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STAUFF Safety Lock Washer (Type SI DIN 93 – Standard Series)
The STAUFF Safety Lock Washer (Type SI DIN 93 – Standard Series) is an advanced locking device designed to prevent Type AS hexagon head screws from loosening. Compliant with the rigorous DIN 3015, Part 1 standard, this washer is fully compatible with the dimensions of all Standard Series groups, from Group 1 to Group 8. Precision-manufactured, it ensures reliable mechanical clamping of the clamp body. The available product code families are: SI-6.4-DIN93-W3, SI-6.4-DIN93-W5.
STAUFF Safety Lock Washer (Type SI DIN 93 – Standard Series)
The STAUFF Safety Lock Washer (Type SI DIN 93 – Standard Series) is an essential mechanical component for ensuring the structural integrity of fastening systems. The primary function of these Type SI safety washers is to act as locking devices specifically designed to permanently prevent the accidental loosening of Type AS hexagon head screws. During installation, the operating principle requires precise mechanical bending: the longer tab must be bent downwards towards the side of the clamp body, while one side must be bent upwards so that it rests firmly against one of the flat faces of the hexagon bolt head. This fastening process ensures that vibrations or dynamic loads do not compromise the tightness of the system.
Manufactured according to the parameters of DIN 3015, Part 1, Type SI safety washers (DIN 93) feature a single tab (1 tab). They are designed for complete versatility within their category and are suitable for use with all Standard Series group sizes (STAUFF Groups 1 to 8, corresponding to DIN Groups 0 to 8). The dimensional tolerances are precisely calibrated, with specifications including an inside diameter (ØD1) of 6.4 mm (0.25 inches) and an outside diameter (ØD2) of 19 mm (0.75 inches). The tab width (B) is 7 mm (0.28 inches), while the length (L) is 18 mm (0.71 inches). The component features a radius (R) of 4 mm (0.16 inches) and an extremely thin yet durable thickness (S) of 0.5 mm (0.02 inches).
To meet the different environmental and operating requirements of the hydraulic sector, the STAUFF Safety Lock Washer (Type SI DIN 93 – Standard Series) is available in two main material variants. The first option, identified by material code W3, is made of Carbon Steel with a zinc/nickel-plated surface treatment to ensure adequate corrosion resistance. The second option, identified by code W5, is made of premium-quality V4A stainless steel, specifically grades 1.4401 or 1.4571 (corresponding to AISI 316 or 316 Ti). Additional alternative materials and special surface finishes are available upon request by contacting STAUFF directly. The standard ordering code follows a nomenclature that identifies the type (SI), size (6.4), standard (DIN93) and material (e.g. W3 or W5).
| Feature | Value |
|---|---|
| Washer Type | Safety washer with 1 tab |
| Reference Standard | Type SI (DIN 93), DIN 3015 Part 1 |
| Group Compatibility | STAUFF Groups 1-8 / DIN Groups 0-8 |
| Compatible Screws | Type AS hexagon head screws |
| Inside Diameter (ØD1) | 6.4 mm (0.25 in) |
| Outside Diameter (ØD2) | 19 mm (0.75 in) |
| Width (B) | 7 mm (0.28 in) |
| Length (L) | 18 mm (0.71 in) |
| Thickness (S) | 0.5 mm (0.02 in) |
| Material W3 | Carbon steel, zinc/nickel-plated |
| Material W5 | V4A Stainless Steel 1.4401/1.4571 (AISI 316/316 TI) |
| Product Code | Standard | Material |
|---|---|---|
| SI-6.4-DIN93-W3 | DIN 93 (1 tab) | Carbon Steel (W3) |
| SI-6.4-DIN93-W5 | DIN 93 (1 tab) | V4A Stainless Steel (W5) |