DEMU rebar coupler systems for reinforcing steel meet the requirements of BRL 0504. The alignment, cutting and bending of the male connector bars and female socket bars meet the requirements of section 2 of BRL 0503 “Tack welded reinforcement mesh, reinforcing structures and bending and interweaving”. The reinforcing steel of these connectors is of FeB 500 HWL and FeB 500 HK meets the requirements of section 2 of BRL 0501 “Reinforcing steel” and hence of section 3 “Glossary of terms” and section 5 “Requirements of NEN 6008".

 

See our KOMO productcertificate K-7044. category 1 for mainly statical loaded concrete constructions.

See our KOMO Productcertificate K53316, category 2 applicable in dynamic loaded concrete constructions

 

In NEN 6008 (July 2008) the quality indicators HWL, HK and HKN are invalid and now there are ductility classes A, B and C introduced. were introduced. Applied reinforcing steel has the quality B500B or B500C. The DEMU rebar coupler system is also authorised by the German building authorities, Zulassung Nr. Z-1.5-139.

The DEMU rebar coupler system is ideal for 100% load-bearing through fastenings in reinforcing steel.

• The system is available in the following diameters (Ø): Ø12, Ø16, Ø20, Ø25, Ø32 and Ø40.
• The female socket bars are available as type 4010 (for round 40 type 2010), male connector bars are available as type 2020 and with flattened end type 2020-P. With a combination of the type 2000 assembly tool and an electric appliance, the 2020-P can be quickly screwed into the female socket bars.
• Tolerances: 4010, 2020 and 2010 (round 40): +5mm/-2Øk, according to NEN 6146 "Steel bars for the reinforcement of concrete".
• The anchors can be bent on request. There is a minimum bending point (Lb) to not damage of the thread or the connector socket. Bending is done by means of a 5*ØD former. During bending elongation (V) occurs and this results in a Y dimension of (L+V=Lb+Y).
• It is also possible to supply a U-bend. Contact our sales department for the possibilities.
• If the height-to-height distance between multiple inserted bar anchors is small, it is possible to screw the male connector bar in by means of the DEMU 4015 connector.
• Anchors with a different length can also be supplied.
• DEMU specials: 4030/4035/2040: 

    4030 is made up of reinforcing steel with a connector at either end.

    4035 is made up of reinforcing steel with on one side a connector and one side rolled thread.

    2040 is made up of reinforcing steel with rolled thread at either end.

 

DEMU supplies a torque wrench for the correct tightening torque

ØD        12         16          20          25         32        40

Nm        75        100        160         250       400      400

Tolerance tightening torque +/- 5 %

 

All joints may be used in tensile, compressive and shear applications. The male connector bars must be tightened to the prescribed torque (Nm). In order to determine the working value for strength of the steel in the anchor,  a material factor y_m must be applied to the elastic limit. See NEN 6720 section 6.2 “Reinforcing steel”. To determine the minimum anchorage length, please refer to NEN 6720 section 9.6 “Length of reinforcing steel anchorages". The type 4010 is suitable for through fastening in combination with DEMU type 2020 and with 2020-P and for constructive anchores. The 4010 female socket bar anchors must always be checked in accordance with NEN 6720 section 9.6 “Length of reinforcing steel anchorages.” and 9.16 “Embedded anchors”.

 

DEMU rebar coupler system is developed for making mechanical connectors with KOMO certificated reinforcing steel, quality FeB 500 HWL and FeB 500 HK in conformity with NEN 6008. The system is applicable in category 1: mainly statically loaded constructions conform BRL 0504. The DEMU rebar coupler system is tested with a tension ripple of 2 óa = 60 N/mm² at 2 million tension changes and an upper tension of 0.6 R_e:k.

 

In NEN 6008 (July 2008) the quality indicators HWL, HK and HKN are invalid and now there are ductilityclasses A, B, and C introduced. Applied reinforcing steel has the quality B500B or B500C.

 

To fasten the shuttering of type 4010 (and 2010 round 40) use can be made of various accessories including types 2250, 2280 and 2600. The plastic sealing cap type 2244 forms protection against penetrating dirt and concrete water. For extra protection we also advise greasing the internal screw thread.

 

 

The female socket bars and male connector bars must be stored free of dirt so they can be screwed into each other without problems. The accessories ensure protection besides fixing to the shuttering. For further protection against penetrating dirt and concrete water we also advise greasing the inside of the connector. The male connector bars must be turned in using a torque wrench set to the correct tightening torque.

 

You can find the length of the connector of a 4010, 2020 round 40 and a  3010 (A4-80) at FAQ, general point 6.