All KÖCO Drawn Arc Welding Studs, standard studs and special purpose studs, are specified on the following pages.

However, should you require a stud which is not detailed here, please send us your drawings or discuss your welding problems with our specialists.

1. Stud material
KÖCO-studs are made from
St 37 -3 K to DIN 17100 (1). The steel St 37-3 K (1) is particularly noted for its excellent suitability to welding purposes.
Its properties can be supported by a works certificate in accordance with DIN 50049/2.2 (3) or 3.1 B upon request. Other works certificates can be provided at extra cost, upon special request. We guarantee mechanical properties in accordance with DIN ISO 898 (5), part 1 property class 48 for all threaded studs, unthreaded studs and similar studs of our standard range.

Tensile strength:
(Rm) min. 420 N/mm2
Yield strength:
(ReL) min. 340 N/mm2
Elongation:
(A5) min. 14%

For shear Connectors and concrete anchors made of St 37 -3 K (2) we guarantee the following mechanical
properties:
Tensile strength:
(Rm) 450-600 N/mm2
Yield strength:
(ReL) min. 350 N/mm2
Elongation:
(A5) min. 15%

Stainless steels:
Stainless steel KÖCO-studs are manufactured from material Type 1.4301 or 1.4303, conforming to DIN 17440 (4).
Guaranteed mechanical properties. Tensile strength:
(Rm) min. 500 N/mm2
Yield point:
(Rp0.2) min. 195 N/mm2
Elongation:
(A5) min: 25%
Studs made of other corrosion and acid resistant materials, such as 1.4401, 1.4541 and 1.4571 and other similar grades can be supplied upon request.
We guarantee the following mechanical properties for KÖCO concrete anchors and shear Connectors made from material Type 1.4301 (1.4303), grade class E 355 (see approval "Stainless steel materials" No Z-30.3-3
Tensile strength:
(Rm) 540- 780 N/mm2

Yield point:
(R p0.2) min. 350 N/mm2
Elongation:
(A5) min. 25%
KÖCO concrete anchors and shear Connectors of St 37 -3 K and 1.4301 (1.4303) have been approved by the Institut für Bautechnik (German Institute for Building Engineering), Berlin.

Refracfory KÖCO-studs are made from the following materials:
material No. 1.4713, 1.4742, 1.4762, 1.4828, 1.4841.
These materials are always in stock.

2. Stud dimensions
The stud dimensions can be found in the following dimension sheets.
The dimension "I1"is the stud length" After Welding", i.e. the delivered studs are 1- 5 mm longer than the specified nominal size, depending on the diameter of the stud (welding overdimension). (Exception: KKS, KHS)

3. Threads
The threads of KÖCO-studs are cold rolled and are manufactured in accor dance with DIN 13, part 20, tolerance 6g. Special threads available on request

4. Flux
KÖCO-studs are provided with a flux at the welding tip which enables easy ignition and stabilization of the welding arc and deoxidation of the welding pool.
The quality and amount of flux used are essential facfors for obtaining pertect and consistent weldings

5. Surface protection
If required, the following surface protection is available:
a) zinc-plated
b) zinc-plated and yellow chrome-plated
c) copper-plated
d) nickel-plated on copper-plated base
e) cadmium-plated
In case of zinc and cadmium plating, the plating is removed at the welding tip, to prevent contamination of the welding pool.

6. Ordering specifications
The following specifications are required when ordering:
a) Typeof stud
b) Stud diameter "d"
c) Stud length "L1"
d) material
e) Surface protection
Our standard range comprises the following Typees of studs.
TypeD: Fully threaded stud.
TypeP: Partially threaded stud. thread

length in accordance with DIN 32500 or thread length according to requirements
TypeR: Threaded stud with reduced minor thread diameter at the welding tip. Refer to the table for the reduction in length and diameter. Consequently the diameter of the weld fillet corresponds approximately to the nominal diameter of the stud thread
TypeS: Unthreaded stud

7. Ceramic Ferrules
Each Typeof stud requires its own particular ceramic ferrule. For welding reasons, KÖCO-studs always include ferrules. Ferrules are not available without the studs.

8. Weld Fillet
During the welding process, a weld fillet is formed around the stud at the transfer from the stud to the base metal, the dimensions of which are predetermined by the Typeof ferrule. The fillet diameter "d3" is usually greater than the nominal diameter of the stud.

(1) (S235J2G3 to EN 10025)
(2) (S235J2G3+C450)
(3) (EN 10204)
(4) (EN 10088-1)
(5) (EN 20898-1)

We reserve the right to technical change.