Production of non asbestos roofing sheets by internal technology

In order to replace asbestos in roofing production, Dr. Do Quoc Quang and colleagues of the Institute of Technology, Ministry of Industry and Trade have studied, successfully developed technology and production lines of non-asbestos roofing sheets.

This line is being transferred to production at a factory in Hai Duong. Dr. Quang hopes to be able to apply his research to the production of other construction materials.

Assert quality

Dr. Quang said the problem for the research team was to find materials to replace asbestos. Because most of the fibers used for reinforcing cement substrates do not have adhesion and durability properties like asbestos fibers.

In the framework of the project under the key National Science and Technology Program on Research, Development and Application of Advanced Technology in the Production of Key Products in the 2006-2010 Period (KC 06 / 06-10) , Dr. Quang and his colleagues have studied many types of fibers such as glass fibers, steel fibers . Finally, the team selected synthetic fibers PVA (polyvinyl alcohol) to replace asbestos. In order to increase the adhesion of cement to PVA fiber in suspension solution, Dr. Quang introduced some additives in pulp.

Since then, a production line of non-asbestos roofing sheets has been successfully fabricated with 95% of equipment manufactured in the country. The line consists of two main equipment assemblies: equipment assembly to prepare materials and equipment for rolling.

Workers of Tan Thuan Cuong Production - Trading Joint Stock Company are operating with new technology lines.

Dr. Quang said that compared with the roofing production line with asbestos, the automation level of the asbestos-free line is much higher. Accordingly, PVA fiber, cement, cellulose pulp, water, additives are mixed in a certain order and volume to form a suspension mixture. Then, this mixture is transferred to the assembly of rolling equipment to separate water, pressed into finished roofing sheets.

More than 2,000 roofing sheets made of cement and auxiliary materials have been successfully produced by non-asbestos chains. Test results show that the flexural strength and water permeability of these roofing sheets are equivalent to asbestos-cement wave sheets, achieving TCVN 4434: 2000.

Replace old technology

One of the goals that Dr. Quang and his colleagues set out in the research topic is to create conditions for existing asbestos-cement roofing production lines to be converted to new technology at the beginning cost. lowest investment.

However, the technology of non-asbestos roofing production has no big difference compared to the production line of asbestos-cement roofing sheet except for the equipment of suspension preparation and the speed parameters of the equipment. This is also an opportunity for enterprises to have the most reasonable direction from the old-style roofing technology to the production of asbestos-free roof sheets.

Currently, non-asbestos production line technology has been transferred to Tan Thuan Cuong Production - Trading Joint Stock Company (Tu Ky, Hai Duong).

Mr. Truong Van Han, deputy director of Tan Thuan Cuong Production - Trading Joint Stock Company, said the company's first non-asbestos roof sheet products were supplied to Phu Tho ceramics factory and exported to other countries. Japan, Korea. Currently, in the country, there are also many units ordering and they all evaluate products of quality and especially without asbestos.

In addition to outstanding features that do not use asbestos, non-asbestos roofing production lines are also reasonably designed, self-contained and highly automated, so they cost less labor.

Moreover, this line also creates peace of mind for employees, ensuring health for users. Mr. Chuong Van Anh, worker of Tan Thuan Cuong Company said: 'The production of asbestos-free roof sheets makes us feel much more comfortable, workers do not have to worry about occupational diseases'.

However, for non asbestos roofing products to be widely used, Dr. Quang and his colleagues are continuing to research and complete equipment lines. He also hopes to be able to apply his research to the production of other construction materials such as tile, partitions, bricks .