RIGGING HARDWARE

Shackle

The universal metal connector — a bow or Dee shackle with a pin, rated by working load limit.

INSPECT BEFORE LOAD · NEVER EXCEED WLL

Rope, splices and hardware are only as good as their condition. Inspect before every use and retire on evidence.

Specification

Types	Bow, Dee, anchor, twist
Materials	Galvanised steel, 316 stainless, alloy
Safety factor	5:1 or 6:1 typical
Pin types	Screw, safety bolt, captive
Marking	WLL, size, grade
Common error	Side-loading a Dee shackle

Technical parameters

8 mm galvanised	WLL ≈ 500 kg
10 mm galvanised	WLL ≈ 750 kg
12 mm galvanised	WLL ≈ 1,200 kg
10 mm 316 stainless	WLL ≈ 500 kg
12 mm 316 stainless	WLL ≈ 750 kg
Proof load	≈ 2 × WLL

SelectLoad

Overview

A shackle is a U-shaped body closed by a pin, and it is the most common way to connect two rigging elements. Bow shackles have a wider, rounder body and accept load from several directions; Dee shackles are narrower, stronger for their size, and intended for a straight pull along the axis.

The critical number is the working load limit, or WLL. That is the maximum load the shackle is rated to carry in service, and it is derived from the breaking load by dividing by a safety factor — typically five or six for lifting hardware. A shackle marked with a WLL is not the same as a shackle marked only with a size.

Material matters as much as size. Galvanised steel is strong and cheap and will corrode in salt; 316 stainless resists corrosion well and is weaker for the same dimensions; high-tensile alloys give the highest ratings and demand the most care, because they are less tolerant of being used outside their design direction.

Safety notes

Load a shackle along its axis only. Side loading can reduce capacity by more than half and is the most common shackle failure.
A screw pin can work loose under vibration. Mouse it with wire or use a safety-bolt shackle where the load cycles.
Check for cracks at the bow, wear at the pin and a pin that no longer threads fully. Any of those means the shackle is out of service.

Using it well

Match the shackle to the thimble size so the pin bears evenly across the eye.
Never enlarge a pin hole or re-drill a shackle; that voids the rating and the heat treatment.
Keep a note of the WLL marking on each shackle — the number is the only thing standing between the rating and a guess.

Suited to

ThimblesChainSpliced eyesBlocks

Typical applications

SailingLiftingAnchoring

Figures are typical catalogue values for new equipment, quoted for comparison and planning. They are not a guarantee for any specific product or any specific load. Always work to the manufacturer’s stated working load limit and to the regulations that apply where you sail.

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