Loosening of bolts and nuts occurs when external forces such as vibration and impact are transmitted directly to the threaded part.

In our manufacturing facilities, nuts were frequently loosening due to vibration caused by high-speed operation.
We frequently checked for loose nuts, retightened them, and replaced them, but we were concerned that loose nuts could lead to defective products and machine breakdowns.

To solve this problem, we used commercially available nuts that prevented loosening, but we began to wonder, "Could we develop our own nuts that would never loosen?" We began to think, "Can we develop our own nuts that never loosen?

We came up with a variety of ideas, gave them concrete form, and after three years of trial and error, we succeeded in developing a "pair of nuts that never loosen.

Since the introduction of the Perfect Screw into our equipment, we have never had a single nut loosen.

Shrink-wrapping and integrating the nuts provides many advantages in terms of work and management.

(1) The upper and lower nuts can be attached to the bolt at once and tightened by hand, which improves workability.

(2) By perforating the shrink film, the perforations can be torn when the upper nut is fastened in the final process. This makes retightening confirmation more reliable.

(3) By coloring the shrink film M8 → red, etc., the size can be determined at a glance, which leads to improved workability. (4) When storing, the upper and lower nuts can be managed as a single unit, which facilitates inventory control.

(4) If the product is to be kept in stock for a long period of time, or if rust-preventive effects are required depending on the place of use, rust-preventive oil can be injected into the inside of the shrink film.

The fastening force of the Perfect Screw is created by the strong wedge effect.

By slightly tilting the shaft center of the concave tapered portion of the upper nut, the convex and concave portions of the fastening portion are in close contact over a wide area.

This produces a double wedge effect and a strong "no-loosening" fastening force.

Perfect Screws can be used in a variety of fields.

It is intended for use in a wide range of fields, including automobiles, industrial machinery and equipment, railroads, ships, bridges, steel towers, highways, and construction and civil engineering.