The wheel system consists of a hub (axle), spokes, wheels, inner tubes, and outer tubes. Among them, the hub, spoke, and rim form a wheel group, which is the key to determining whether the bicycle rolls smoothly. Additionally, when replacing these accessories, it is important to pay attention to the size to prevent the two ends from not falling properly...

The present invention discloses a structure for preventing the loosening of the threaded connection between the middle axle of a bicycle, which is used to fasten the bolt between the middle axle of the bicycle and the crank in the same direction as the movement direction of the crank. The left crank of the central axis and the direction of cycling is fastened with left-hand bolts. The present invention uses a square conical surface to position the middle axle and left crank of the bicycle, and then fastens them with left-hand bolts. The left counterclockwise movement of the crank during cycling causes the fastening bolts to tighten as they are used, effectively solving the potential loosening danger of the existing bicycle structure and eliminating safety hazards

The grades of metric bolts are: 4.6; 4.8; 5.8; 6.8; 8.8; 9.8; 10.9; 12.9.

The grades of metric nuts are: 4; 5; 6; 8; 10; 12 of which 4; 5 is the strength grade of thin nuts.

In some cases, the strength of nuts is somewhat lower than that of bolts, mainly due to the fact

that bolt failures are often not easily detected, sometimes sudden, and nut failures are more

easily detected. It also considers the safety aspect. This can ensure that when used together, the

life of the screw is longer than that of the nut, and it will be cheaper and easier to disassemble

and replace fasteners.

Cotter pin：
Cotter pin is a kind of metal hardware, commonly known as spring pin, safety pin!

The cotter pin is a mechanical component that can be greased to avoid damaging the hole wall.

Cotter pins are commonly made of high-quality steel and materials with good elasticity.

Hex bolt

Outer hexagon bolt/screw: good self-locking; Large pre-tightening contact area and large pre-tightening force; The length range of full thread is wider; There can be reamed holes, which can fix the position of parts and bear the shear caused by transverse force

2023 Chinese New Year holiday tentative total 15 days
January 14 -January 28 --- 15 days (Sunday) official work

What's the advantages of Socket screws?
The screw head of the inner hexagon screw is round outside, and the middle is a concave hexagon. Such a structure can bear more load. It has six force surface, compared with only two flat and cross screw more withstand the screw.

This torx screw is suitable for Automotive fasteners, aerospace fasteners, high-speed rail fasteners, new energy fasteners, mechanical fasteners, industrial fasteners, engineering fasteners and other domestic and industrial application.

T-bolts, called hammer bolts in the European standard, are made of carbon steel with galvanized or nickel-plated surfaces

Flat washer is a kind of flat washer, which is mainly used to increase and tighten the contact area between screws and some large equipment. When using flat washer, it is usually suitable for the nut and nut to cooperate with each other. When storing flat washer, it must have essential important characteristics within the most effective sealing time:

What is a T-nut

Nut is a kind of part that is screwed together with a bolt or screw rod with a nut for fastening.
According to different uses in manufacturing machinery, the same element can be divided into
several categories according to different materials, including carbon steel, stainless steel,
non-ferrous metals, etc. T-nut is a kind of nut that looks like t. T-nuts are not only easy to
install and unload, but also easy to install parts at any position, which can greatly improve
labor productivity, which is also the reason why T-nuts can be widely used in T-grooves
of various milling machines.