(VEN) – Doctor of Science Do Quoc Quang and his co-workers at the Research Institute of Technology for Machinery under the Ministry of Industry and Trade have successfully researched and developed a non-asbestos roofing production line. This technology has created a new breakthrough to replace imported non-asbestos roofing pieces and most importantly, protect people’s health and avoid toxic materials.
Ninety-five percent of equipment manufactured domestically
DSc Do Quoc Quang said the biggest difficulty was to find a substitute for asbestos as most of the materials to consolidate cement foundation did not have the specific features like durability and stickiness of asbestos. After studies on some other materials like fiberglass or steel, in the end the research group decided to choose the polyvinyl alcohol synthetic fiber (PVA) to replace asbestos, while adding additives into pulps to increase stickiness. PVA fiber, cement, cellulose pulp, water and additives were mixed to create a suspension mixture. Then, the mixture was brought to a rolling instrument to filter water and pressed into the finished roofing pieces. From here, a non-asbestos production line was successfully constructed with 95 percent of domestically made equipment. The production line consists of two main sets of equipment: one to prepare materials and the other for the rolling stage.
Compared to the asbestos production line, the level of automation of the non-asbestos production line is much higher. More than 2,000 roofing sheets made of a mixture of cement and auxiliary materials were successfully produced by the non-asbestos production line. The test results showed that the flexural durability and water absorption of these roofing pieces were equivalent to the corrugated asbestos – cement of Vietnamese Standard 4434:2000.
Protecting human’s health
According to DSc Do Quoc Quang, the technology to produce domestic non-asbestos roofing pieces does not have significant differences compared to a normal asbestos – cement production line, except for the suspension mixture and speed parameters of the equipment. This is also an opportunity for businesses to switch from the old production method to the new production technology to manufacture non-asbestos roofing pieces.
The new production line is currently being transferred to Tan Thuan Cuong Production and Trade Joint Stock Company (Tu Ky District, Hai Duong Province).
Deputy Director of Tan Thuan Cuong Production and Trade JSC Truong Van Han said the first non-asbestos roofing piece products of the company was supplied to Phu Tho Ceramics Factory and exported to Japan and the Republic of Korea. Currently, many businesses in Vietnam have ordered these products and they have appreciated the product quality and especially their non-asbestos nature.
In addition, the new production line assures safety and health for workers and consumers as well. Previously, when producing the asbestos roofing pieces, workers could face the risk of cancer as asbestos is a very harmful. Therefore, the production and use of non-asbestos roofing pieces has allayed fears of occupational diseases.
By Nguyen Duyen