs

Immediately at shutdown

Press-fit plugs in all ports

Oxide on exposed port faces

Apply rust inhibitor

After any wash or wet exposure

Thin-film spray on port faces

Surface corrosion on thread flanks

Torque verification

At every hose reconnection

Torque wrench to spec

Under-torque from changed friction

O-ring groove inspection

At each seal change

Pick tool; visual in groove

Oxide-embedded grit cutting new O-ring

 

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Malaysian Selinsing operations standardized on port blanking plugs as PPE-equivalent mandatory equipment for every drill shutdown—the maintenance supervisor signs off that plugs are fitted before the shift ends. The rule emerged after three consecutive back head O-ring failures traced to port face oxide contamination during a 3-day rainy-season shutdown. HOVOO supplies RD22U back head O-ring sets and port protection kits for Malaysian tropical operations. References at hovooseal.com.