Start with the problem: if bolts turn loose under vibration, use Original washers; if joints settle and lose tension, use X-series. Then match the material to your bolt, the size to your bolt diameter, and choose the enlarged type for big or slotted holes.
Step 1: what is going wrong?
Pick the product family from the problem you see.
| Your situation | Product |
|---|---|
| Bolts turn loose under vibration | Original washers |
| Joints settle or lose tension over time | X-series washers |
| Structural steel, HV and HR bolt sets | Steel construction washers |
| Heavy vehicle wheels | Wheel nuts |
| Fast assembly, fewer loose parts | Combi nuts |
| Something special | Custom solutions |
Signs of slackening include soft materials such as aluminium or copper, gaskets, painted or coated parts, short bolts and stacks of several parts.
Step 2: match the material to the bolt
- Steel bolt: steel washer.
- Stainless bolt: stainless steel washer.
- Very corrosive or very hot conditions: ask us about special alloys such as 254 SMO, C-276 and 718.
Step 3: pick the size
The washer size follows the bolt diameter. An M6 bolt takes an M6 washer, an M16 bolt takes an M16 washer. Original washers cover a wide range, from M3 to M130.
Step 4: standard or enlarged?
Use the standard washer for normal holes. Choose the enlarged type (marked sp) when the hole is big or slotted, so the washer still sits fully on the surface.
Step 5: how many pairs?
- Bolt into a blind (tapped) hole: one pair under the bolt head.
- Through bolt with a nut: one pair under the head and one pair under the nut.
How to read the part code
Original washer codes describe the part. For example, NL6spss means Nord-Lock, fits M6, enlarged (sp), stainless steel (ss). NL16 is a standard steel washer for an M16 bolt.
Check these limits
- Original washers are designed for bolts up to property class 12.9 (steel) and A4-80 (stainless).
- X-series washers are designed for 8.8 and 10.9 bolts.
- Do not use them on surfaces harder than the washer, or on joints that are not tightened to a set preload.
If anything is unclear, send us the bolt size, grade, materials and what you are seeing. We will recommend the right part.