STAUFF Safety Locking Plate (Type SI – Twin Series)
Designed in accordance with DIN 3015, Part 3, the STAUFF Safety Locking Plate (Type SI – Twin Series) is essential for use with Type AF stacking bolts. Type SI prevents the bolt from loosening, while the Type SIV variant also prevents the upper clamp from rotating. Manufactured from zinc/nickel-plated carbon steel (W3) and V2A/V4A stainless steel, these plates ensure optimum securing for STAUFF Groups 1D to 5D.
The available product code families are: SI-1D-W3, SI-2-5D-W3, SIV-1D-W3, SIV-2-3D-W3.
The STAUFF Safety Locking Plate (Type SI – Twin Series) is an essential mechanical component within hydraulic pipework fastening systems, operating in strict compliance with DIN 3015, Part 3. This plate is specifically engineered for use in combination with Type AF stacking bolts. The technical design is available in two main construction variants, each intended to address specific stability issues under load or vibration. The basic model, identified as Type SI (Safety Locking Plate SI), performs the primary function of preventing the stacking bolt from loosening. The second variant, Type SIV (Safety Locking Plate SIV), further increases the safety level of the system: in addition to securing the stacking bolt to prevent loosening, its mechanical design also prevents the upper clamp from rotating.
The safety locking plates feature dimensional parameters closely linked to the relevant STAUFF Group, providing modular coverage for different pipe sizes. Type SI covers STAUFF Groups 1D to 5D, corresponding to DIN Groups 1 to 5. In this configuration, the plate thickness (S) remains constant at 0.5 mm, with lengths (L) ranging from 27 mm for Group 1D to 86 mm for Group 5D, and centre distances (B1, B2) proportioned accordingly. The Type SIV variant is available for STAUFF Groups 1D to 3D, corresponding to DIN Groups 1 to 3. For Type SIV, the thickness (S) is increased to 1 mm and a height (H) of 7 mm is introduced, which is required to provide the anti-rotation locking function for the upper clamp during operation.
To meet different environmental and operating requirements, STAUFF offers three main material codes for these components. Code W3 identifies plates manufactured from carbon steel with a zinc/nickel-plated surface finish, providing reliable corrosion resistance in standard industrial environments. Stainless steel options are available for applications in aggressive environments: code W4 indicates V2A stainless steel, grades 1.4301/1.4305, equivalent to AISI 304/303, while code W5 indicates V4A stainless steel, grades 1.4401/1.4571, equivalent to AISI 316/316 Ti, providing maximum protection against chemical agents and oxidation. Additional materials and alternative surface finishes can be supplied upon specific request, subject to technical availability. The use of the STAUFF Safety Locking Plate (Type SI – Twin Series) in multiple clamp assemblies therefore maintains the initial tightening torque, significantly reducing unscheduled maintenance and improving the overall stability of the hydraulic system.
| Feature | Value |
|---|---|
| Reference Standard | DIN 3015, Part 3 |
| Series | Twin Series |
| Component Compatibility | Type AF Stacking Bolts |
| Type SI Model Function | Prevents the stacking bolt from loosening |
| Type SIV Model Function | Prevents the bolt from loosening and the upper clamp from rotating |
| Plate Thickness (Type SI) | 0.5 mm |
| Plate Thickness (Type SIV) | 1 mm |
| Material W3 | Zinc/nickel-plated carbon steel |
| Material W4 (Available for Type SI) | V2A Stainless Steel (1.4301/1.4305 – AISI 304/303) |
| Material W5 | V4A Stainless Steel (1.4401/1.4571 – AISI 316/316 Ti) |
| Model / Family (Standard Options) | STAUFF Group | DIN Group | Reference Material |
|---|---|---|---|
| SI-1D-W3 | 1D | 1 | W3 (Carbon steel) |
| SI-2-5D-W3 | 2D – 5D | 2 – 5 | W3 (Carbon steel) |
| SIV-1D-W3 | 1D | 1 | W3 (Carbon steel) |
| SIV-2-3D-W3 | 2D – 3D | 2 – 3 | W3 (Carbon steel) |