Tubular cable lugs for special applications

The specialist products: tubular cable lugs for special applications

Many electrical engineers will certainly know from experience the issue relating to the fact that standard cable lugs cannot be used, as they are not a precise fit with conductors, for example. The issue when trying to push a fine or superfine stranded conductor into a cable lug is that the cable splays and a few strands do not find their way into the cable lug. In order to prevent these difficult situations from happening in the first place, Klauke has a wide range of special cable lugs on sale. Please contact us if you are unable to find the solution you require in our catalogue.

All conductor classes can be connected without any trouble using these special cable lugs. Their design is aligned with the special properties of the various conductor classes as defined in DIN EN 60228. These specifically include:

  • Class 1 round shaped single-stranded conductors (re) (also known as solid conductors)
  • Class 2 round shaped stranded conductors (rm)
  • Class 5 fine stranded conductors (also known as flexible conductors)
  • Class 6 superfine stranded conductors (also known as ultra-flexible conductors)
F-cable lugs: specialists for fine and superfine stranded conductors
The use of "F" series tubular cable lugs can prevent the common problems of inserting spliced Class 5 and 6 fine and superfine stranded conductors according to DIN EN 60228. They are suitable, for example, for processing larger cable cross-sections in switch cabinet construction, in galvanization plants or for use in rail vehicles. F-tubular cable lugs have a larger tubular inside diameter than "standard" cable lugs. They are also flared in a conical shape in complex manufacturing processes, thus ensuring improved cable insertion. F-tubular cable lugs therefore allow the conductor to be inserted easily and securely.

This also has a number of safety-related impacts: Cross-section tapering as a result of stranded wires that have snapped off or not been inserted is prevented, thus ensuring the full cross-section of the conductor remains in place.

F-tubular cable lugs also have markings. These markings consist of the following: The “710F12 K12-150f” feature stands for

  • K: Manufacturer code (Klauke in this particular instance)
  • 12: Metric bolt dimensions of the connecting bolt bore (in this case M12 bolt)
  • 150: Nominal cross-section of conductor in mm²
  • f: “F”-series tubular cable lug (fine stranded)
  • 710F12: Cable lug item number

Quad-point crimping and/or notch crimping using suitable tools are regarded as proper crimping methods for F-cable lugs.

Suitable for use with "F" series tubular cable lugs, Klauke also offers suitable butt connectors for conductor extensions or repair purposes. The recommended crimping types are in line with those for F-tubular cable lugs. “F”-series cable lugs and butt connectors are made from electrolyte copper tubes.

In order to ensure there is corrosion protection in place, these cable lug types are also tin plated. The standard conductor cross-sections are between 10 mm² and 300 mm². In addition to straight versions, there are also angled 45° or 90° versions available, along with models featuring an inspection hole, which you can use in practice to identify whether the conductor has been pushed completely into the cable lug.

Cable lugs made by Klauke are annealed as part of a special manufacturing process. As a result, any tension is removed from the material and the risk of breaking is significantly reduced, thus ensuring extra safety.

From the Klauke product range:

> Tubular cable lugs, Cu, F-series

> Angle tubular cable lugs, Cu, 90° angled, F-series

Tubular cable lugs for single stranded conductors (re)
Single stranded conductors of class 1 according to DIN EN 60228 are best crimped with "E" series tubular cable lugs (cable lugs for solid conductors). These are constructed from tin plated electrolytic copper. The special feature of this series of tubular cable lugs is its adapted tube diameter, which ensures optimum crimping of solid conductors. The range of applications includes sectors requiring the use of solid conductors – for example in transformer and motor construction. For these cable lugs we recommend double indent crimping and hexagonal crimping.

Tubular cable lugs for single strand conductors can be identified by their small diameter as well as by their marking: the last character on the stamp is an ‘E’ for "eindrähtig" (single stranded in English). For example: KL 10 50 E.

Matching butt connectors and T- and cross-connectors with corresponding inner diameters for single strand conductors are also available for ‘E’ series tubular cable lugs.

From the Klauke product range:

> Tubular cable lugs, Cu, solid conductor type

> Butt connectors, Cu, solid conductor type

> T-connectors, Cu, solid conductor type

> Cross-connectors, Cu, solid conductor type

Tubular cable lugs for narrow switch gear connections
Fitters involved in control cabinet construction face many challenges. Aside the fact that confined spaces usually hamper progress anyway, connecting conductors to powerful switch gear proves especially tricky – from a certain conductor cross-section onwards, conventional tubular cable lugs do not fit into connecting terminal provided. For these difficult applications, special tubular cable lugs for switchgear connections have been developed ("SG cable lugs"). They have a much narrower palm which is readily compatible with the switch cabinet connection.

The palm of these cable lugs is not only much narrower than that of a conventional cable lug, it is also slightly thicker. The reason lies in production: the same quantity of electrolytic copper is used as for a traditional tubular cable lug.

This type of tubular cable lug is therefore suitable for use in control cabinet construction. These can be processed in precisely the same way as “standard type” tubular cable lugs. Suitable crimping profiles for this would be hexagonal crimping, indent crimping or notch crimping.

The boreholes are adapted to the terminal dimensions of current switch gears. Designs with a practical inspection hole are also available.

We strongly advise against cutting off the palm sides of standard tubular cable lugs to make it fit

into the connecting terminal of the switch gear. Manipulations like this can be very dangerous. In the worst case scenario there is a risk of fire, as the cross-section of the cable lug is reduced.

From the Klauke product range:

> Tubular cable lugs for switch cabinet connections
Stainless steel and nickel – tubular cable lugs for aggressive or high temperature environments
Hostile environments also demands special cable lugs. Tubular cable lugs made of stainless steel and nickel are extremely resistant and ideally suited to crimping with copper conductors.

Stainless steel tubular cable lugs are extremely resistant to acid and corrosion, which is why they are best suited to use in the chemical and food industries, or for areas in which the material is exposed to sea water. Stainless steel is not only extremely resistant to acid, but also resistant to high temperatures. As a result, stainless steel cable lugs can also be used without difficulty in ambient temperatures of up to 400°C.

If the temperature exceeds this and cable lugs are needed for extremely high temperatures, for example in the thermistor range of annealing or heat furnaces, nickel tubular cable lugs offer the best solution. These can withstand maximum temperatures of up to 650 °C.

Stainless steel and nickel tubular cable lugs are suitable for stranded and fine stranded conductors of classes 2 and 5, and for pre-rounded sector shaped conductors.

For cable lugs made of these resistant materials, we recommend indent crimping, as well as for butt connectors with butt mark.

From the Klauke product range:

> Tubular cable lugs, stainless steel

> Tubular cable lugs, nickel

Tubular cable lugs, nickel, fork type