◎ Yang Honghui

As the journalist learned, China’s tire output accounted for nearly 40% of the total global tire output, disappearance of demographic dividend resulted in recruitment difficulty of domestic tire enterprises at present, and few people were willing to take the dirty, heavy and exhausting posts even with high salary, in the large environment where the requirements of environmental protection, safety and product quality were constantly increased, the production cost of the tire enterprises constantly increased and the competitive advantage constantly weakened, the enterprises were forced to increase their requirements for equipment. Therefore, how the rubber machinery enterprises satisfy the demand of tire industry for transformation and upgrading and develop safer, more efficient, more eco-friendly and more intelligent high-end equipment became a focus of tire and rubber machinery industry.

Successful Exploration of Improvement of Tire Equipment

“Development of tire industry can’t do without rubber machinery. In a sense, rubber machinery provides powerful support for development of tire industry.” Du Yunfeng, deputy general manager of Shandong Fengyuan Tire Manufacturing Co., Ltd., expressed, over the past few decades, rubber machinery enterprises constantly communicated and cooperated with tire enterprises to crash numerous sparks of technological innovation. He listed over 40 successful explorations in the aspects such as mixing, parts, cutting, building, vulcanization, testing, post treatment process and utilities.

As for the mixing process, in the aspect of solution of efficiency, the mixer developed from two-edge rotor to multi-edge rotor, from low speed to high speed and from small volume to large volume; in the aspect of quality, the mixer developed from shearing-type rotor to meshing-type rotor, thus improving the mixing quality of the rubber materials; in the aspect of solution of processing of silica rubber materials, the mixer developed from general mixer to series mixer; in the aspect of solution of carbon black pollution, transformation from paper bag unpacking to fibc bag pneumatic and from artificial feeding to automatic feeding by auxiliary machinery thoroughly changed the pollution environment of the mixing workshop; in the aspect of solution of labor intensity, it developed from automatic rubber rolling and stirring of the mixing mill to vacuum-assisted rubber movement, to automatic stacking and conveying of rubber sheets and to automatic sampling and conveying of rubber compounds; in the aspect of solution of smoke pollution, the eco-friendly treatment devices of various principles such as catalytic oxidation, absorption pyrolysis and plasma photolysis had been applied widely; in the aspect of solution of intelligent logistics, many enterprises had applied AGV rubber compound conveyance, stereoscopic warehouse of rubber sheet, mixing MES system, etc.; in the aspect of solution of comprehensive resource optimization, low-temperature one-off mixing system was developed to sharply lower the energy consumption, labor consumption, land occupation, logistics and management difficulty of the factories and improve the product quality.

As for part process, in the aspect of solution of composition of rubber material parts, change from external composition to internal composition and from two-composition extruder to five-composition extruder greatly improved the composition efficiency and quality; in the aspect of composition of rubber core steel rim, change from cool fitting to hot fitting and from triangle adhesive vertical fitting to triangle adhesive horizontal fitting solved the problems of raised joint of triangle adhesive and uneven local quality and improved the even movement parameter of the tire; in the aspect of twining of bead ring, it changed from single ring to double rings and six rings and from square section to hexagon section; in the aspect of testing of pressed shape, it changed from tape, calliper and thickness gauge to laser automatic measuring system of section shape; in the aspect of solving unstable contraction of part length, it changed from cutting contraction of single piece to contraction of large roll; in the aspect of calendering and material change of steel wire, translation transposition spindle frame was developed; electron irradiation prevulcanization device solved the reliance of tension of rubber material on thickness and improved the size stability and quality of the parts.

As for cutting and building process, cutting of carcass changed from artificial jointing to automatic jointing and the jointing of carcass changed from automatic overlap jointing to automatic docking, thus solving the problems that overlap jointing of carcass affected dynamic balance, evenness and local dent; extended anti-package rod solved the problem of uneven tire side stretch of mechanical tire building drum; one-off unmanned building machine, auto-matic bar code sticking device, etc. improved the building efficiency; in the aspect of building run-flat tire, one-off and two-off special building machines were developed.

As for vulcanization, testing and post treatment process, hydraulic reform of mechanical vulcanizing machine was carried out, and hydraulic vulcanizing machine was used to replace the mechanical vulcanizing machine, thus solving the problem of segmented mold operation protection and production efficiency; nitrogen vulcanization was used to solve the problem of energy consumption of hot water vulcanization; tire billet EMS automatic vehicle and automatic stereoscopic storehouse solved the logistics strength and land occupation problem of the tire billet; pore-free mold and steel rim sidewall integration solved the problem of rubber trimming and tire foetal hair; finished product testing line solved the problems such as treatment and circulation after tire vulcanization.

As for utilities, development from membrane nitrogen generation and PSA nitrogen generation to copious cooling nitrogen generation greatly saved the consumption of power energy; development of air compressor from piston compressor and screw compressor to large centrifugal compressor improved the efficiency; in addition, application of LED lighting, hot water-type lithium bromide refrigeration units, water jet propulsion cooling tower and unpowered vacuum-pumping system all had a good result of energy conservation.

Du Yunfeng expressed that all the technical progress of tire equipment were successful explorations that China’s rubber machinery industry derives from demand and serve demand and promoted rapid development of China’s tire industry.

What Kind of Equipment Does Tire Industry Need

Sun Huaijian expressed that at present, the tire manufacturing equipment level of China was greatly improved compared with that in the past, however, the equipments in use were still in urgent need of improvement.

For example, raw material handling, internal transportation, weighing, storage and first-in first-out system; few-person and unmanned production equipment of mix-ing workshop; manufacturing accuracy (especially semi-steel tire production equipment) and production efficiency of part production equipment of preparation workshop; production efficiency and manufacturing accuracy of equipment in building workshop; tire billet conveyance efficiency and accuracy of tire billet into the molds in the vulcanization workshop, low-energy consumption vulcanization mode, few-person and unmanned operation of transportation, cutting, quality inspection, specification sorting and warehousing of finished tires; few-person and unmanned operation of delivery sorting and labeling (packaging) of finished tires and packaging and loading of inner tire mat belt of all-steel tires, etc. In addition, efficient treatment of odor during tire production, energy-saving, low-energy consumption and high-efficiency dust removing equipment, accurate and efficient control system of tire production process management (material flowing), etc.

Du Yunfeng listed over 30 items to be specifically improved.

For example, the problem of roller sticking by silica rubber materials during the mixing process, now over 100 shares of silica have been added into the tire compound, the existing method can not thoroughly solve it, why is it sticky? What is the mechanism? If this problem is not solved, there will be many problems during the further application of a large amount of silica; dust drawing of mixer, smoke emission of open mill and reduced air volume for rubber cooling and drying, now the smoke volume is large, which was pumped out directly before, now the environmental protection requirements are strict, the enterprises must introduce smoke treatment devices and need to add a large amount of fans, which will simultaneously increase much energy consumption, such method of environmental protection which increases the energy consumption is contradictory, how can we better solve it in a balanced way?

In the part process, now the extruder is a large heating in the workshop, which heats both in the winter and the summer, a large amount of heat emitted by the extruder makes the part workshop a place hotter than the vulcanization workshop, how to keep warm and how to utilize the heat energy of the extruder? It is worthy of thinking by the rubber machinery enterprises. Every factory has the recycling problem of rubber of inside liner sticking on the cloth liner, which not only causes waste, but also affects the quality; as for automatic jointing problem of triangle adhesive vertical fitting, although horizontal fitting is praised highly now, a large amount of vertical fitting is still the mainstream, this post can not retain the talents, a little joint seems to be obscure, no one can tolerate if artificially jointing for over 1,000 times in one shift, can we make the existing vertical fitting realize automatic jointing? It is the problem of the starting point of automatic rolling and length fixing, to be intelligent, we shall make the single master realize automation, and realize automatic feeding, however, the existing rubber sheet and materials only realize automatic logistics, the rubber sheet is still delivered to the site, with artificial feeding and jointing required, only by realizing the whole set of automation can true intelligenization be realized.

The problems such as asymmetry and extension of back bag of reverse package of mechanical tire building drum, too large carcass joint, slow RFT building, automatic extraction and feeding of feeding trolley, automatic material change of building machine, defect detection of cutting and rolling, automatic head and tail control and automatic length fixing of rolling trolley in cutting and building process as well as undischarged gas from low-profile tire vulcanization, front change of movable block, automatic blowing and sweeping checking device of molds, capsule automatic separator painting device, automatic centering of vulcanization manipulator, assembling and testing mode and automatic replacement of vulcanization molds during vulcanization process are in urgent need of improvement at present.

Intelligent inspection of tire appearance is the post requiring the most persons in tire factory, taking the production line with an annual output of 10 million units of semi-steel tires as an example, such post can not do without 70 persons, and even more persons are required, with large data support, automatic testing can be completely realized in this aspect. In addition, as for cleaning and packaging of tires, the existing equipment can not do it well, which also needs to be resolved immediately.

In the aspect of utilities, small-size unitizing and efficient collection of smoke collection and treatment system of tire factory are also urgent problems. Now a large cover is used to extract the smoke in the workshop, which is not a good and long-standing method.

In addition, there is the problem of integration of multiple information-based systems. Now the tire factory has many information-based systems, ERP, PLM, MES, APS, WMS, BMP, CRM…Although all of them are useful, many functions are repeated. Can we integrate them to build a platform-level “overall M”, “overall system” to reduce the cost for the tire factories and thoroughly get through various information channels in the factory, it is worthy of expectation of the tire enterprises. Du Yunfeng thought, the next upgrading reform of tire machinery was “intelligentization + systemization”. The so-called intelligentization is integration of automatic + information-based system; and the systemization is: process integration + logistics integration + information-based integration + maintenance integration + environmental protection integration + safety integration + cultural ecology integration. In the future, the rubber machinery enterprises will sell the equipment aggregate instead of the equipment, which is what the tire factories hope to see after development from stand-alone development phase to system development phase. Shi Yifeng, secretary general of China Rubber Industry Association Tire Branch, also required the equipment enterprises to brainstorm in equipment manufacturing, lower the energy consumption of the equipment and improve the single-machine efficiency and manufacturing accuracy. “how deep we understand the traditional process equipment and how accurately we transform them determine how far we will go in the future.”

Du Yunfeng expressed that now the tire and rubber machinery industries developed from open innovation to independent innovation, we should not always follow the others, but should make more efforts to change from following to running together and then leading, thus realizing the power dream of rubber industry.