In the past, when I mentioned the wheel polishing workshop, the reporterâ€™s impression was that the dust was flying everywhere, the friction was sharp and sharp, and the post operator was busy with thick dust masks. When they passed, the footprints were deeply printed on the dust. Among them.
Recently, a company in Zhejiang Xinchang visited the reporter to completely change the impression of the wheel polishing workshop. In the wheel polishing workshop called Zhejiang Wanfeng Auto Group, the scene is very different from the traditional wheel polishing workshop: the wheel rotates continuously in the huge circular drum, and the jade of the size of the grain is kept smashing. It is like Tai Chi in Chinese martial arts. It is invisible, invisible, and there is no dust in this. The operators are free to shuttle between the rollers, even the masks are not worn.
â€œThis is the automatic polishing production line developed by our company's technology R&D team after hundreds of tests and countless process and prototype verification. It has been officially put into use. Our wheel polishing workshop does not produce suspended dust, fundamentally Eliminate the risk of dust explosion." Zhang Wangang, the person in charge of the polishing workshop of Zhejiang Wanfeng Auto Group, showed pride in the words.
Zhang Jiangang said that the process is water-based automatic polishing. â€œIt fills the gap in the automatic polishing process of domestic wheels and opens the door to technological innovation in the wheel industry.â€ Zhang Coal Steel said.
Remediation efforts -
Safety production situation is still grim
The â€œ8.2â€ accident in Kunshan caused great shocks in the industry. The State Administration of Work Safety has carried out special rectification of dust explosion for three consecutive years, but the safety production situation in the igniting and dusting industry is still grim.
In recent years, there have been many dust explosion accidents in China.
On August 2, 2014, Kunshan Zhongrong Metal Products Co., Ltd. (the sole proprietorship of Taiwanese-owned enterprises) located in Kunshan Economic and Technological Development Zone, Kunshan City, Jiangsu Province, Jiangsu Province, suffered a major aluminum dust explosion accident. 75 people were killed and 185 injured on the day.
This accident caused great shocks in the industry. Shortly after the accident, the State Administration of Work Safety put dust explosion as an important part of the industry and trade industry to prevent serious accidents, and included them in the special rectification tasks of the General Administration in 2014, 2015 and 2016. The whole country has set off a wave of dust explosion-proof special rectification.
However, the safety production situation in the igniting and dusting industry is still grim.
On April 29, 2016, an aluminum dust explosion occurred at the Jingyixing Hardware Processing Factory in Guangming New District, Shenzhen, Guangdong Province. As of May 6, a total of 4 people were killed and 6 were injured, 5 of whom were severely burned. The accident unit is mainly engaged in the polishing business of bicycle aluminum alloy parts. The dust removal system is not set according to the standard specifications. The axial flow fan is used to pass the rectangular brick groove dust removal air passage, and the polished aluminum dust positive pressure is blown to the outdoor sedimentation tank. In the notice issued by the General Office of the State Administration of Safety Supervision on this accident, 10 key problems and hidden dangers in the construction, dust removal system, fire prevention and explosion prevention and dust cleaning found in the special rectification of dust explosion in the industry and trade industry are listed. .
An industry insider who asked not to be named told reporters that the ultimate treatment of wheel surface in China currently includes the following three processes: painting, electroplating and polishing, all of which are inseparable from artificial sanding, grinding and polishing. In the field of wheel hub polishing, the degree of automation is still relatively low, mainly using labor.
The industry insider introduced that the first step of manual polishing, sandblasting, the purpose is to knock off the oxide layer, the dust generated in this process can be automatically discharged; the second step, artificial sandpaper polishing, this process will produce A small amount of dust; the third step, the wheel mechanical mechanical polishing, the most dust generated in this process, the highest level of danger, prone to spontaneous combustion, explosion, and also a great harm to human health.
Dust explosion means that the dust is within the limits of the explosion. When it encounters a heat source (open flame or high temperature), the flame instantaneously propagates through the entire mixed dust space. The chemical reaction speed is extremely fast, and at the same time, a large amount of heat is released, forming a very high temperature and a large Pressure, the energy of the system is converted into mechanical energy as well as light and heat radiation, which has a strong destructive power.
The occurrence of dust explosion generally requires three conditions: First, the flammable dust is suspended in the air at an appropriate concentration to form a dust cloud, which is often said; second, there is sufficient air and oxidant; third, there is a fire source or strong vibration and friction. Explosive dust: metal dust (such as magnesium powder, aluminum powder), coal dust, grain dust (such as wheat flour, starch), feed dust (such as blood meal, fish meal), agricultural and sideline products dust (such as cotton powder, tobacco powder) , forest product dust (such as paper powder, wood powder), synthetic material dust (such as plastic powder, dye powder).
Lu Mingxiang, an expert on safety production in Zhejiang Province, said: "At present, the key to preventing dust explosion is to reduce the dust concentration in the workplace. Generally speaking, it is necessary to ensure the ventilation conditions in the workplace, and at the same time install suction and dust removal equipment to control open flames. Use explosion-proof electrical products."
In addition to being prone to explosions, dust is also very harmful to human health. For example, the polishing process is extremely harmful to the health of the operator. Usually, if the perfect protective measures are not taken, the operator is prone to suffering from silicosis. Some workers joked: As long as you wait for half an hour in the polishing shop, your face will be like a whitening mask, only two eyes are black.
Water as a medium -
Let the dust have no chance to fly
The water-based automatic polishing process does not generate suspended dust during the production process, and directly destroys the conditions of the dust explosion from the source, so that the dust cannot fly. In addition to achieving the most important purpose of â€œmaking safety more secureâ€, production efficiency and product quality have also been greatly improved, and the entire production process is environmentally friendly, safe, stable and beautiful.
How to completely solve the safety problem of the wheel polishing process, not only to ensure production safety but also to obtain higher benefits for enterprises? Zhejiang Wanfeng Auto Group answered this question beautifully.
Xinchang County, Zhejiang Province is the hometown of bearing, textile machinery base, cold distribution county, and auto parts production base. There are 12 enterprises involved in burning and dusting in the county, including 9 metal dust enterprises. Zhejiang Wanfeng Auto Group is a metal dust-related enterprise. The company is Asia's largest production base for aluminum alloy wheel products.
It is reported that starting from 2012, Zhejiang Wanfeng Auto Group will set up a scientific research and development team to carry out the polishing process - automatic polishing technology. The occurrence of the â€œ8.2â€ accident in Kunshan prompted the company to accelerate the pace of technology research and development.
â€œWe have the same product attributes as Kunshan Zhongrong Metal Products Co., Ltd. The severity of the consequences of this explosion is far beyond our expectation.â€ Zhang Coal Steel is the head of the research and development team of Zhejiang Wanfeng Auto Group. He said that he is There was even some anxiety during the period after the â€œ8.2â€ accident in Kunshan.
Zhang Coal and Steel knows the complexity and difficulty of carrying out the polishing process reform. Because before this, the domestic wheel hub field did not have a precedent for automatic polishing research and development, which means that all aspects of technology research and development must start from scratch. After nearly half a year of research and development, in August 2013, the prototype wheel was approved by North American General Motors and Ford, and the product was ordered in volume. The automatic polishing production line was officially put into production.
According to Zhang Coal Steel, the first step of water-based automatic polishing is the grinding and sand-blasting process. The brown corundum abrasive is used for sanding, and the dust is automatically discharged into the water. The second step is the pressure grinding process, which uses different meshes of abrasives. After two to three grinding processes, the surface gloss of the product reaches the polishing standard, and the dust is automatically discharged into the water. The third step is the polishing process, which uses a fine polishing abrasive for water-based grinding and polishing to make the product meet the above standard of sub-mirror. Finally, the dust discharged in the water is treated uniformly to ensure safe production.
â€œThe water-based automatic polishing process does not produce suspended dust in the production process, directly destroying the conditions of dust explosion from the source, so that the dust cannot fly.â€ Cao Jimei, deputy chief engineer of the Zhejiang Academy of Safety Production Science, said that, in principle, This method can be referred to as a wet process.
Water-based automatic polishing, the most important thing is to achieve the purpose of "making safety more secure", while the production efficiency and product quality are greatly improved, the whole production process is environmentally friendly, safe, stable and beautiful.
According to calculations, each machine produces more than 120 regular products per shift. The cost of the entire polishing process is about 52 yuan per piece, which is about 35 yuan less than manual polishing.
â€œWater-based automatic polishing process is the first in the field of domestic wheels.â€ Zhang Coal Steel proudly said. In February 2015, the Zhejiang Provincial Federation of Trade Unions recognized the â€œZhangmei Steel Auto Wheel Polishing Methodâ€ as the advanced operation method of Zhejiang Province. The automatic polishing equipment developed by the Zhang Coal and Steel team won the national invention patent, and the clamping device of the polishing machine was awarded the utility model patent.
Xinghuo Yuanyuan -
Technical transformation process equipment updated into a boom
With a strong sense of safety, the company breaks through the traditional production mode and enhances the intrinsic safety level through â€œmechanized substitution, automation and reductionâ€. The regulatory authorities must continuously promote and guide to further enhance the endogenous power of enterprise safety production.
"The reform of the 'mechanized substitution, automation and reduction' process is not only an inevitable requirement for the transformation and development of the manufacturing industry, but also an inevitable requirement for improving production safety and occupational health." Zhang Shaozhong, director of the Xinchang County Safety Supervision Bureau said.
Today, the county's ignited dust companies have set off a wave of technological transformation and process equipment renewal.
Wanfeng Auto Group has stepped up its efforts in technological transformation and gradually eliminated the manual polishing operation. The goal is to use more than 90% of polishing machinery.
Among other companies, some have taken the initiative to strengthen the applicability of the process, trying to push from the single wheel hub to the entire aluminum product processing industry; some independent research and development and automatic polishing process equipment, to expand the scope of automatic polishing process applications. The person in charge of Zhejiang Hequn Machinery Co., Ltd. told the reporter that the dust wheel polishing production line (series equipment) independently developed by the company has officially entered the market and received favorable comments.
â€œThis shows that the traditional industry has a growing demand for safety.â€ Zhang Shaozhong said, â€œEnterprises break through the traditional production mode with a strong sense of safety, and improve the intrinsic safety level through 'mechanization substitution, automation and reduction of people'. Constantly promote and guide to further enhance the endogenous power of enterprise safety production."
Xinchang County takes the opportunity of carrying out special dust control actions as an opportunity to promote the prevention and control of hidden dust enterprises as a long-term work, and promote the transformation and upgrading of related enterprises to encourage enterprises to adopt new devices, new equipment and new ones. Technology, new technology, urge enterprises to implement safety production responsibility system, and strive to build a long-term mechanism for accident prevention.
Not long ago, the Zhejiang Provincial Administration of Work Safety issued the â€œImplementation Plan for the Prevention of Heavy and Serious Accidents in the Industry and Trade Industryâ€. The implementation plan proposes a number of measures including the implementation of classified supervision, strengthening special rectification, and strengthening technical support. It will promote the application of relevant advanced applicable technologies, equipment and processes, and comprehensively improve the safety and technology level of dust operations, as the province's ignited dust. The goal of the company's three-year special action.
â€œTraditional industries have realized the transformation and upgrading through 'mechanization substitution, automation and reduction of people', and reduced to completely eliminate safety risks, thus reducing production safety accidents. This is a development direction.â€ The relevant person in charge of Zhejiang Safety Supervision Bureau said.
Woofer Bass,Rubber Edge Speaker,Woofer Tweeter,Paper Cone Woofer
Ningbo Sonice Electroacoustic Science and Technology Co., Ltd. , https://www.secspk.com