Conveyor Idler seals are used to keep substances such as grease and lubricant in, while keeping dirt, fluids, and other contaminants out. One advantage to this type of seal is that when small amounts of leakage occur across the seal, as is inevitable, contaminants from the outside still can't get all the way inside, and the materials being sealed may not make their way all the way to the other end. This minimizes fouling caused by mixing of contaminants and sealed fluids.
The Labyrinth Seal has a number of grooves which interlock with other grooves or teeth. This differs from most traditional seals, which use a single lip in an attempt to seal an opening. With the labyrinth seal, each groove acts as its own lip, distributing pressure across the seal rather than concentrating it in one area. While a labyrinth seal cannot deal with high pressure differentials, it can be used in many other types of environments.
Two of the most important things that must be accomplished in order to extend bearing life is to keep lubrication in, and contamination out. That`s the important function of a seal. There are many types of seals that can serve various functions.
Labyrinth Seal,Idler Roller Labyrinth Seal,Conveyor Roller Labyrinth Seal Shandong Xinkaite Bearing Co., Ltd. , http://www.conveyorbearing.com
"White pollution" was once widespread in our country. Disposable plastic lunch boxes and other plastic products were considered the culprit. To this end, in 1999, the former State Economic and Trade Commission No. 6 Order promulgated the “Catalogue of Eliminating Outdated Production Capabilities, Processes, and Products†(the first batch), requiring that disposable foam plastic tableware be eliminated nationwide before the end of 2000, and We hope to promote the production, use and sales of biodegradable tableware. In the next two or three years, the relevant state ministries and commissions and all parts of the country have successively promulgated the “whitening order†to require the elimination of disposable foam plastic tableware within a limited period and promote the use of environmentally friendly products. During this period, AQSIQ issued a "General Technical Specifications for Degradable Catering Products" (GB 18006.1-1999) to regulate the market of degradable plastic products.
However, according to the reporter's understanding, because the price of biodegradable plastic products is too high compared with ordinary plastic products, the domestic market for plastic products such as disposable plastic lunch boxes has not brought more business opportunities for the rapid development of biodegradable plastic products. At the same time, under the national ordinance, disposable foam plastic lunch boxes and some poor-quality toxic non-foam plastic lunch boxes are still sold in the market and are difficult to extinguish. Facts have proved that if it is limited to the uniqueness of biodegradable plastic lunch boxes, it is still unable to meet the needs of a strong consumer market.
It is understood that in 1999, the “General Technical Conditions for Disposable Degradable Tableware†was established on the basis of industry and product at the time, and its scope of application was determined as a one-time degradable tableware, and the disposable degradable tableware was divided into There are five types of light-biodegradable, pulp molded, cardboard coated, vegetable fiber molded, and edible powder molded. Weng Yunxuan believes that this scope of application and classification methods, along with changes in production technology and use requirements, have not met the technical requirements for disposable tableware in the current market, and because the standard name is only degradable tableware, it cannot be applied. For non-degradable traditional plastic tableware, the standard appears to be lagging behind.
Weng Yunxuan said that at present, most disposable tableware are still made of non-degradable plastic on the domestic market. However, he also stated that after many years of development, degradable plastics have gradually been accepted by people and are in the stage of promotion from pilot-to-application. According to reports, taking into account factors such as investment in previous years and depreciation of fixed assets, there are already many degradable plastic product companies that have achieved a certain output value, and about 20% of enterprises have obtained greater profits, which is worthy of recognition. Results. The reporter learned from Wuhan Huali Environmental Protection Technology Co., Ltd. that as a manufacturer of fully biodegradable bio-plastics and products, the company received a US$ 13.5 million venture capital investment from the US-based Detong Capital Investment Co., Ltd. The investor believes that the urgency of China's development of the degradable plastics industry Stronger than abroad, the Chinese market has a very broad prospect.
It is understood that the newly implemented plastic disposable tableware national standard is primarily emphasized on the safety, hygiene and performance of plastic disposable tableware, followed by the degradable properties of plastics. The safety and health performance of the standard is mandatory, and the performance, physical and mechanical properties, and degradation performance are recommended items. Weng Yunxuan believes that because disposable tableware is difficult to recycle and reuse, most of its use is after landfill, incineration and other treatments, so starting from the protection of the environment, the standard provides that if the product is declared degradable, its degradation performance should reach biodegradation. Performance requirements. It is reported that the standards stipulate the biodegradability, and it is also hoped that when the conditions for the development of the degradable plastics industry are ripe, disposable tableware that cannot be recycled easily can be made from biodegradable plastics, thus burying “foreshadowing†for the long-term development of biodegradable plastic products. .
The reporter learned from the Climate Division of the National Development and Reform Commission that in recent years, China has been actively promoting the reduction, reuse, and recycling of resources. In 2008 alone, 16 million tons of plastics were recycled, and the recycling prospects of waste plastics are promising. Weng Yunxuan said that as with traditional plastics, degradable plastics are high-molecular materials that do not degrade in normal use environments and can be degraded under certain environmental conditions after being discarded. Therefore, degradable plastics can be recycled and reused just like traditional plastics. This not only solves the problem of environmental pollution, but also partially solves the energy shortage problem and contributes to the development of a low-carbon economy.
Degradable plastic products are not inhibited by the new national standard
From December 1, the new national standard for "General technical requirements for plastic disposable tableware" began to be implemented. The AQSIQ stated that non-degradable tableware such as disposable plastic lunch boxes that have not been approved for a long time will have a legal status. Then, after the implementation of the national standard, will the ascendant biodegradable plastics industry be inhibited? As the main drafter of the standard, Weng Yunxuan, secretary general of the Degradable Plastics Specialty Committee of the China Plastics Processing Industry Association, stated that the degradable plastics are in a sound stage of development from the pilot application to the popularization and application of the national standard for degradable plastic products. It will only promote rather than suppress it.