Case Study: Engineered High-Pressure Duplex Filtration Upgrade

Client & Industry: Heavy Industrial & Mining (Mill Filtration Upgrade)

Project Focus: Design Verification & System Integration

Software & Tools: SolidWorks 3D Modelling, Component Audit & Pressure Verification

The Challenge

The ball mills are the heartbeat of the Boddington processing plant, and their trunnion bearings rely on a constant supply of clean, high-pressure oil. Any unexpected shutdown means lost production, so the oil filters needed to be serviced while the mill kept running.

Our customer needed a solution that let technicians change filter elements safely at full pressure, give clear proof that the housing was completely isolated and depressurized, and switch over smoothly without causing system surges.

Key Constraints:

Safety & High Pressure: Operating up to 250 bar meant we needed a reliable double block and bleed (DBB) isolation system so filter changes could happen safely without shutting down oil flow.

Tight Space: The new filter setup had to fit inside the existing skid layout while leaving enough overhead room to pull out old elements.

 

The Solution

HWC built a custom 40″ high-pressure duplex filter system around two Pall UH310 Athalon housings, mounted on 2″ Code 62 manifolds and rated for flows up to 600 L/min.

To make operation easy and foolproof, a single handle controls two linked 3-way ball valves. This ensures the inlet and outlet always switch at the same time, so an operator can never accidentally leave a housing half-isolated.

We also added commuter valves to let maintainers fill, vent, and pressurize the standby housing before making a switch, preventing shock or pressure drops in the mill. A dedicated gauge panel—complete with differential pressure gauges and electrical clogging switches—tells the team exactly when a filter needs replacing. Each housing has its own vent valve and gauge, allowing technicians to double-check that pressure is at absolute zero before opening anything.

Key Highlights & Test Results

Working Pressure: Rated for a maximum working pressure of 250 bar and successfully factory-tested up to 350 bar with zero leaks.

Low Pressure Drop: Total pressure drop across a clean assembly at max flow (600 L/min) is just 0.80 bar.

Verified Safe Isolation: Testing confirmed that the single-seat ball valves reliably seal off the standby housing at 350 bar, maintaining a true zero-energy state while the active housing works at full pressure.

Compact Footprint: Fits into a small 401 × 448 mm footprint (1290 mm high) with 268 mm housing centres.

Maintenance Friendly: Requires 1061 mm of clearance above the cover to comfortably lift out the elements.

Recommended Next Steps

1. Finalize Approvals: Send the Revision B Data Sheet Register to the client to confirm valve and manifold ratings and wrap up paperwork.

2. Verify Filter Capacity: Request formal multipass test data from Pall for the UE310AT40H element based on actual site fluid conditions.

3. Site Installation: Install the unit onto the mill skid according to the SolidWorks assembly drawings, following the 13-step changeover and air-bleed procedure

Key Takeaways

For non-stop operations like ball mills, a duplex filter turns a potential shutdown into standard, routine maintenance. Having clear, visible proof that a system is isolated is just as critical as filter performance—it gives maintainers complete peace of mind to work safely. Plus, clear pressure gauges help site teams move away from rigid change schedules and replace filters only when they need it.