CNC Turned 17-4PH Stainless Steel Turbine Blade Shaft 15mm Diameter HRC 42 Ground

This turbine blade shaft is machined from Stainless Steel 17-4PH (17-4PH H1025) to ±0.008mm in the critical dimensions, then finished by Ground journals Ra 0.2μm. 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.

• High Speed Stability: 0.008mm runout at the journals keeps vibration low at operating speed above 20,000 rpm
• Hardened Journals: H1025 condition at HRC 38-42 resists wear at the bearing contact without a coating
• Blade Seat Flatness: 0.01mm flatness at the blade seat prevents blade cocking, which is a common source of imbalance
• Corrosion Resistance: 17-4PH resists condensate and washdown better than carbon steel shafting
• Balanced Assembly Support: We can mark and supply balance data to help your assembly balance step

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 turbine blade shaft are controlled to ±0.008mm 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 Ground journals Ra 0.2μm, 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.

Micro turbines, turbocharger test rigs, dental air turbine handpieces, high speed spindles and small centrifugal compressors.

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: Can you balance the shaft with the blade fitted? A: We balance the bare shaft to G2.5 and can balance a customer supplied rotor assembly on request. Final trim balance is usually done on your assembly.

Q: Why H1025 rather than H1075? A: H1025 gives a good balance of strength and toughness with better fatigue behaviour in a shaft with stress risers. H1075 is chosen when maximum strength matters more than toughness.

Q: How do you hold 0.008mm runout between centres? A: The shaft is machined between centres, heat treated, then ground between the same centres so the geometric relationship is preserved.

Q: Do you offer magnetic particle inspection? A: Yes, MPI is standard on hardened shafts and the report ships with the lot.

Q: How do you confirm the Stainless Steel 17-4PH 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 ±0.008mm 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.