Refractory sheet

Refractory sheet

Refractory sheets are made from a combination of several materials (depending on the type of sheet) and they can be among the most widely used products among refractory materials, especially in power plants and petrochemical industries. These sheets are used in various fields of industry and often as thermal insulation as well as in the production of washers, which in addition to being fast, are also among the least expensive tools. Refractory sheets are placed as a physical barrier between two parts of a set that can cause leakage, and by sealing it, prevent fluids from escaping. Refractory sheets are also used to control the pressure between two pieces under pressure.

The strength of refractory sheets varies mechanically and depends on the materials used in it, but generally refractory sheets are able to withstand temperatures between 300 and 1400 degrees.

The main use of refractory sheets is to prevent the passage of material, which is often in the form of liquid, between two pieces that are connected to each other. This requires filling all the empty parts between the two pieces with refractory sheet or gasket made of it. Therefore, the strength and at the same time the flexibility of the metal sheets must be proportional to the available temperature and pressure so that the sealing is done in the best possible way.

The importance of filling all the gaps between the parts becomes more apparent when we use flanges and the washers used must completely prevent liquids from leaking out. In general, the use of refractory sheets should be done with the following in mind:

Possibility of surface shocks and, as a result, creating distance between two pieces
Defects on the part that lead to the two parts not being fastened
Non-parallel flanges
There is a groove on the surface of the piece

As mentioned earlier, the main application of refractory sheets is in the field of manufacturing and production of gaskets. And the simplest form of washer is the annular washer that is produced to fill the empty space between two parts and to seal it. But more complex washers are also made for use in a variety of industries, including the transportation industry, with physical compositions tailored to the needs of these industries.

Washers are usually made of strong yet flexible materials that are insulated against heat, acids as well as chemicals. One of the facts about washers is that they say, "The longer the pressure on the washer, the longer it will last." Therefore, the materials used in the washers must be such that in addition to being insulated against high temperatures, they can also withstand pressure.

Given the above, it is not surprising that the design of the washers is so important that all the details, large and small, must be clarified for the designer. Because the size, location of cavities, depressions and physical appearance of parts, has a direct impact on the dimensions and thickness of the washer, which must be considered in all respects, using the appropriate materials (according to the temperature and pressure). However, it can be acknowledged that the design of each washer is unique and failure to pay attention to detail in its design can lead to irreparable damage.

Asbestos has long been one of the main materials used in refractory sheets. Although as long as humans do not have direct contact with this toxic element, its use will not be a problem, but due to the awareness of the international community about the known dangers of asbestos for human health and increasing attention to this point, today suitable alternatives such as fiberglass, Ceramics and carbon have been considered for the production of refractory sheets, and efforts have been made to avoid the use of asbestos in the production of sheets that are in close contact with people as much as possible. As a result, asbestos is widely used in the production of refractory sheets for refineries and power plants due to the special properties that we will discuss below.

Refractory sheets are available in different types in the market today, depending on their needs and applications. The general grouping of these sheets is as follows; However, each of these is divided into other subcategories:

Klingrit refractory sheet; This type of refractory sheet, which is named after the famous Klinger company, is the most popular refractory product among various industries. The use of different rubber resins makes this type of refractory sheet suitable for flexibility. And the presence of asbestos in this type of refractory sheets has brought high thermal power and desired sealing for it. Klingrit refractory sheets come in four products:
Wireless klingerite refractory sheet
Wireless klingerite refractory sheet
Wired graphite graphite refractory sheet
Wireless graphite graphite refractory sheet
Asbestos refractory sheet; As the name implies, the main material of this type of refractory sheets is asbestos fibers. Asbestos refractory sheets are the oldest type of sheets on the market that are often used in motorhomes. Outstanding features of this type of refractory sheets include high flexibility, high heat tolerance (up to 700 degrees), resistance to abrasion and tension, as well as good mechanical capability.
Victorian sheet; This type of refractory sheet is mostly used in the automotive industry. The presence of cellulose fibers with suitable density has caused special properties in this product; Including low price, high resistance to burns and hot oil, etc. But one of the most important strengths of this type of refractory sheets is the lack of asbestos in it and therefore environmental friendliness.
Graphite sheet; The purity of graphite powder used in this product reaches more than 90%. Although The high content of graphite makes graphite refractory sheets brittle, but the lightness of this product, its resistance to gases and most rays, still makes it one of the most popular options in the petrochemical industry and power plants.
Dunite sheet; This product is the latest generation of refractory sheets on the market, which is made of two layers of asbestos, along with layers of metals and steel. High pressure tolerance in this product, compared to other types of refractory sheets, has made it the most suitable choice of power plants and oil rigs, as insulation as well as the production of pressure washers.