The steels that hold 1,050 bar across twelve metres — and get harder every time you touch them.
34CrNiMo6, 40CrNiMoA, 42CrMoA and 00Cr17Ni14Mo2 — the quenched-and-tempered and stainless grades behind our marine fuel-injection work. Deep-drilled on a 12-metre machine envelope — 10 metres production-proven — ground to single-micron fits, heat-treated in-house. In batch production today.
Quenched and tempered means the hardness is decided before you cut.
34CrNiMo6 and 42CrMoA arrive as medium-carbon alloy steels with a purpose: after quenching and tempering they hold strength and fatigue resistance under cyclic pressure. That same hardness is what makes the finish cut expensive — and what makes the roughing allowance a one-way decision:
Leave too little before heat treatment and there is no second chance; too much, and the finish cut has to remove hardened metal
Distortion after quenching is a fact of the process, not a defect. Finishing has to sit after heat treatment in the routing, not before it
00Cr17Ni14Mo2 (316L-class) is tough, gummy and a poor conductor of heat; a dull edge hardens the surface instead of cutting it
The rail family runs to 10 metres in production, on a 12-metre machine envelope, with walls thick enough to carry 1,050 bar. Chip evacuation and straightness over that length are process problems, not machine problems
Plunger and barrel pairs hold clearance in the 1.2–1.8 μm band. At that scale, surface finish and roundness are the fit
1,050 bar working pressure, tested to 1,450 bar with a 15-minute hold. A pressure-test record ships with the part
| Parameter | Capability |
|---|---|
| Grades in production | 34CrNiMo6 · 40CrNiMoA · 42CrMoA · 00Cr17Ni14Mo2 (316L-class stainless); castings and forgings to print |
| Turning | To Ø800 × 8,000 mm; shop envelope Ø1,000 × 10,000 mm |
| Deep-hole drilling | BTA Ø20–360 mm; 12 m machine envelope, 10 m production-proven |
| Grinding | Tolerances to 0.005 mm; finishes to Ra 0.4 μm |
| Matched fits | Plunger-barrel clearance held in the 1.2–1.8 μm band |
| Heat treatment (in-house) | Vacuum hardening to 1,250°C, carburizing, nitriding, induction hardening |
| Coating & finishing (in-house) | Hard chrome, electroless nickel, shot peening, laser cladding |
| Inspection | 2× Hexagon GLOBAL S CMM; roughness tester to 0.002 μm; roundness tester |
| Documentation | Mill certificate with heat-number traceability + dimensional report with every order |
These grades are not a capability statement — they are the daily production mix:
Fuel, servo, servo-oil and supply pipes for low-speed two-stroke marine engines; rails to 10 m in production (12 m machine envelope); 1,050 bar working / 1,450 bar tested; the pressure-test record ships with the part
Batch production; precision ground to Ra 0.4 μm
Matched-pair clearance held in the 1.2–1.8 μm band
Batch production; sealing faces to Ra 0.4 μm, flatness to 0.005 mm
Rough, heat-treat, finish. Get the order wrong and no amount of machine capability recovers it
Long bores are drilled and honed first; the ground surfaces come after, so the finish is not carried through a second thermal cycle
Every heavy cut leaves residual stress behind it. Between operations is where we remove it
Feed and speed windows for quenched material are learned, not looked up. Too conservative and the surface work-hardens; too aggressive and the edge goes
They sit under the same roof as the cutting — no subcontractor queue inside your lead time
Difficult alloys demand proof at both ends — what the mill delivered, and what we shipped:
The mill origin follows your part through every operation to the inspection report
Incoming verification by SPECTROMAXx 08 optical emission spectrometer; no certificate is taken at face value
Mill certs plus our inspection reports, in the documentation package your quality team expects
The 1,450 bar / 15-minute hold record ships with the part
Yes — but the routing matters more than the cutting. We plan the allowance so the finish operation sits after heat treatment, then grind and turn the hardened material with tooling chosen for it.
Yes. Vacuum hardening to 1,250°C, carburizing, nitriding and induction hardening are all in-house, on the same quality system as the machining — no subcontractor queue inside your lead time.
By grinding the pair together and verifying roundness and surface finish as part of the fit — at that scale, geometry and finish are the clearance. Every pair ships with a dimensional report.
A 12-metre machine envelope, with 10 metres production-proven. Bores run from Ø20 to Ø360 mm, and the pressure-test record ships with the part.
From one piece — one drawing is enough. Prototypes and production runs share the same floor, machines and process documentation.
Attach the drawing and the grade; an engineer replies within 24 hours with manufacturability feedback. NDA welcome.
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