Precision CNC Turned Stainless Steel 316L Hydraulic Cylinder Piston Rod 45mm Diameter Ra 0.2μm Hard Chrome Plated

This hydraulic cylinder piston rod is machined from Stainless Steel 316L (316L (1.4404)) to ±0.01mm in the critical dimensions, then finished by Hard chrome plating 20μm 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.

• Corrosion Resistant Core: 316L molybdenum bearing austenitic stainless resists chloride attack in wet hydraulic circuits
• Chrome Plated Wear Surface: 20μm hard chrome layer holds Ra 0.2μm and protects the sealing zone from abrasive scoring
• Tight Straightness Control: 0.05mm per 1000mm straightness keeps seal lip contact even and extends gland life
• Rolled Thread Root: Threads are rolled not cut so the root grain flow stays continuous and fatigue strength improves
• Full Traceability: Heat number stamped on each rod and matched to an EN 10204 3.1 mill certificate

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 hydraulic cylinder piston rod are controlled to ±0.01mm 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 Hard chrome plating 20μm 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.

Hydraulic cylinder repair shops, offshore deck equipment, injection molding machine tie-rod cylinders and mobile machinery actuators that operate in humid or washdown environments.

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: Why specify 316L instead of chrome plated 1045 carbon steel? A: Carbon steel with chrome is cost effective indoors but the base metal corrodes once the coating is breached. 316L keeps a corrosion resistant substrate, so a scratch or a worn band does not become a rust initiation site. We recommend 316L rod for washdown, marine and food plant duty.

Q: How do you protect the chrome surface during shipping? A: Every rod is wrapped in VCI paper, sleeved in a rigid PVC tube with end caps, and packed in a wooden case. VCI paper gives 12 months of vapor phase protection for sea freight.

Q: Can you match an existing cylinder drawing? A: Yes. Send a PDF or 2D/3D file with the thread callout, chrome thickness and seal groove detail. Our engineers return a DFM note within 24 hours and a first article inspection report with the first shipment.

Q: What is the smallest order you accept for a first trial? A: One piece is acceptable for a trial order. Production pricing starts at 50 pieces and drops in bands at 200 and 1000 pieces.

Q: How do you confirm the Stainless Steel 316L 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 ±0.01mm 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.