Holland Scaffold Supply | HSS - Couplers
EN S355MC - EN S235JRC+C
Couplers for scaffolding
Holland Scaffold Supply's right angle and swivel wedge couplers are designed for precision, durability, and consistent performance. Each coupler consists of components made of carefully selected materials:
- Body and wedges – manufactured from EN S355MC (1.0976), a thermomechanically hot-rolled fine-grained structural steel with a minimum yield strength of 355 MPa, designed for cold forming operations such as bending and folding. This material provides superior strength, formability and impact resistance for demanding scaffolding structures.
- Wire – manufactured from EN S235JRC+C (1.0122) cold-drawn bars, providing improved dimensional accuracy, a glossy surface and a uniform microstructure. Its excellent weldability and bending performance (180° flat bending without cracking) make it ideal for the production of couplers.
Each coupler is hot-dip galvanized according to NEN-EN-ISO 1461:2009, which provides long-term protection against corrosion. This ensures that our couplers maintain their integrity and strength even under harsh environmental conditions.
Traceability and identification
Each coupler is provided with a permanent, hard stamp in the wedge, which shows the HSS logo, the EN 74 Class B marking, the batch number and the year of production. This system guarantees 100% traceability to material and production data. Daily tests verify compliance with EN 74 parameters such as slip resistance, torque, pull-out force and bending moment. This traceability guarantees a demonstrable origin and quality assurance for every coupler in use.
Testing and certification
HSS performs mechanical performance tests according to EN 74 Class B, including slip, failure and weld strength evaluations. The minimum required test results are: Fs = 15 kN, Ff = 30 kN, Fp = 30 kN, MB = 15 kNm/rad (steel) or 13 kNm/rad (aluminium), based on a safety factor of 1.65. Each batch of couplings is accompanied by a 3.1 Material Test Certificate (EN 10204) to ensure full traceability and compliance.
Packaging and logistics
Couplers are packed in durable, stackable cardboard boxes (500 pieces per box), placed on plastic pallets and sealed with shrink film for water-repellent protection. A 40-foot container can accommodate approximately 13,500 right-angle wedge couplers or 3,000 swivel wedge couplers. This packaging enables efficient container loading, fast transshipment on an open trailer and direct delivery to construction sites. Indoor storage is not necessary thanks to the moisture-resistant packaging.
HSS also creates a detailed delivery schedule for long-term projects, providing customers with transparent updates on production, shipping, and delivery. Combined shipments of pipes and couplers are possible to optimize logistics and minimize handling.
Quality assurance and control
At Holland Scaffold Supply, sustainability is proven through continuous monitoring. Our quality department carries out load and weld tests on a daily basis and marks each inspected coupler with a "checked and approved" mark as proof of a successful inspection. Every two weeks, our couplers undergo rigorous salt spray corrosion tests, which simulate prolonged exposure to harsh environments. In addition, tests at -30 °C confirm that material properties, tolerances and clearances remain consistent in extreme cold. Couplers are cooled, assembled, adjusted and loaded under these conditions to check their mechanical reliability. Only couplers that pass all tests, without cracking, deformation or slipping, receive the HSS quality mark.
Our right-angle and swivel wedge couplers are identical to Van Thiel couplers and fully comply with the EN 74 Class B requirements. All production processes are carried out under ISO 9001 certified quality management systems, ensuring consistent product quality and full compatibility with global scaffolding systems.
In addition to internal tests, independent institutes, such as TÜV, carry out biennial checks on mechanical and welding performance. This multi-layer approach ensures that HSS couplings not only meet but exceed EN 74 requirements in terms of durability and consistency.
