DIN 981
Geometry of the documented technical selection. Check the supplied product drawing before substitution; universal equivalence with other designs is not claimed.
DIN 981
KM shaft locknut
A threaded locknut with four peripheral slots for positioning and axial retention of bearings and shaft components. Locking requires the retaining arrangement specified by the design.
- Dimensional range
- M10–M180
- Thread
- Metric · fine pitch
- Configuration
- KM shaft locknut
Technical drawing
- d
- metric thread
- P
- pitch
- d2
- outside diameter
- h
- height
- b
- slot width
- t
- radial slot depth.
Variants and dimensional data
The table identifies the reference technical selection. The supply configuration is reviewed against the enquiry.
Dimensions in mm. Identification drawing, not a manufacturing drawing.
| M | Pitch P | d2 outside | h height | b slot width | t radial depth |
|---|---|---|---|---|---|
| 10 | 0.75 | 18 | 4 | 3 | 2 |
| 12 | 1 | 22 | 4 | 3 | 2 |
| 15 | 1 | 25 | 5 | 4 | 2 |
| 17 | 1 | 28 | 5 | 4 | 2 |
| 20 | 1 | 32 | 6 | 4 | 2 |
| 25 | 1.5 | 38 | 7 | 5 | 2 |
| 30 | 1.5 | 45 | 7 | 5 | 2 |
| 35 | 1.5 | 52 | 8 | 5 | 2 |
| 40 | 1.5 | 58 | 9 | 6 | 2.5 |
| 45 | 1.5 | 65 | 10 | 6 | 2.5 |
| 50 | 1.5 | 70 | 11 | 6 | 2.5 |
| 55 | 2 | 75 | 11 | 7 | 3 |
| 60 | 2 | 80 | 11 | 7 | 3 |
| 65 | 2 | 85 | 12 | 7 | 3 |
| 70 | 2 | 92 | 12 | 8 | 3.5 |
| 75 | 2 | 98 | 13 | 8 | 3.5 |
| 80 | 2 | 105 | 15 | 8 | 3.5 |
| 85 | 2 | 110 | 16 | 8 | 3.5 |
| 90 | 2 | 120 | 16 | 10 | 4 |
| 95 | 2 | 125 | 17 | 10 | 4 |
| 100 | 2 | 130 | 18 | 10 | 4 |
| 105 | 2 | 140 | 18 | 12 | 5 |
| 110 | 2 | 145 | 19 | 12 | 5 |
| 115 | 2 | 150 | 19 | 12 | 5 |
| 120 | 2 | 155 | 20 | 12 | 5 |
| 125 | 2 | 160 | 21 | 12 | 5 |
| 130 | 2 | 165 | 21 | 12 | 5 |
| 135 | 2 | 175 | 22 | 14 | 6 |
| 140 | 2 | 180 | 22 | 14 | 6 |
| 145 | 2 | 190 | 24 | 14 | 6 |
| 150 | 2 | 195 | 24 | 14 | 6 |
| 180 | 3 | 230 | 27 | 16 | 8 |
A plain KM locknut is not self-locking: check the compatible locking washer and shaft keyway, or the alternative retaining device specified. Check pitch, bearing-face orientation and dimensional compatibility. Do not transfer loads or torque ratings certified for a particular brand to this geometry.
Table dimensions refer to the stated execution. DIN/UNI, polymer and special variants require verification of their own dimensions; they do not automatically inherit reference geometry, weight or performance.
Materials, classes, finishes and treatments
Executions are distinguished by reference, material, class and finish. DIN, ISO and UNI references do not imply dimensional equivalence or availability of every size in each material. Supply and batch documents require quotation confirmation.
| Execution reference | Material | Class / hardness | Documented finishes |
|---|---|---|---|
| DIN 981 | Steel | 4.8 | GEOMET 321A; Plain; Yellow zinc plated; Zinc plated |
“To be specified” is a requirement not established by this selection; it does not imply class 70/80, HV hardness or an automatic finish. Steel property classes do not apply to nylon/polyamide; PA6 and PA66 are distinguished only where stated. For nuts with non-metallic inserts, the material shown is the body material.
Documentation
Download Dueemme data sheet ↓| Document | Status |
|---|---|
| Declaration of conformity | Subject to order agreement |
| Material certificate | Subject to order agreement |
| EN 10204 2.2 test report | Subject to order agreement |
| EN 10204 3.1 inspection certificate | Subject to order agreement |
| Dimensional inspection report | Subject to order agreement |
| Coating report | Subject to order agreement |
| Other documentation | Subject to order agreement |
Batch documents are not automatically included: specify your requirements in the RFQ.
ISO, DIN and UNI: key differences
Enquire about this configuration
State your requirements: material, property class and finish will be assessed for your enquiry.
Other materials, property classes and finishes available on request. Each configuration is assessed against the enquiry specification.
The size you need, including custom specifications
Other diameters, lengths, materials and finishes can be assessed on request. For dedicated production, we agree geometry, requirements and minimum quantities with the customer.
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