Contents
Overview
The types of shackle used in lifting
The two main types of shackle used in lifting are the dee, or D, shackle and the bow shackle, each named after the shape of its body. Green Pin’s user manual says dees are mainly used on one-leg sling systems and bows mainly on multi-leg systems. Either shape comes with a choice of pin.
In short
- Newer shackle standards usually size a shackle by its working load limit, where older ones went by the diameter of the steel in the body.
- Use a screw pin for temporary connections, and a bolt type pin with a nut and split pin where the shackle stays rigged or the pin could turn.
- A side load cuts the rating, so without the maker’s figures, do not side load a shackle.
- Check the marking and the pin before every use, and take a worn or bent shackle out of service.
On a contract lift, our own appointed person plans the lift and writes the lift plan.
Sources
Where the shackle guidance comes from
Most of the general rules on this page come from COPSULE, the Lifting Equipment Engineers Association (LEEA) code of practice, which our guide to the LEEA Code of Practice explains. The legal duties come from LOLER, and HSE guidance covers the checks users make before each lift.
Some limits vary from one maker to the next, such as how far the rating drops under a side load, how hot a shackle can get, how much wear is allowed and the widest angle between sling legs. Those figures are given as examples, each with its maker’s name beside it.
Check the marking and instructions for the shackles you are actually using, and have the lift planned by a competent person: someone with the training and experience to do the job. On a crane lift that is the appointed person, who plans the lift and controls it under BS 7121.
Shapes
Dee shackles and bow shackles
Every shackle has two ears, the drilled ends of the body that take the pin, and the gap between them is the jaw. A dee shackle, also written D shackle, takes its name from its D-shaped body, and a bow shackle from the rounded bow of its body.
Green Pin recommends its dee shackles for one-leg systems and its bow shackles for one-leg and multi-leg systems. Crosby’s catalogue sells the same two shapes as chain shackles and anchor shackles.
Large and small versions
COPSULE describes large and small versions of both shapes. The small ones have less room inside but a higher rating for their size, which suits fittings such as hook eyes and eyebolts. It also covers the grab shackle, a dee with a countersunk pin so it can pass through a small round hole.
Pins
Shackle pin types
The pin closes the jaw and carries the load across it. COPSULE lists a range of lettered and numbered pin types. The table sets the two body shapes beside the pins you will meet on site.
| Type | What it is | Where it suits |
|---|---|---|
| Dee (D) shackle | A body shaped like the letter D | One-leg systems, in Green Pin’s advice |
| Bow shackle | A body that curves out into a rounded bow | One-leg or multi-leg systems, in Green Pin’s advice. Crosby says multiple legs should not go on the pin |
| Screw pin | A threaded pin with an eye and a collar that screws into one ear | Temporary connections, in Crosby’s advice |
| Bolt type, or safety pin | A bolt held by a nut, with a split pin so the nut cannot work off | Permanent or long-term connections, in Crosby’s advice |
| Round pin | A plain pin with a round head, held by a forelock | Crosby says its round pin shackles must not be side loaded |
| Countersunk pin | A slotted or socket head that sits flush in the ear | Grab shackles, which pass through a small round hole |
When the pin could turn
A screw pin can unscrew if the load or a rope rolls it, and LEEA’s code says to avoid set-ups where that can happen. Where it cannot be avoided, Green Pin recommends a bolt type shackle.
Choosing
How to choose a shackle for a lift
Start with the load each shackle will carry, which can be more than the load’s weight divided by the number of legs. As the legs of a multi-leg sling spread out from vertical, the load in each leg rises, and so does the load in any shackle on that leg.
Choose by the marked working load limit. Our guide to the difference between SWL and WLL explains the figure. Older standards sized shackles by the diameter of the steel, so a shackle’s size alone does not tell you what it can carry.
Matching the shackle to the slings
Two or more sling legs go on the bow. Crosby says multiple sling legs should not be put on the pin, and Crosby and Green Pin both set 120 degrees as the largest included angle, the angle between the legs.
Using
How to use a shackle safely
A shackle is rated for a straight pull from the bow to the pin. Fit it so the body takes the load in a true line along its centre line, with no bending load it was not designed for.
Side loading
Without the maker’s side-load figures, LEEA’s code says to assume a shackle cannot be side loaded. Some makers do publish them. On Crosby’s chart for its screw pin and bolt type shackles, the rating starts to fall at just over 10 degrees from in line. By 45 degrees it is down to 70 per cent, and by 90 degrees it has halved.
Keep the load central on the pin. Where the jaw is wider than the fitting, use a loose spacer on each end of the pin or a shackle with a narrower jaw. Do not weld washers inside the ears or close up the jaw.
Joining two shackles
Crosby shackles can be joined bow to bow or bow to pin and loaded point to point to their working load limit without bending the pin. Crosby allows pin to pin only where the ears of the two shackles do not get in each other’s way. Green Pin’s user manual limits the pair to the lower working load limit of the two. It rules out pin to pin where the ears touch and the pins do not bear properly, and bow to pin where the inner shackle’s body touches the outer one’s ears and they do not bear properly. For any other set-up, ask Green Pin.
Lengthening one sling leg with shackles changes the leg angles. LEEA’s code, in its guidance on chain slings, says the leg at the smaller angle to the vertical takes the larger share of the load, so allow for the change in the lift plan.
Fitting the pin
Screw the pin in finger tight, then nip it up with a small tommy bar so the collar sits on the ear, with the pin reaching the full depth of the threaded ear. If it will not seat, do not use the shackle: refer it to a competent person.
On a bolt type shackle, fit the nut and split pin every time. Ideally the bolt is long enough for the nut to tighten on the inner end of the thread, not against the ears, so the bolt can still turn.
A lost pin is replaced only with one designed for the shackle, because an ordinary bolt may not take the load.
Checks
What to check before using a shackle
HSE’s leaflet Lifting equipment at work points out that thorough examination does not replace checks before use. Clean each shackle and look it over in good light, and check that the body and pin carry the same grade marking. LEEA’s code says to withdraw it from service and refer it to a competent person if it shows any of these faults:
- The rating (SWL or WLL) or identification marking is missing or cannot be read.
- The pin is the wrong one.
- The thread on the pin or in the ear is damaged.
- The body or pin is distorted or worn.
- There are nicks, gouges, cracks or corrosion.
Green Pin rejects a shackle worn by more than 10 per cent of its original diameter. Do not weld or heat a shackle to repair it: LEEA’s code says lifting equipment should not be altered or modified without the approval of the maker or an engineer qualified to approve the change.
Heat
The user manual for the Gunnebo Industries SA shackle, hosted on the KITO Crosby website, allows use at the full working load limit from -40 °C up to 200 °C. Above that the rating drops in steps, and above 400 °C the shackle must not be used. Tell your supplier about extremes of temperature when you order.
Marking and examination
In Great Britain, regulation 7 of LOLER requires lifting accessories such as shackles to be marked with their safe working load and anything else needed to use them safely. Regulation 9 sets when they must be thoroughly examined. Northern Ireland has its own 1999 regulations with the same duties. A European standard for grade 6 dee and bow shackles, BS EN 13889, is covered on our lifting accessory standards page.
LEEA’s code puts the safe working load and grade on the sides of the body, between the ears and the crown, the end of the body opposite the pin. The identification mark and the maker’s trade mark go there too. The code also lists the year of manufacture, and LEEA strongly recommends the grade on the pin as well. Makers can add more: Green Pin also marks the bow diameter in inches and a traceability code. Stamp an identification mark you add in a low-stress area, and use a tag for details that change, such as the examination date.
From our lifts
Each shackle is checked for a readable rating and mark, a pin that matches the body and screws fully home, and no bending or wear. The commonest fault we find is the wrong pin for the shackle. Pins can differ from one maker to another, even on shackles of the same capacity, so a pin can look right and not be. Our pre-use checks pick this up.
The other common problem is a screw pin left finger tight, or a sling that can roll against the pin and unscrew it. Anywhere the shackle stays rigged for a while, or the pin could turn, we use a bolt type shackle with its nut and split pin.
If a pin won’t fit a lug or the jaw is too wide, we change the shackle or fit spacers so the load sits central. We never force it or swap pins, and if neither works the lift is re-planned.
Peter Stephens, Managing Director
Questions
Common questions
What is a shackle?
A shackle is a U-shaped steel link closed by a removable pin. It joins the parts of a lifting set-up, such as a sling to a lifting lug on the load. In Great Britain a shackle counts as a lifting accessory under LOLER, so it must be marked with its safe working load and thoroughly examined.
What is the difference between a dee and a bow shackle?
The difference is the shape of the body: a dee is shaped like the letter D, and a bow curves out into a rounded bow. Green Pin recommends its dees for one-leg systems and its bows for one-leg or multi-leg systems. The table above sets the two shapes beside the pin types you will meet on site.
What is another name for a D shackle?
A D shackle is also written dee shackle, and Green Pin’s user manual calls it a chain shackle. The same manual calls the bow shackle an anchor shackle. Pin names vary between makers as well: Green Pin calls its bolt type pin a safety bolt. Check the shape and pin behind a catalogue name before you order.
How many types of shackle are there?
There are two main shapes of lifting shackle: the dee and the bow. LEEA’s code describes large and small versions of each. It also covers the grab shackle, a dee with a countersunk pin. On top of the shape comes the pin, and the code lists a range of lettered and numbered pin types.
Which type of shackle should not be side loaded?
Crosby says its round pin shackles must not be side loaded at all, though it publishes reduced ratings for side loads on its screw pin and bolt type shackles. Where a maker gives no side-load figures, LEEA’s code says to assume the shackle cannot be side loaded, whatever its shape or pin.
How much weight can a bow shackle hold?
A bow shackle can hold up to the working load limit marked on its body, for a straight pull through the bow and pin. That figure depends on the size and grade of the shackle and on its maker’s rating, so read it from the shackle itself. A side load or high heat lowers it, by amounts each maker sets.
How do I know what size shackle I need?
Pick a shackle whose marked working load limit covers the load it will carry, including the increase from the angle between sling legs. Then check it fits. The pin has to pass through the lifting point and the bow needs room for every sling leg. If the fitting is narrower than the jaw, fit spacers to keep the load central.
Is there a standard shackle size chart?
Each maker publishes its own size chart. Crosby’s chart for its G-209 shackles, for example, lists each nominal size in inches beside its working load limit. Older shackles were sized by the thickness of the body, so read the WLL stamped on the shackle itself before you match it to a chart.
Do shackles need a serial number?
No law requires one. Each shackle must still be identifiable, because its examination report has to give particulars sufficient to identify it. Makers do not have to number each item, and where the maker has not, LEEA’s code makes the user add an identification mark. LEEA also accepts colour coding for a group of shackles kept in one area.
What does the colour of a shackle pin mean?
On Crosby and Green Pin shackles, pin colour is a brand mark. Crosby calls its Red Pin the mark of genuine Crosby quality, and Green Pin lists its green powder-coated pin among its shackle markings. LEEA’s marking guidance, which sets out the marks BS EN 13889 requires, does not mention colour. Read the WLL and grade from the stamped marks.
Get help
Get the shackles and slings for your lift planned
Call us on 0800 008 6096 or email office@synergy-lifting.co.uk. Tell us what the load weighs and send photos of the points you plan to lift from, and we will advise on the shackles and slings.
For a crane lift, see crane hire and contract lifting. For a machine moved across a factory floor, see machine movement.
Get a quote
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Send us the details and we will come back with a quote, usually the same day for a desktop survey.
Or call 0800 008 6096
