CNC Machined Valve Bodies
Valve bodies combine precise bores, sealing seats, and threaded ports in one part where leak-tight performance is non-negotiable. We machine valve and fitting bodies in stainless, brass, and steel with the bore and seat tolerances that sealing depends on.
What is a CNC machined valve bodies?
A valve body is the main housing of a valve — it contains the flow path, the bore that guides the moving element (spool, ball, or poppet), the seat that the element seals against, and the threaded ports that connect to the system. CNC machining holds the bore roundness, seat finish, and port-thread accuracy that determine whether the valve seals and operates smoothly. These parts are typically pressure- and leak-tested.
Common materials
Corrosion resistance and clean sealing surfaces for fluid and gas valves; 316L for marine and chemical media.
Free-machining, good for low-pressure water, gas, and pneumatic valve and fitting bodies.
For high-pressure hydraulic valve bodies.
Typical tolerance
±0.01 mm on bores & seats
The guide bore and sealing seat are the critical features — held round, straight, and to a fine finish so the sealing element seats reliably.
How we machine them
Machines the body, flow path, ported faces, and external geometry.
Finishes the guide bore to a precise diameter, roundness, and finish for sealing.
Internal passages deburred and the assembled valve pressure/leak tested.
Design tips that lower cost
Define the seat finish and bore roundness
Sealing happens at the seat and bore — specify the surface finish (Ra) and roundness there. These two features, not the outside of the body, decide whether the valve leaks.
Use standard port threads and O-ring glands
Standard thread forms (NPT, BSPP, SAE/ORB) and standard O-ring groove dimensions ensure the body mates to off-the-shelf fittings and seals reliably.
Allow for deburring of internal intersections
Like manifolds, valve bodies have intersecting internal passages. Burrs there cause leaks and contamination — design access for deburring and tell us the cleanliness requirement.
Specify the test pressure and medium
Give us the working and proof pressure and the medium. We pressure- and leak-test to that spec so failures are caught before shipment.
Industries we machine valve bodies for
Valve Bodies — frequently asked
Do you leak-test machined valve bodies?
Yes — we pressure- and leak-test to your specified pressure and medium and can supply the test record. Sealing is the whole point of a valve body, so this is standard.
How fine a bore finish can you achieve for sealing?
We bore and hone guide bores to a fine finish (Ra 0.4 µm and better) with controlled roundness, which is what reliable sealing against a spool, ball, or poppet requires.
Which material should I use for a valve body?
Stainless 316L for corrosion and clean media, brass for low-pressure water/gas and easy machining, and steel for high-pressure hydraulics. Share the medium and pressure and we'll recommend the grade.
Need valve bodies machined?
Upload your drawing — our engineers review it for DFM and send a real quote within 24 hours. No minimum order.
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