Bolt Engineer(c)

Principle & Mechanism of Tension-Nut

Accurate control of the bolt-tension with un-loosening function

When doing torque-fastening, the tension in the bolt is very incorrect. Because only 10% of the total torque is converted to the bolt-tension, due to being wasted by frictions at both the surfaces of bolt-threads & nut’s sitting floor.

Performace Data of [non-loosening], comparing some methods

Loosening torque values among some tightening methods with M36xP4x3000Nm
graph graph
Loosening Torque on M36 when tightened at tension of 128kN
graph graph

Technical Principle of Un-Loosening

Some (6~10 pcs.) press-screws,which are inclined by angle θ°, are assembled into the round nut-body with a Slope-Disk in θ°。

graph graph
  1. The body of Tension-Nut is going to loosen (=to turn anti-clockwise).
  2. The press-screw moving toward right-side to climb the slope θ°on the Disk.
  3. Even a little climbing the slope which causes remarkable increase of the tension in the bolt.
  4. As the result, the disk is pressed strongly against the floor-surface, which prevents from turning of the Disk itself.
  5. At the same time,the friction between both the threads of bolt/nut increases automatically which results in no loosening of Tension-Nut.

The principle of un-loosening by Tension-Nut is never by the friction-forces on the bolt-threads or between both the surfaces of the Disk & floor, but by increase of bolt-tension generated in the bolt-itself.
This means if the nut moves to get loosened, it gets automatically tightened more.

More Infomation :

Bolt-Engineer Co, Kobe, Japan

(Post code 651-2404) 255-6, Furusato, Iwaoka-Cho, Nishi-Ku, Kobe, Japan