The valve body blank is the forged or cast pressure shell of an LPG and industrial gas cylinder valve, forming the neck thread, the outlet thread, the seat bore and the handwheel or regulator interface. Ningbo Ruican supplies investment cast blanks in brass, bronze and stainless, machined to your gauge drawings, solving the supply problems buyers face with inconsistent seat concentricity, porosity at the neck thread root and batches that fail leak testing at the filling plant.
Specifications
| Parameter | Specification |
|---|---|
| Casting process | Silica sol lost wax investment casting; hot chamber and gravity die casting options for high volume brass |
| Material options | C37700 and C85700 forging brass; C83600 and C84400 bronze; ASTM A351 CF8M and CF8 stainless; ASTM A216 WCB steel on request |
| Dimensional tolerance (ISO 8062-3 CT grade) | CT5 to CT6 as cast; neck and outlet threads machined to gauge; seat bore concentricity within 0.05 mm |
| Machining | CNC turning of neck and outlet threads to NGT, NPT, BSP or W standards, seat bore boring and reaming, facing of handwheel and regulator seats |
| Surface finish (Ra) | As-cast Ra 3.2-6.3 um; machined sealing faces and seat bore Ra 1.6 um; nickel or chrome plating and passivation available |
| Pressure testing | Hydrostatic shell test and 100 percent pneumatic leak test under water to customer or filling plant procedure; batch records retained |
| Weight range | 0.08 kg to 1.6 kg per blank |
| Typical lead time | 20 to 30 days for tooling and samples; 25 to 35 days for production after sample approval |
Scope and options
Key features
- Neck and outlet threads machined on CNC lathes to the customer’s gauge standard, so the blank torques into the cylinder collar and accepts the regulator without rework.
- Seat bore bored concentric with the neck thread within 0.05 mm, keeping the shut-off disc square to its seat through the full service life.
- Low porosity pressure shell achieved by feeding simulation on the heavy neck section, with radiography or pressure decay testing available on a defined sampling plan.
- Brass, bronze and stainless routes all available from the same tooling family, letting you cover domestic, industrial and marine markets on one design.
- Outlet, pressure relief and fill limiter ports cast as bosses and machined to drawing, cutting secondary drilling and assembly operations.
- Moreover, Plating, passivation and surface protection applied in controlled batches, with coating thickness verified and reported.
Applications
- LPG cylinder valves for domestic 5 kg to 15 kg cooking gas cylinders.
- Industrial and commercial LPG cylinder valves for forklift, catering and heating cylinders.
- Autogas and vehicle LPG tank valves including fill limit and service valve bodies.
- Industrial gas cylinder valves for oxygen, nitrogen, argon and carbon dioxide service.
- Refrigerant, ammonia and specialty gas cylinder valve bodies for chemical plants.
- Marine and camping gas cylinder valves in brass or stainless for corrosive atmospheres.
Quality & compliance
Inspection and documentation
LPG cylinder valve body blanks are manufactured under IATF 16949 process control with gauge-level verification of every thread and seat bore, because these features decide whether the valve passes filling plant acceptance. EN 10204 3.1 material certification is issued as standard with 3.2 third party witnessed certification available, and brass heats are supported by spectrographic analysis and dezincification resistance data where specified. Still, every production blank is pressure tested, and 100 percent pneumatic leak testing under water is available to your procedure. Dye penetrant inspection per ASTM E165, radiography of the neck section and dimensional reports are supplied on request, together with PPAP and first article inspection. Ningbo Ruican does not hold or claim EN ISO 15995, EN 13152, TPED or CE certification as a company certificate; we supply to the customer’s specified standard and provide the test evidence to support your own type approval.
FAQ
Which thread standards can you machine?
We machine neck and outlet threads to NGT, NPT, NPSM, BSP, BS 341, W and other national cylinder standards, verified with the appropriate go and no-go gauges. Send your gauge drawing or standard reference and we will confirm the tooling and inspection route.
Do you test every valve body blank?
Generally, hydrostatic shell testing is performed to your written procedure. In general, we offer 100 percent pneumatic leak testing under water with recorded dwell time and batch traceability. Additionally, sampling plans for radiography and dye penetrant inspection can be set to your AQL.
Brass, bronze or stainless, which do you recommend?
C37700 and C85700 brass cover most domestic and industrial LPG valves, C83600 bronze suits marine and corrosive service, and CF8M stainless is chosen for specialty and high purity gases. In general, our team matches material to your gas, market and regulatory requirement.
Can you supply blanks for us to finish machine?
Yes. We regularly ship rough machined blanks with the threads finish turned and the seat bore semi-finished, leaving defined stock for your final operations. Machining stock, thread class and seat pre-bore diameter are agreed on the drawing before tooling is cut. We can also deliver fully machined bodies, leak tested and cleaned, ready for your assembly line.
Can you help with type approval documentation?
We supply material certification, dimensional reports, pressure and leak test records, NDT reports and PPAP to support your type approval submission. We do not hold the product certificate ourselves, so your notified body reviews the evidence package we generate to your specification.
CTA
Send your LPG cylinder valve body blank drawing, thread standard, material and yearly volume to Ningbo Ruican for a competitive quotation and a sample plan. Contact Wendy She at sales@cnsandcasting.com or WhatsApp +86-13777124360, or visit cnsandcasting.com for more gas valve component work.
