China is the world's largest tire producer, at present, the domestic annual output of various tires more than 0.2 billion. In the existing tire factory, with the exception of very few manufacturers (the total annual output of these manufacturers is less than one-tenth of the total domestic tire production) still retain part of the water tire vulcanization, almost all manufacturers are using the bladder shaped vulcanized tires. This paper expounds the current situation and market development trend of tire curing bladder used in tire curing production in China, and makes a brief comparison of several production processes of tire curing bladder in China.

 

Overview of tire curing bladder market

 

According to industry-related information statistics, the total demand for various tire capsules in China is about 4.5 million, of which passenger tire vulcanizing capsules account for about 55% of the total, truck tire vulcanizing capsules account for about 35% of the total, and others (including agricultural and engineering tire vulcanizing capsules) account for about 10% of the total. The total market capacity is equivalent to about 2.5 billion yuan.

 

In terms of market production, supply and marketing, the current product quality of the capsule market is in short supply, the user manufacturers pay first and then deliver the situation is very common, so most tire capsule manufacturers benefit better. In the market supply chain, domestic tire capsules are mainly divided into two parts: import and domestic production. Among them, domestic capsules account for about 75% of the total demand, and the rest are imported. The imported ones are mainly used to produce high-grade passenger tires and large all-steel radial tires.

 

At present, the main manufacturers of tire capsules in China are: Shandong Dawang Jintai Group, which mainly produce various tire vulcanization capsules and tire molding reverse capsules, with an annual maximum production capacity of about 300000. Shandong Xishui Group Yongyi Rubber Co., Ltd. produces about 150000 tire capsules annually. Tianjin Dajin Capsule Factory produces about 300000 tire capsules annually. Nanjing Capsule Factory produces about 150000 capsules annually; jiangyin capsule factory produces about 150000 capsules per year. In addition, there are other tire factories that produce their own products.

 

development trend

 

As we all know, the tire industry is an important pillar industry of the national economy closely related to the automobile industry. At present, the number of existing cars at home and abroad is increasing every year with the improvement of the world economic level, so the tire industry is an industry that will never end. First of all, my country has become the world's largest tire production, consumer, and exporter. With the continuous advancement of tire production technology, the output of various passenger tires, truck tires, engineering tires, and agricultural tires will continue to increase year by year. As a major consumable in the tire production process, the future development of tire curing bladder will increase with the increase of tire production. In terms of specifications and model requirements, with the rapid development of full tempering in the domestic tire industry, various all-steel tire capsules, especially those used for all-steel load, passenger and engineering tires, will surely become the protagonist of market demand. In addition, there are still many domestic tire manufacturers using water tire vulcanization production, these manufacturers using bladder vulcanization transformation has long been the trend; domestic existing traditional water tire vulcanization transformation project will also give birth to a certain amount of capsule demand. According to the comprehensive analysis of the development of related industries, for the future development, it is expected that the domestic annual demand for capsules will maintain an increasing rate of 10% per year.

 

Overview of several production processes

 

As far as the production process of tire vulcanization bladder is concerned, in China, the current capsule production process mainly includes:

 

◆ Single-capsule molding production process

 

The process flow of the single-capsule molding method is as follows:

 

Rubber raw material → rubber mixing → tablet pressing → cutting → mold → mold assembly → vulcanization of vulcanizer → product

 

This kind of production process is produced by a single press mold. The mixed rubber sheet needs to be molded and shaped first, then pressurized and heated for vulcanization. The biggest shortcomings of this process are as follows: firstly, the material is loaded first, then the mold is closed, there is less glue shortage and more running (large flash and uneven thickness), which is difficult to effectively control according to the required process; Secondly, since the film is loaded with air, and butyl rubber has the best air tightness, the entrained gas is difficult to discharge, and the vulcanized capsule must have a large number of bubbles, the capsule compactness is not good, the service life is not high; Furthermore, because it is a single-mode production, which will inevitably make the capsule production cycle is long, laborious, laborious, production efficiency is not high.

 

But this process also has many advantages, such as the process is very mature, easy to achieve industrial production. This process is also the most widely used process in China, but according to the current scientific and technological progress and actual demand situation in the industry, this process is likely to be eliminated.

 

◆ Single capsule injection process

 

This production process is:

 

Rubber raw material → rubber mixing → tableting → cutting → injection to mold molding → vulcanization → product

 

This production process originated in Europe and the United States, the current developed countries and China's Taiwan region are using this method of production. The first four processes of this process are the same as the traditional molding method, except that the rubber injection machine is used for injection molding in the molding process. Compared with the single-capsule molding method, this process eliminates the need for man-made glue, and the injection charge is very uniform. It has the advantages of first clamping the mold, then injecting the material (until the filling is full), no overflow (the clamping pressure is greater than the injection pressure), no bubbles, better quality, and higher production efficiency than the single-capsule molding method.

 

However, the disadvantages of this process are: the injection machine pressure (total pressure 1600 tons) and tonnage are too heavy, the equipment is huge, the factory building is required, and only one capsule can be molded and vulcanized at a time for the integration of the machine and mold. At present, this advanced technology from abroad has also been introduced in a small amount in our country (limited to small capsules), but because the price of the equipment is too high, many companies cannot afford it.

 

◆ Moving mold injection process

 

This production process is:

 

Rubber raw materials → mixing → tableting → cutting → injection to mold molding → transfer mold centralized vulcanization → product

 

This process is the domestic rubber research institute independently developed with independent intellectual property rights to reach the international leading level of production methods. Compared with the single capsule injection process, this production process is a step further. It can realize the shift mold injection, that is, continuous injection production, and higher production efficiency. Its biggest feature is high production efficiency, energy saving and environmental protection (using far infrared vulcanization, eliminating the boiler). In terms of investment, compared with the annual output of the same tire capsule, the process has no boiler investment and has a greater price advantage than imported injection machine projects.

 

It is reported that at present, many domestic manufacturers have the intention to invest in the new tire vulcanization bladder project, which is undoubtedly of great positive significance to the prosperity of the tire market and the development of the rubber industry. But in the process of investment or actual operation, should our investors and operators give priority to the investment of advanced technology and brand operation! (end)