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FAQ

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General

JDT distributes lifting chains in grade 8, 10 and 12 as product group NORM8, ENORM and MAXNORM. The grade refers to the nominal strength of the chain. Grade 8 chains have a calculated strength of 800 MPa, grade 10 of 1000MPa and grade 12 slings of 1200MPa. 
This results in an increase in load capacity of 50% between Grade 8 and Grade 12. For the same load capacity, the nominal size of the chain can usually be reduced by one nominal size. This significantly reduces the weight of a chain hanger.

Our product range distinguishes 3 sectors : Industry, Mining & Robotics.

In the industrial sector, our product range includes: chains, chain slings, hooks, connectors, as well as attachment points and  swivels.

In the mining sector, our product range includes: chains, locks and accessories (flights, sprockets, extractors and chain gauges).

In the Robotics sector, we offer cross-industry automation solutions. From consulting, concept development to commissioning, cross-system from a single source.

Chain sling: Round steel chain installed in chain hangers and used for slinging loads. Chain slings always have a pitch of 3 x nominal chain diameter. 
Hoist chain: Round steel chain that is permanently installed in the hoist and used to lift a load.
[SOURCE: DIN 685-1:1981-11, term 3.1.1]

 

Lashing chains are used to secure loads.  They consist of different components to secure a load from slipping during transport. Lifting chains are installed in chain slings and used to attach loads.

 

Special sling chains used to secure sheet piling during installation and removal of the walls.

Lifting chains

The individual components of a welded chain sling are captively connected to each other. In the case of a modular chain sling, the individual components are connected to each other by means of a bolt system. This system is detachable and individual components can be easily replaced.

 

 

JDTcan supply chains in modular system (assembly with chain connecting links or clevis system) and in welding system.

 

 

In order to reduce abrasive wear in blasting plants, JDT can offer sling chains that are precisely tailored to the application.

 

 

DIN EN 818-6 defines an edge as a sharp edge if its radius is smaller than 2 x diameter chain (nominal dimension). DGUV Rule 109 -017 describes a sharp edge when a radius is smaller than 1x nominal dimension of the chain.

 

Chain slings are significantly more robust. They are less sensitive to damage. Can be adjusted in length.

The angle of inclination can generally be described as an angle that indicates the gradient of a straight line or plane. The inclination angle is measured to the perpendicular of the chain strand.

 

The bigger the angle of inclination, the higher the force that is applied. Angles of inclination greater than 60° are not permissible due to the forces that occur.

 

Before each use, the shackles should be inspected for the following characteristics: Markings on the shackle must be legible. Shackle and pin must not have cracks or similar material defects. Shackle and pin must be of the same brand and type. The load must be evenly distributed over the entire pin.

 

The useful length describes the length of a sling chain plus its fittings.

A sling chain is always marked with a load capacity tag and can also be provided with a UVV inspection sticker

 

 

JDT NORM8 and ENORM sling chains of grade 8 and 10 can be used from -40° to +400°C.
JDT MaxNorm sling chains grade 12 can be used from -60° to +300°C.

 

NORM 8 is available in the following finishes: black painted, Telicoat (silver-gray organ. color coating light corrosion protection), galvanized, COR92 (silver-gray organ. coating with high corrosion protection), hot-dip galvanized, sherardizing.
ENORM is available in powder coated or COR92 for corrosion protection.
MAXNORM: powder coated.

 

Hooks must point outward to counteract unintentional unhooking and to reduce widening of the hook .

 

In the case of asymmetrical load distribution, in extreme cases only one chain leg could carry the entire load. This must be taken into account when using chain slings.    
In the case of asymmetrical load distribution, the load capacities for the 2- to 4-legs sling types are the same as for 1-leg. Alternatively, the design can be carried out by a competent person.

 

When using the spreader plate, all four strands can be considered as load-bearing due to the optimized load distribution. This increases the load-bearing capacity of the entire suspension system.

 

 

In principle, only load hooks may be used that are equipped or designed in such a way that unintentional unhooking of the load handling attachment, the sling or the load is prevented. This must also exclude any incorrect loading of the load hook. This can be achieved by a safety device (e.g. hook mouth safety device or safety flap) or the hook shape.
Load hooks without a safety device may only be used in exceptional cases and in consideration of the risk assessment and written operating instructions.

 

Yes. After consultation with our design department, we can provide you with an individual solution proposal.

 

Chain slings are marked with a tag indicating the grade and load capacity of the chain slings at different angles of inclination, as well as by individual marking on the chain. Grade 8 has an 8-sided tag, grade 10 has a 10-sided tag. There is no standardized representation for grade 12, at JDT it is worked out as a chain gauge.

 

Yes, please contact us. We will be happy to submit an individual solution proposal for your application.

 

Attachment points

Conventional eyebolts according to DIN 580 are rigid and may only be loaded axially or up to max. 45° lateral tension. Loading in the transverse direction is not permitted, but is possible and dangerous if the eyebolt is misaligned. Likewise, eyebolts must not be used for turning and rotating. Rotatable anchor points, on the other hand, can be adjusted in the direction of tension, which rules out impermissible transverse loads. Furthermore, rotatable anchor points with additional ball bearings are also suitable for rotating and turning.

 

JDT attachment points are always stamped with the load capacity in the most unfavorable application case, i.e. with the THEIPA Point with the load capacity under 90° and with the Flat Point with the load capacity under 0°.

 

 

Attachment points are used to create a possibility on a load to lift this load by means of a sling or load handling device.

 

The advantages of the THEIPA Point compared to other attachment points are, among others, its high load capacity with a compact design as well as the pear-shaped link with pinch marks, which prevent the link from latching. Due to the additional bearing, the THEIPA Point is also suitable for jerk-free turning and rotating under load. In addition to the thread designs available as standard, other thread types and lengths are also possible, even in small quantities.

 

 

THEIPA Points are stamped on the body with the load capacity under 90° and marked with traceability code, CE and manufacturer and on the bearing surface with thread size and length .

 

The THEIPA Point is a ball-bearing sling swivel, which is also suitable for rotating and turning under load. The Flat Point is a rotating anchor point with movable load bar, with replaceable screw and low overall height. Rotating and turning under load is not permitted.

 

 

In addition to the thread designs available as standard, intermediate sizes and special threads as well as deviating thread lengths are also available on request.

 

Attachment points may also be used as lashing points. However, they may not subsequently be used for lifting.

 

JDT offers attachment points in various mounting designs, e.g. for bolting on by means of external or internal thread, with one or two screws or as a variant for welding onto flat surfaces or for edge attachment.

 

The screws of the flat point may be replaced, provided they comply with strength class 10.9 and are crack-tested. Can also be ordered from JDT. The operating instructions must be observed.

 

Lashing equipment

Load security means that the load is secured during transport against the physical forces of movement that occur. According to § 22 paragraph 1 StVO load, the load including the devices for load securing as well as loading equipment must be stowed and secured in such a way that they cannot slip over, roll back and forth, fall down or generate avoidable noise even during emergency braking or sudden evasive action.

 

There are two variants of load securing. On the one hand, there is friction-locked load securing, in which the load is lashed to the floor (tie-down lashing). The other is form-fit load securing. In this case, the load is lashed directly to the lashing points provided (direct lashing / diagonal lashing).

 

On the one hand, there is friction-locked lashing, in which the load is lashed down to the ground. The other is form-fit lashing. In this case, the load is lashed directly to the lashing points provided (direct lashing / diagonal lashing). 

 

Yes, there are protective tubes which can be inserted in different sizes (adapted to the chain). Or edge protectors made of plastic which are positioned between the chain and the load surface.

 

With JDT ratchet tensioners, the anti-rotation lock is easy to replace. For other makes, contact the manufacturer.

 

QM documentation

According to DGUV Rule 109-017, lifting gear must be inspected at least once a year by a competent person. Depending on the operational risk analysis, this period can also be shorter.

 

According to DGUV rule 109-017: "Round steel chains used as slings must be subjected to a non-destructive test for freedom from cracks at intervals of no more than three years, in the case of port work at intervals of no more than one year (see also DIN 685-5 and § 27 of DGUV regulation 36 and 37 "Port work"). a freedom from cracks test on slings chains must take place at least every 3 years. "

 

according to DGUV regulation 109-017:
-deformation or breakage of a chain link
-mechanical damage (e.g. cracks, notches) or corrosion scars affecting the load-bearing capacity
-damage due to temperature influences (e.g. discoloration)
-decrease of the averaged link thickness at any point by more than 10 % of the nominal thickness.
-lengthening of the outer nominal dimension by more than 3 %.

 

according to DGUV regulation 109-017:
-defects, cracks and corrosion - for inspection of the hook shank, the hook suspension must be dismantled if necessary.
-remaining deformation of the hook body, e.g. widening of the hook mouth by more than 10 % or twisting
-wear of the hook body, e.g. the depth of wear at the lowest point of the hook base must not exceed 5 % of the nominal dimension of the web height
-sharp grooves and edges or other surface defects on wear surfaces; they must merge smoothly into adjacent surfaces
-defects in the anti-rotation device of the nut
-malfunction, wear of the hook jaw locking device

 

Test certificate and operating instructions (for products according to EU Machinery Directive) are part of the delivery. JDT customers can also conveniently retrieve the documents via the JDT customer portal.

 

The customer must archive the following documents for each sling: the test certificate and documentation of the last tests performed. For products that fall under the EU Machinery Directive 2006/42/EC, the operating instructions and the EU Declaration of Conformity must also be archived. The test certificate, operating instructions and declaration of conformity must be archived for the entire service life of the slings.

 

Chain slings are provided by the manufacturer with a tag indicating the load capacity and nominal size of the sling, the grade, the permissible sling angle, the manufacturer and the conformity to the Machinery Directive (CE). Each individual part is additionally marked with the manufacturer's mark, a code for the load capacity and a traceability code. 

 

Due to their training and experience, qualified persons are technically capable of assessing the safe working condition of work equipment. A prerequisite is that they are familiar with the regulations, rules of technology, etc. 
The requirements for professional training, professional experience and recent professional activity of the competent person are specified in TRBS (Technical Rules for Industrial Safety) 1203 in accordance with § 2 Para. 7 BetrSichV.

 

The tag shows: the load capacity and nominal size of the sling, the quality class, the permissible sling angle, the manufacturer and the conformity to the Machinery Directive (CE). In addition, a reference to the last or next inspection of the sling.

Each sling chain must be marked with a unique identification number and assigned to a corresponding chain index card. The chain index card contains all relevant information on the sling chain and is also classically used as proof of the accident prevention inspections carried out at the legally prescribed intervals. The chain index card should contain at least the following data:
- Designation
- Grade
- Internal chain no.
- Load capacity
- Structure
- Manufacturer
- Test certificates on reverse side
A sample template of a chain index card is provided by DGUV Information 206-062, classic index cards in A5 format can be obtained from JDT or will be issued during an inspection by our inspection service if not already available. Alternatively, digital documentation is also possible, e.g. via the JDT sling database "JDT sBase".

 

According to DGUV Rule 109-017, the result of the test must be recorded and kept at least until the next test. For chain slings, this is usually done on the back of the chain index card.