Because of the material properties, joining thermoplastic resins can lead to serious problems in the fields of construction, assembly and capacity. Due to decades of experience as a specialist in screw manufacturing, Schriever expanded its range of products to include the new Schriever STS® plus screws.
This screw is the best connection for thermoplastics and is the further development of the tried-and-tested Schriever STS® screw. It combines the usual quality with a high savings potential for the user in comparison with conventional thermoplastic screws.
Advantages for our customers
The Schriever STS® plus geometry provides further decisive advantages together with the well-known properties of the STS® screw. These are provided by:
- A considerably increased life-span of the screw joint in static and dynamic load
- Optimum connection and self-locking in the thermoplastic through improved thread geometry
- Increased pre-load through larger flank coverage on the supporting side
- The possibility of using shorter screws and/or smaller diameters with the same joint load; this produces savings potential for the customer
- Higher torsion and tensile strength
Our Service:
For the Schriever STS® plus to be used in the best way for your special purpose, our experts are available to provide you with help and advice. In our laboratory, your applications are optimised in terms of their joining and recommendations for construction are prepared. You receive a free test report.
High Flank Coverage with smaller Screw Depths
Through the optimised gradient, we also achieve a high flank coverage with a small screw depth. This results in a large pre-load for smaller surface pressure. The measurable advantages for the user: screw depths can be considerably smaller and the connections are therefore more cost-effective.
Reduction of Screw Length and/or Diameter
As a result of the smaller gradient, the Schriever STS® plus provides the option of using a smaller or shorter screw with the same flank coverage. For example, a Schriever STS® 50 can be replaced by a Schriever STS® plus 40 at the same screw depth. Likewise, with an unchanged screw diameter, the screw depth can be reduced if a Schriever STS® plus is used.
Minimised Loss of Pre-Load
Thermoplastic materials are inclined to creep under the influence of force, leading to a reduction in tension. This property is called relaxation. Due to the low surface pressure of the Schriever STS® plus thread, the pre-load loss is minimised and the screw connection has a very good long-term behaviour. Through the ideally designed thread geometry, the material damage caused by heating produced through large amounts of friction during the mechanical working is reduced.
Mechanical Strength, Dynamic Capacity
Through the enlarged core cross-section, the tensile and torsion strength is increased with the Schriever STS® plus screw. This benefits its use, even in ultra-reinforced thermoplastics. With dynamic pressure, a high capacity, vibration protection and vibration resistance of the entire joint is showed through the low gradient.
Suitability for repeated assembly
The repeated screwing of threaded screws is necessary for reasons of service and repairs and demands that the joint is inspected to that effect. The Schriever STS® plus screw was subject to this test during development and generally complies with the demands of VDE 0700 and DIN 57700.
Material
Schriever STS® plus are tempered to be high-strength as standard. Case-hardened steel, tempered, and stainless steel, rust-proof (A2 [1.4567], A4 [1.4578] and 1.4016 [magnetic]) can be produced on request.
Ordering example
STS® plus with nominal diameter = 3,0 mm • length = 12 mm • head = KN 6031 • Pozidrive
= KN 6031 STS® plus 30 x 12 -Z
On request, we can also deliver special forms which deviate from our standards.
These screws belong to the S-Connection supply concept.. |
