U2/U3 360° Anchor Chain Swivel | 14–162 mm

U2/U3 360° Anchor Chain Swivel | 14–162 mm

Product Overview

The U2/U3 anchor chain swivel is a rotating fitting used in a ship anchor-chain connection arrangement to reduce excessive torsional build-up when the anchor and chain change orientation. It is connected between compatible anchor-chain components and carries axial chain tension through its load-bearing eyes while allowing relative rotation around the chain axis. The item is part of the anchoring system and should not be described or selected as general lifting hardware.

The supplied specification covers forged steel or cast steel construction, galvanized or customized surface treatment, and a nominal diameter range of 14 to 162 mm. The detailed parameter table supplied for this page covers 14 to 46 mm. The applicable U2 or U3 grade schedule, material grade, heat treatment, dimensions above 46 mm, testing scope, marking, and classification documentation must be confirmed against the approved drawing and order specification before production.

Quick Specifications

• Product type: 360° anchor chain swivel → rotational fitting for the anchor-end chain arrangement.
• Chain grade: U2 or U3 → grade must be confirmed because proof and breaking loads are grade-specific.
• Nominal diameter: 14–162 mm → detailed supplied dimensions and loads currently cover 14–46 mm.
• Supplied load range for 14–46 mm: 82–837 kN proof load and 116–1170 kN breaking load → neither value is an SWL.
• Construction: forged steel or cast steel → exact material grade, heat treatment, and manufacturing route are to be confirmed.
• Surface treatment: galvanized or customized → coating method and thickness follow the approved order specification.
• Connection matching: select with adjoining links, shackles, eye geometry, and articulation clearance → diameter alone is insufficient.
• Certification and testing: available according to project requirement → confirm class, witness scope, traceability, and test documentation before quotation.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm the required product configuration: single swivel, swivel shackle, swivel forerunner, or complete anchor-chain connection assembly.

Step 2: Confirm nominal chain diameter and chain grade U2 or U3 from the vessel’s approved anchor-chain schedule.

Step 3: Confirm adjoining common links, enlarged links, end links, joining shackles, or anchor shackles, including eye dimensions and articulation clearance.

Step 4: Confirm forged or cast construction, exact steel grade, heat treatment, dimensional tolerance, machining, and non-destructive examination requirement.

Step 5: Confirm galvanizing or other finish, product marking, heat-number traceability, material certificate, load-test record, class society, and witness scope.

Step 6: Provide quantity, vessel type, newbuilding or replacement status, approved drawing or clear photos, delivery destination, and required delivery time.

Structure

Upper connection eye | Central rotating swivel body | Lower connection eye | Rounded load-bearing transitions | Forged or cast steel construction | Galvanized or specified finish

Material, Load Testing & Quality Advantages

• The swivel provides relative rotation in the anchor-end chain arrangement, helping to reduce excessive transfer of twist into the stud-link chain cable.
• Nominal diameter should match the chain schedule, while overall length, width, eye opening, adjacent fitting geometry, and available articulation space must also be checked.
• For forged units, steel grade, forging reduction, heat treatment, machining, dimensional control, mechanical testing, and NDT should follow the approved manufacturing procedure.
• For cast units, cast-steel grade, heat treatment, casting soundness, machining, dimensional control, and NDT should be specified separately from the forged route.
• Rotating and mating surfaces should provide the movement and clearance stated on the approved drawing without excessive play or interference.
• Grade-specific proof and breaking loads must be confirmed. The complete anchor-chain connection is limited by the least suitable component in the load path.
• After galvanizing or coating, dimensions, markings, connection fit, and rotational condition should be checked where coating build-up could affect assembly.
• Inspection documents can include material certificates, dimensional reports, NDT reports, proof-load records, class witness records, product marking, and coating records according to the agreed order scope.

Custom Attributes

• Product Category: Anchor-chain accessory → used in a ship anchoring system, not general lifting service.
• Function: Rotational chain connection → helps reduce excessive torsional build-up in the anchor-end chain arrangement.
• Rotation: 360° designation → permits relative rotation around the chain axis; actual movement depends on load, alignment, wear, corrosion, and connection geometry.
• Nominal Diameter: 14–162 mm → select by the approved stud-link anchor-chain schedule and matching fittings.
• Chain Grade: U2 / U3 → use the correct grade-specific material and load schedule.
• Material: Forged steel or cast steel → exact steel grade and heat-treatment condition are to be confirmed.
• Surface Treatment: Galvanized or customized → coating system, thickness, and acceptance criteria are project-specific.
• Load Basis: Proof Load and Breaking Load → neither value is an SWL or permissible working load.
• Standard Reference: ISO 1704:2022 may apply to stud-link anchor-chain components → actual compliance must be confirmed from the approved design and class requirement.
• Certificate Requirement: Available according to project scope → certificate type and class witnessing must be agreed before production.

How It Works

Anchor changes orientation → Torsional rotation develops in the anchor-end chain components → The swivel permits relative rotation between its connection eyes → Excessive twist transfer into the chain cable is reduced → Axial chain load remains carried through the confirmed connection arrangement

Applications

Ship bow anchoring systems | Outboard anchor-chain shots | Anchor-to-chain connection arrangements | Merchant vessels | Bulk carriers | Tankers | Container ships | General cargo vessels | Tugboats and workboats | Newbuilding and replacement projects

Certifications & Advantages

Certificates and classification inspection can be arranged according to project requirement, approved manufacturing route, material traceability, test procedure, and survey scope.

Certification: CCS, NK, BV, ABS, DNV, LR, KR, IRS, RS, RINA, CRS, Makers Test Certificate.

Drawing & Photos

FAQ

Q1: Are Proof Load and Breaking Load the same as SWL?

A1: No. Proof Load is a specified verification test value, while Breaking Load is a minimum or destructive strength value. Neither is an SWL. Selection must follow the approved chain grade, fitting schedule, and anchoring-system design basis.

Q2: Does 360° mean the swivel rotates freely under full chain tension?

A2: The designation describes the intended rotational function around the chain axis. Actual movement depends on alignment, chain tension, connection geometry, wear, corrosion, and maintenance condition. It should not be promoted as free-spinning under every loaded condition.

Q3: What information is required for quotation?

A3: Confirm product configuration, nominal diameter, U2 or U3 grade, adjoining links and shackles, forged or cast material route, surface treatment, testing and certificate scope, quantity, drawing or photos, delivery destination, and required delivery time.