Specifications
| Item | Specification |
|---|---|
| Material | AISI 316L (UNS S31603), duplex 2205 (UNS S32205), super-duplex 2507 (UNS S32750), nickel-aluminium-bronze-equivalent stainless UNS S32550 (ASTM A995 Gr. 5A) |
| Process | Silica sol lost wax investment casting; water glass lost wax for sections above 300 mm |
| Dimensional tolerance | ISO 8062 CT4–CT6 (silica sol); CT6–CT8 (water glass) |
| Surface finish | Ra 3.2–6.3 µm as cast; Ra 1.6 µm on machined pocket flanks and bores |
| Machining | CNC machining of chain pockets, bore, keyway, snap-ring groove and bolt circle |
| Weight range | 8–220 kg per piece |
| Inspection & certificates | EN 10204 3.1 mill certificate, positive material identification, magnetic-particle, ultrasonic and dye penetrant testing, dimensional report, heat-lot traceability |
Key features
- Cast chain pockets reproduce stud-link and studless chain pitch in one piece, removing weld build-up and the heat-affected zones that initiate crevice corrosion on fabricated wildcats.
- Duplex 2205 and super-duplex 2507 deliver roughly twice the yield strength of 316L, so pocket walls stay thin and the rotating mass drops.
- Nickel-aluminium-bronze-equivalent stainless gives the galling and cavitation resistance needed where the chain runs under high line pull.
- Silica sol casting holds ISO 8062 CT4–CT6, so pocket-to-pocket pitch variation stays inside the chain manufacturer’s tolerance band.
- CNC finish machining of the bore, keyway and bolt circle makes the lifter drop-in ready for the windlass shaft and brake band.
- Pickling and passivation per ASTM A967 removes free iron and restores the chromium-oxide film before the part ever sees salt spray.
Applications
- Anchor handling and mooring windlasses on harbour and terminal tugs
- Moreover, Platform supply vessels and offshore support vessels working dynamic positioning
- Anchor recovery gear on dredgers and trailing suction hopper vessels
- Coastal ferries and ro-ro passenger vessels with high-frequency anchoring cycles
- Naval and patrol vessels needing low-magnetic-signature deck machinery
- Large private and charter yacht windlass drives up to 100 mm chain
Quality and compliance
Ningbo Ruican runs its investment casting and CNC machining under an IATF 16949 certified quality system with ISO 9001 as the base layer. Every cable lifter ships with an EN 10204 3.1 mill certificate tied to a single heat lot, so the chemical analysis and mechanical properties can be traced back to the melt. Non-destructive testing is specified per drawing: magnetic-particle inspection on pocket roots and section changes, ultrasonic testing on hub and rim sections above 40 mm, and dye penetrant testing on all austenitic and duplex surfaces after finish machining.
Where the lifter forms part of a seawater-wetted assembly, hydrostatic testing of the mating housing can be carried out in house. Classification-society witness of mechanical testing and NDT (ABS, DNV, LR, BV, ClassNK or RINA) is not held as a standing works approval; it can be arranged on request per project, with the surveyor’s attendance and documentation scope agreed at order stage.
FAQs
What information do you need to quote an anchor windlass cable lifter?
A drawing with chain size and type, pocket count, bore and keyway dimensions, bolt circle, and the required material. If you only have a sample, we reverse engineer it by 3D scanning, then issue a drawing for your approval before tooling.
Which material is best for a windlass cable lifter in warm seawater?
Moreover, duplex 2205 is the usual first choice for its combination of strength and pitting resistance. For tropical service, splash zones or high line pull, super-duplex 2507 or the NAB-equivalent stainless grade gives a higher PREN and better galling resistance against the chain.
Can you cast the chain pockets to net shape?
Pockets are cast close to net shape and then CNC finish machined on the load-bearing flanks. This keeps the as-cast skin where it helps fatigue life while holding the pitch accuracy the chain needs.
Do you supply PPAP or first article inspection documentation?
Yes. Dimensional reports, material certificates and NDT records are provided as standard, and PPAP or FAIR packages can be issued to your format when the project requires it.
What is the tooling lead time for a new cable lifter?
Tooling for a new design is typically completed in four to six weeks, with sample parts following shortly after. Repeat orders against existing tooling ship faster because the pattern set is already proven.
