FAQ stop chains
On this page you will find frequently asked questions from our customers about sling chains. If you have a question that is not answered here, please do not hesitate to ask us. We will be happy to answer them for you in person or by mail.
Your questions:
- What are sling chains?
- What are stop shortening hooks?
- Which grades does Dolezych have in its product range?
- Which chain systems can be supplied?
- What is the difference between the individual grades?
- How do I identify the different grades?
- What is the angle of inclination and how is it measured?
- What is the angle of spread?
- What is the useful length of a sling chain?
- Why do the hooks always have to point outwards?
- Can I also use a multi-strand sling chain in a single strand?
- What documents do I receive when I order a sling chain from Dolezych?
- How must the sling chain be marked?
- What information can I find on the chain’s load capacity tag?
- What information can I find on the inspection sticker?
- What is the load capacity of the sling chain if the load capacity tag is lost?
- How often do I need to have my sling chains and related components inspected?
- When is a sling chain ready for discard?
- May sling chains of grade 8, 10 and 12 be used in pickling plants and hot-dip galvanizing plants?
- At what temperatures may the sling chains be used?
- Which regulations are fundamental for the use of sling chains?
- Where can I find the operating instructions for Dolezych sling chains?
Our answers:
What are sling chains?
Explanation: Lifting chains of GK8 and GK10 are among the most important lifting gear. They are used in a wide variety of applications to lift heavy loads or goods (e.g. in construction or industry).
What are stop shortening hooks?
Explanation: Stop shortening hooks are always used in conjunction with chain slings. The variably applicable shortening hooks with safety device save components and shorten sling and lashing chains directly in the working area.
Which grades does Dolezych have in its product range?
You can obtain sling chains from Dolezych in grades 6, 8, 10 and 12.
- Grade 8: DoKett – sling chains
- Grade 10: DoKettPlus – sling chains, DoComfort – sling chains
- Grade 12: DoComfortMax sling chains
- Grade 6: DoKett – Stainless steel sling chains
Other grades on request.
Which chain systems can be supplied?
- Modular system
- Assembly with chain connecting links (grade 6, 8, 10)
- Mounting in clevis system (grade 6, 10, 12)
- Welding system
Please ask your Dolezych team for chain slings for special applications!
What is the difference between the individual grades?
The difference between the individual grades of sling chains is that the load capacity increases with increasing grade while the material thickness remains the same.
How do I identify the different grades?
The quality class of a chain as well as its components (hooks, connecting links, shorteners, etc.) can be recognised by the quality class marks 8, 10 and 12.
What is the angle of inclination and how is it measured?
In the tables on the information pages on sling chains you will often find two angles. These angle values refer to the angle of inclination. The angle of inclination is determined by the degrees between an imaginary vertical straight line and the chain itself. The load capacity of a chain strand changes depending on the respective angle of inclination of a slung load: The greater the angle of inclination, the lower the load capacity. Angles of inclination exceeding 60° are not permitted! If different angles of inclination occur in the case of multiple-strand sling chains (asymmetrical load distribution), only the load-bearing capacity of the strand with the greatest angle of inclination may be taken as a basis. In individual cases, shortening hooks and compensating rockers can be helpful here.
What is the angle of spread?
In contrast to the angle of inclination, the angle of spread measures the angle between two chain strands (maximum 120°).
What is the useful length of a sling chain?
The useful length L describes the length of a sling chain plus its fittings, as shown in the following diagram.
Why do the hooks always have to point outwards?
The hook openings must always face outwards in order to avoid unintentional unhooking of the load.
Can I also use a multi-strand sling chain in a single strand?
Yes, the chain strands that are not under load are hung back in the suspension link/set. In this case, the permissible WLL is reduced to that of a single strand chain.
What documents do I receive when I order a sling chain from Dolezych?
Factory certificate DIN EN 10204-2.1 and declaration of conformity are automatically included in the scope of delivery. A chain file card is issued in the course of our annual UVV inspection.
Further documents on request.
How must the sling chain be marked?
A sling chain is always marked with a load capacity tag and by us additionally with a UVV inspection sticker.
What information can I find on the chain’s load capacity tag?
- Load capacity in t for
- 1 strand under angle of inclination 0°.
- 2-/3-/4-strand under angle of inclination 0°-45° / 45°-60°.
- Number of strands
- Nominal thickness of the chain in mm
- Manufacturer date (month/year)
- Manufacturer’s mark Dolezych (DD)
- CE mark
What information can I find on the inspection sticker?
- Date of next UVV inspection (month/year)
What is the load capacity of the sling chain if the load capacity tag is lost?
In this case, the sling chain is downgraded to quality class 2 (DIN 685) and must be inspected promptly by an expert. Use our Dolezych inspection service for this purpose.
How often do I need to have my sling chains and related components inspected?
In principle, a sling chain must be inspected by an expert before it is put into operation for the first time. In addition, DGUV 109-017 prescribes regular inspections at intervals of no more than one year by an expert for load handling attachments. However, depending on the conditions of use, tests may be required at intervals shorter than one year. This applies, for example, in the case of particularly frequent use, increased wear, corrosion or heat exposure or if increased susceptibility to faults is to be expected. Round steel link chains used as slings must be subjected to a special inspection for freedom from cracks at intervals of no more than three years (or no more than two years in Austria). We carry out this crack testing with an electromagnetic crack tester in our laboratory or with our test van on your premises.
Are you interested in our testing service? You can find important information here.
When is a sling chain ready for discard?
- Cracks or deformations of a chain link
- Decrease of the average thickness of the links at any point by more than 10% of the nominal thickness.
- elongation of the outer nominal dimension L by more than 3% (or an inner elongation by 5%)
- widening of the hook mouth by more than 10% or other deformations
- Wear of the hook base by more than 5%
- Wear of the suspension and end links (material thickness in mm) by more than 10%.
- Missing or illegible identification tag (reduce load capacity according to grade 2)
- Discolouration due to heat influence
- Fracture of a chain link
May sling chains of grade 8, 10 and 12 be used in pickling plants and hot-dip galvanizing plants?
No, the use is in accordance with the BG rules and DIN standards are not permitted.
At what temperatures may the sling chains be used?
The following table shows the load capacity per grade as a function of temperature.
| Temperature | |||||||||||
| -60° | -40° | -30° | 0° | +200° | +250° | +300° | +350° | +380° | +400° | ||
| GK 8 | DoKett | 100% | 90% | 75% | |||||||
| GK 10 | DoComfort | 100% | 90% | 75% | |||||||
| DoKettPlus | 100% | 90% | 75% | ||||||||
| GK 12 | DoComfortMax | 100% | 90% | 75% | |||||||
| GK 6 | DoKett stainless steel | 100% | 75% | ||||||||
| Temperature | ||||||||
| -20° | -10° | 0° to +100° | +150° | +200° | +250° | |||
| GK 2 | 50% | 75% | 100% | 75% | +50° | +30° | ||
| Temperature | ||||||||
| -40° | +300° | +400° | +475° | |||||
| GK 4 | 100% | 75% | 50% | |||||
Which regulations are fundamental for the use of sling chains?
The applicable regulations and technical rules for sling chains can be found in detail in the following works:
- Chain slings grade 8 / 10 / 12 DIN EN 818-2 / DIN EN 818-4 / PAS 1061
- Stop chain quality class 6 (stainless steel) similar to DIN 5688-1
- DIN 685 Part 5 Tested round steel link chains, use
- DIN EN 818-6 Chain slings, instructions for use and maintenance
- DGUV 109-004 Safety rules for round steel link chains as slings in hot dip galvanizing plants
- DGUV 109-017, Load lifting devices in hoist operation
- DGUV 209-013 Safety training letter for slingers
- 2006-42-EC Directive for machinery and its amendments
- DIN EN 1677-1-4 Components for slings – Safety
If necessary, additional special regulations must be observed, e.g. for the transport of dangerous goods.
Where can I find the operating instructions for Dolezych sling chains?
You can download the operating instructions for sling chains here . You will find a general overview of our operating manuals here.
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