The precision machining capability is a unique strength of Baihui, as it allows us to produce various castings and precision machined parts for automobile makers, components including stainless steel castings, aluminum alloy castings, ductile iron castings, forged parts, and various precision machined parts. We can design, build and maintain tools and dies as required.

Baihui in-house developed butterfly valves and exhaust pipes have been the parts of choice by many local and international machine manufacturers, such as Ford, CNHTC, WEICHAI, OSHKOSH, Volvo, and Daimler-Benz, just to name a few.

Our fully-equipped precision machining workshop has more than 100 machining equipment sets, including the NC lathe, vertical machining center, drilling machine, boring machine, CNC pipe bender, welder, and various hydraulic and mechanical presses. This equipment allows us to produce up to 200,000 exhaust pipes, 250,000 butterfly valves, and 150,000 engine vibration dampening hoses each year. Speak to us for a custom solution.

Precision Machining Solution --- (PM007 Hydraulic Manifold)

Many through holes and mounting holes need to be drilled in the PM007 hydraulic manifold. The hole drilling work needs to done precisely and in the accurate position. Any error that comes during the drilling process may easily result in hole size falling outside the specs, inconsistent results each time a hole is drilled, poor drilling efficiency, and high failure rate. After a careful analysis of the manifold's geometric features, engineers at Baihui have designed a reliable machining process and use high-precision machining centers as well as specialized tools, clamps and drill bits, which allow workers to hold a repeatable tight tolerance for hole size, shape, and position.

Hydraulic manifold is being massively produced.

Technical Requirements
1. Broom finished surface with Ra0.5 roughness
2. Valve seal surface roughness: Ra0.8
3. American standard internal thread: Class 2
4. Tolerance for unspecified dimensions: ±0.127
5. Concentricity for counter bore: ±0.076

Difficulties
Suppose the hydraulic manifold is made of 6061-T6511 aluminum alloy. There are a few factors worth considering that might affect the quality of finished products.
1. A lot of holes should be drilled on all six sides of the aluminum block. Workers need to hold a tight tolerance for hole shapes and position. Valve openings are complex in design which makes clamping a little difficult. The machining process requires frequent changeover of machine tools and drill bits.
2. It is not easy to control the accurate relative position between angled holes as well as intersecting holes.
3. Thread seal surface roughness: Ra0.8. It is not easy to hold surface roughness to that standard.

Clamps, Drill Bits
Pneumatic clamps for multi-hole drilling

Pneumatic clamps for 4-axis machining

Specialized clamps for 4-axis machining

Specially Made Drill Bits