CNC Turned Brass C36000 Compression Fitting 1/4 NPT 300PSI Nickel Plated Hex Body

This compression fitting is machined from Brass C36000 (C36000) to ±0.05mm in the critical dimensions, then finished by Nickel plated 5μm. It is produced on CNC turning centres that are dedicated to small and medium volume precision work, so every dimension on the drawing is generated by the machine rather than by hand fitting. Typical users are engineers who have already been let down by a supplier that quoted a tolerance it could not hold, and who need the part to fit the first time without sorting or rework on the assembly line.

• Leak Free Seat Geometry: 45 degree ferrule seat is turned and burnished so tubing deforms evenly and seals on first tightening
• Tapered Thread Control: NPT threads are checked with L1 ring gauges to guarantee engagement depth in the mating port
• Nickel Plated Body: 5μm nickel keeps the fitting clean looking and resists mild chemical splash
• Reusable Joint: The compression design allows repeated disassembly without replacing the body
• Pressure Verified Sampling: A sample from each lot is hydrostatic tested to 1,200 PSI before release

The process route is fixed before metal is cut. Bar stock is verified against the purchase specification and the heat number is logged, then a first article is turned and measured in full. Only after the first article is signed off does the lot run. Critical features on this compression fitting are controlled to ±0.05mm with a process capability target of Cpk 1.33 or better, and the operator checks the feature at a defined frequency with the gauge stated on the control plan. Where the drawing calls for Nickel plated 5μm, the finishing step is carried out in house and the result is measured, not assumed. Sample parts go to the CMM for full dimensional verification, and the recorded results ship with the lot as a first article inspection report in PPAP level 3 format when a customer program requires it.

Questions are handled by engineers rather than by sales staff. Our team reviews each drawing for manufacturability, flags features that would drive cost without adding function, and proposes the tolerance band that actually matters for the assembly. That review is free and is returned within 24 hours together with a quotation. When a part fails in the field, we ask for the sample back, section it if needed and report what the failure mechanism was, because a supplier that cannot explain a failure cannot prevent the next one.

• Machines: 50+ CNC units including Swiss type lathes, 3, 4 and 5 axis machining centres and turn-mill centres from Citizen, Star, Doosan and Mazak.
• Quality lab: CMM, 2D vision measurement, roughness tester, hardness tester, salt spray chamber and spectral analyser for material verification.
• Team: 15+ mechanical engineers covering DFM review, process design, fixture design and failure analysis.
• Capacity: 500,000+ precision turned parts per month with stable output and on time delivery tracking.
• Quality system: ISO 9001:2015 certified, SGS audited, material traceability from mill heat to finished part.
• Export experience: parts shipped to 30+ countries across North America, Europe, Japan, Korea and Southeast Asia.

Pneumatic and low pressure fluid lines, laboratory gas distribution, water treatment skids and instrument air panels.

Parts are degreased, dried and packed so that the surface finish specified above arrives intact. Standard packing is VCI paper or individual PE bag, a partitioned foam tray for form features, and an export grade corrugated carton on a pallet, with the lot number and heat number marked on the outside. Parts are warranted against material and workmanship defects for 12 months from delivery. If a part is found outside the drawing, we replace it at our cost and we pay the return freight for the defective lot. Third party inspection by SGS, BV or TUV can be arranged before shipment at your request, and we work under NDA where drawings are confidential.

Q: Is this fitting rated for gas service? A: The body is rated to 300 PSI working pressure but gas service requires a specific seat material and leak test. Tell us the gas and we will confirm suitable sealing.

Q: Can you supply a lead free version for potable water? A: Yes. We machine the same geometry in lead free Eco Brass for drinking water applications and can supply NSF style material documentation.

Q: What tube tolerance does the compression seat need? A: Tube ovality and hardness matter more than diameter tolerance. Specify a fully annealed tube and deburr the end square before assembly.

Q: Do you test every fitting? A: We test a sampled lot by hydrostatic pressure and leak check each production run. 100 percent testing is available at extra cost.

Q: How do you confirm the Brass C36000 material before it is machined? A: Every bar is checked against its mill certificate with an optical emission spectrometer before it goes to a machine. If the chemistry does not match the grade, the bar is rejected and returned. The certificate for your lot is filed under the heat number and can be sent with the shipment or on request.

Q: What happens if a delivered part measures outside the ±0.05mm tolerance? A: Send the measurement and the lot number. We check the recorded values for that lot, replace the parts at our cost and cover the return freight. Because each critical feature is recorded during production, we can trace the deviation to a tool wear step, a fixture shift or a gauge issue and correct the process before the next lot runs.

Send a 2D drawing, a STEP file or a sample and you will have a manufacturability review and a firm quotation within 24 hours. Trial orders from a single piece are accepted, so the tolerance claim can be checked on your own assembly before a production order is placed.