In 1895, France developed the world's first pneumatic tire. In 1935, China's Shanghai Greater China Rubber Factory produced the first automobile tire. In 1948 France began to produce radial tires. In the 1980s, after the production of bias tires for about 45 years, China began to implement industrial radial tires. In the following years, China's tire industry has developed rapidly and become a tire producing country. In 2016, China's total tire production reached 610 million, including 565 million radial tires, and the meridian rate reached 92.6%. A small number of bias tires are only used for general vehicles and certain special vehicles used in low speed applications.

With the continuous development of China's national economy, the tire industry will further adapt to the development speed of the national economy and further increase production and quality. In 2017, the total tire production reached 635 million, including 591 million radial tires, and the meridional rate increased to 93%.

In order to popularize tire production knowledge, this article briefly introduces the basic process technology of tire production for reference.

First, the tire overview

1.1 Classification of tire products
The term tire is a general term for tire products. It is used for all kinds of tires on various transportation and transportation tools. The actual classification of products is as follows.

1.1.1 Classification by purpose
(1) Cars and light truck tires: mainly used for pneumatic tires on small cars and small light-duty vehicles.
(2) Truck tires: mainly used for pneumatic tires on trucks, buses and their trailers.
(3) Construction machinery tires: tires for wheeled construction vehicles and construction machinery. Divided into loader tires, scraper tires, grader tires and roller tires.
(4) Industrial vehicle tires: mainly used for pneumatic tires, solid tires and semi-solid tires on industrial vehicles. Divided into forklift tires, battery car tires and flat tires.
(5) Agricultural tires: mainly used for pneumatic tires on agricultural machinery and agricultural vehicles. Divided into tractor tires, combine harvester tires and agricultural machinery tires.
(6) Forestry tires: mainly used for pneumatic tires on forestry machinery and forestry vehicles.
(7) Aviation tires: used for pneumatic tires on aircraft.

1.1.2 Classification by structure
Currently used are the following two categories:
(1) bias tire
A pneumatic tire in which the adjacent layers of the carcass ply and the buffer layer intersect each other and are at an angle of less than 90o with the center line of the crown.
(2) radial tire
The carcass ply cord is at a 90o angle to the centerline of the crown, or a pneumatic tire that is aligned at a 90o angle and is hooped by the belt.

1.1.3 Classification by tube or tube
(1) There is a tube tire: a pneumatic tire in which the inner tube is to be assembled in the inner cavity of the tire, the compressed air is filled in the inner tube, and the inner tube is provided with an inflation check valve (ie, a valve).
(2) Tubeless tire: a pneumatic tire without inner tube in the tire. The compressed air is directly filled into the inner cavity of the tire. The inner liner and the bead of the inner surface of the tire are combined with the wheel rim, and self-sealing is performed by internal pressure to maintain the inside of the tire. The pressure inside the chamber.

1.2 Tire sidewall tire specification and other methods
Tag content
1.2.1 Tire specification representation
(1) General tire specification method
(2) International standard representation of tire specifications
When the tire specifications are expressed by international standards, the content is relatively complicated, and is usually expressed by four dimensions: tire section width (mm), tire flatness ratio (%), tire structure code, and rim nominal diameter (in). Some tires are additionally coded with the tire load index and speed grade. Most of this representation is used for passenger car radial tires.

1.2.2 Other markings on the sidewall of the tire
In addition to the tire specifications marked on the sidewall of each tire, the following contents are also marked:
(1) manufacturer name, country name, trademark;
(2) Maximum load and inflation pressure;
(3) Tire frame materials, such as all-steel radial tires, marked "ALL Steel";
(4) Tubeless tire label "TUBELESS", tube tires without marking;
(5) Tire level, such as 14PR, 16PR, means 14 levels, 16 levels, but does not represent the actual number of layers of tire carcass ply. Car radial tires are not marked grade, the level is mainly marked on the sidewall of the truck tire. The letter PR is composed of the English word Ply Ratimg;
(6) Conditions of use, all-weather tire marking "ALL WEATHER", snow tire marking "SNOW", winter tire marking "WINTER";
(7) The tread pattern can be re-engraved after the tread pattern is worn, "REGROOVABLE";
(8) Tires approved by the US and Canada Transportation Bureau are marked with the “DOT” mark.

In addition, some tires still have production numbers, tread wear mark positions and inspection marks. Some can also tag other content as needed to guide the user.

With the advancement of technology, the European Union, the United States and Japan and other countries and regions have introduced the "tire labeling method", requiring tires to be labeled, including fuel efficiency, rolling resistance, wet grip and rolling noise. RFID tags can also store these parameters and their ratings.

From July 1, 2016, China's tire products began to implement tire ID card implantation of radio frequency identification (RFID) electronic tags, read the relevant data through the collection terminal, and cooperate with the management software to achieve the record of tire life cycle data and Trace back.

1.3 Speed level and load index
1.3.1 Speed Level
Each type of tire has a corresponding speed level, and each speed level corresponds to a maximum speed, as shown in Table 1. However, the general-class sedan of the expressway can be selected as a class H tire. Generally, it is sufficient to select a T-class tire.

1.3.2 Load index
In the era when cotton fibers were used as the skeleton material, the number of layers of the ply represents the load capacity of the tire, and later it was changed to the level of the ply (the level and the number of layers are not a concept). In the case of the continuous development and application of new high-strength cords, the “load index” is used instead of the “level” representation. The international standard divides the foreseeable load into 280 grade load indexes from small to large, each index represents a level of “tire load capacity”, and the index difference of adjacent grades is about 3%. The minimum load index is “O”, the corresponding load is 45kg (0.44kN), the highest load index is 279, and the corresponding load is 13000kg (1334kN).