Still, the gypsy carrier body is the structural link between the windlass shaft and the anchor chain wheel on tugs, workboats, OSVs, dredgers, fishing vessels and coastal cargo ships. It takes the chain pull into the windlass bedplate, so it sees shock load every time the anchor is broken out and cyclic load through every anchor handling cycle. Cast carriers are used on newbuild anchor handling systems and on refit jobs where a worn or cracked carrier is replaced inside a fixed drydocking window, which makes lead time and drawing match more important than unit price.
Specifications
| Parameter | Value |
|---|---|
| Material | aluminium |
| Casting process | Silica sol lost wax investment casting |
| Surface treatment | Shot blast / Epoxy primer / Hot-dip galvanising |
| Documentation | EN 10204 3.1 material certificate; PPAP / FAIR on request |
Material and Process
EN-GJS-600-3 spheroidal graphite cast iron gives 600 MPa minimum tensile strength with 3 percent minimum elongation and a ferritic-pearlitic matrix whose graphite nodules damp the shock loading of anchor break-out. Also, castings are produced by silica sol lost wax investment casting for the fine chain-pocket geometry and near-net shape; the water glass system is used where the carrier is larger and the surface requirement is lighter. Ferritising anneal or normalising is applied to the drawing requirement, then finish machining is done in-house on turning and 4-axis machining centres.
Casting and CNC machining
- Tooling: wax injection die or aluminium pattern built to the approved 3D model.
- Wax injection, assembly and shell building in the silica sol system.
- Dewax, shell firing, melting and pouring with spectrometer control of every heat.
- Shakeout, cut-off, shot blast and gate grind.
- Heat treatment to the specified matrix with test coupons from the same heat.
- CNC: turn the shaft bore and register diameter, mill the chain-pocket form and drive faces, drill and tap the bolt circle.
- Deburr, surface finish, layout inspection and pack.
Tolerances and Inspection
We hold casting dimensions to ISO 8062 DCTG 6 to 7 in the silica sol process and DCTG 8 to 9 in the water glass process, with machining allowance agreed with the buyer at first article. Generally, machined fits, the shaft bore and the register diameter are finished to drawing, commonly +/- 0.02 mm on the bore, with GD&T callouts for concentricity of the chain-pocket form to the bore. Also, inspection is by CMM and articulating arm, Brinell hardness on the machined face and OES spectro verification of chemistry per heat.
NDT and Documentation
Magnetic particle inspection on machined faces and fillet radii, dye penetrant where the drawing calls for it, and ultrasonic testing on heavy sections when specified by the buyer. In general, we can quote radiographic testing for the load-carrying pocket areas. Also, corrosion protection is paint or galvanising to the buyer’s specification for seawater-wetted deck service. Additionally, inspection and NDT are supplied to the buyer’s specified standard and acceptance level; Ningbo Ruican does not supply classification society approval. Overall, documentation covers EN 10204 3.1 material certificate with heat and lot traceability, heat treatment chart, dimensional report, NDT report and PPAP or FAIR on request.
Packaging and Logistics
Still, each carrier is rust-protected, wrapped in VCI paper with desiccant, boxed individually and crated in ISPM 15 heat-treated plywood cases marked with part number, heat number and drawing revision. Additionally, standard dispatch is FOB Ningbo, and air freight is held for refit and repair jobs tied to a fixed docking date. First article parts ship ahead of the production batch so the yard can confirm fit before the vessel arrives.
RFQ Checklist
- Drawing or 3D model (STEP, IGES, DWG) with revision level
- Material and matrix requirement, hardness range
- Chain size, windlass duty, anchor and chain pull
- Machining allowance, datum scheme and critical fits
- NDT method and acceptance level as specified by the buyer
- Coating or painting specification
- Quantity, first article required, target delivery and docking date
- Send drawings to Wendy She – sales@cnsandcasting.com – WhatsApp +86-13777124360
FAQ
Q1: Can you match an existing windlass carrier from a sample instead of a drawing?
A1: Yes. Send the worn sample and we 3D scan it, rebuild the model with the machining allowances and datums agreed with you, then produce a first article for fit check before the batch.
Q2: How fast can a replacement carrier be delivered to a yard during a refit?
A2: Tooling, casting and CNC machining are scheduled as one line, and first article parts ship ahead of the batch. Air freight is used when the docking window is fixed; tell us the docking date and we quote against it.
Q3: What corrosion protection do you recommend for seawater deck service?
A3: Blast to the specified cleanliness, then epoxy primer and topcoat or hot-dip galvanising to the buyer’s paint specification, with the coating record included in the documentation pack.
Q4: Do you supply classification society certificates with the casting?
A4: No. Also, material, inspection and NDT are supplied to the buyer’s specified standard with EN 10204 3.1 certification; Ningbo Ruican does not claim classification society approval.
CTA
Need a quote for Anchor Windlass Gypsy Carrier Body? Send your drawing to sales@cnsandcasting.com or WhatsApp +86 137 7712 4360 for a fast RFQ response from Ningbo Ruican.
