The Knowledge of Install Gasket on Pipe Flanges or Steel Flanges

Jinan Hyupshin Flanges Co., Ltd provide knowledge of install gasket on pipe flanges. We are steel flanges manufacturer from China, supply all kinds and steel of pipe flanges, buy flanges contact us, sale@hyupshin.cn.

Select flange gasket media, temperature, pressure and working conditions should be important factors. For example, if the working pressure is not high and the plastic flange is used for butt joints (PN<6kg), the use of harder seals, such as F4 or metal materials, can lead to leakage due to improper material selection. Graphite materials and non-asbestos materials will achieve better results due to flexible effects, and vice versa.

For another example, in the working environment of chemical media, it is necessary to reasonably match different sealing media to achieve good results, otherwise unpredictable chemical changes can easily occur. Therefore, any flaws in the selection of seals can lead to unimaginable consequences.

The general gasket structure has the following types for reference:

1. Mostly used for flange joints are: a. Flat washers: material is made of medium-pressure asbestos, Pilot non-asbestos, oil-resistant asbestos, PTFE, graphite gasket or reinforced graphite gasket, metal flat gasket, special metal Gaskets, etc.

b. Wound gasket: with outer ring or with inner and outer ring (convex flat flange multi-purpose); with inner ring (convex flange commonly used); basic type (without inner and outer ring), slot-type flange special The sealing surface is narrow and flat-welded on a full-faced flange. The sealing surface is wider, equivalent to a wound gasket with inner and outer rings. It must be noted which standard the flange is.

2, used to rotate the shaft seal with a variety of fillers. Such as flexible graphite ring (open and not open), various materials braided packing (or packing ring), various materials inside and outside the skeleton oil seal YX ring and O-ring and so on.

3, for special parts of the sealed product. Commonly there are various sealing strips, PTFE ball valve seats, graphite rings and rubber parts butterfly valve rings, etc.
What should you watch out for when installing seals?

1. Do not damage the sealing surface of the seal surface or the sealing performance of the sealing line plane seal depends on the upper and lower two end surfaces; the sealing performance of the hydraulic seal depends on the lip line associated with the hole or the shaft. These parts are both soft and It is made of special materials, such as graphite, rubber, and fiber, which are resistant to heat, corrosion, and aging, and are vulnerable to damage. Therefore, they need special protection and care during handling, installation, and storage. Once damaged, they are often damaged. Will leave a lot of hidden dangers to the sealed parts;

2, can not be forced to install some seals are placed in the groove of the stuffing box, then need to be tightly fitted, construction can not be rough, barbaric, the action of a strong force will inevitably destroy the original prefabricated seal structure, which is like Impregnating the precast concrete and filling it in the required parts inevitably leads to disaster. The installation of such seals must be very careful and careful, and the insertion must be carried out step by step.

3. When installing, it is necessary to pay attention to the balance and symmetrically place the seal on the position just close to the effective sealing surface (or lip line). After the system is opened and used, further observation and tightening of the seal must be done to prevent the occurrence of micro-leakage due to changes in working conditions (such as pressurization) during system operation.

How to properly keep temporarily unused seals?

1. Anti-aging, light-proof, moisture-proof, flat, and away from cold and heat sources;

2. Do not apply pressure to maintain the natural relaxed state of the seal, and change its physical shape without applying external force;

3, classification mark (the same shape, different materials, use parts, applicable standards, stock date, etc.

Flange Usage Classification and Rating Choose

Flange (flange), also known as flange or flange. Parts that connect pipe to pipe. Connect to tube end. There are holes in the flange, you can wear bolts, so that the two flanges closely linked. Flange sealed with gasket. Flanged pipe fittings (flanged pipe fittings) refers to the flange (flange or plate) of the pipe. It can be cast (not available), but also by screwing or welding. Flange coupling (flange, joint) by a pair of flanges, a gasket and a number of bolt nut composition. Gasket on the flange between the two flanges, tighten the nut, the gasket surface than the pressure reaches a certain value after deformation, and fill the sealing surface uneven, so that the connection tight leakage. Flange connection is a detachable connection. According to the connected components can be divided into container flange and pipe flange. Divided by the structure type, there is a whole flange, flange and threaded flange flange. Common flange flange welding and flange welding. Welded flat flange less rigid, suitable for pressure p ≤ 4MPa occasions; also known as flange welded flange, more rigid, suitable for high pressure and temperature applications. There are three types of flange sealing surface: flat sealing surface, suitable for low pressure, medium non-toxic occasions; concave and convex sealing surface, suitable for slightly higher pressure occasions; tongue and groove sealing surface, suitable for flammable and explosive , Toxic media and high pressure occasions. Gasket is a ring that produces plastic deformation and has a certain strength of the material. Most of the gaskets are cut from non-metal plates, or made by the professional factory according to the required size. The materials are asbestos rubber plates, asbestos plates, polyethylene plates, etc .; also thin asbestos (white metal, stainless steel) And other non-metallic materials wrapped up made of metal pads; there is a thin strip of steel and asbestos with winding wound gasket. Ordinary rubber gasket for temperatures below 120 ℃ occasions; asbestos rubber gasket for water vapor temperature of less than 450 ℃, the oil temperature is less than 350 ℃, the pressure is less than 5MPa occasions, the general corrosion Medium, the most commonly used acid asbestos board. In high-pressure equipment and piping, the use of copper, aluminum, 10 steel, stainless steel lens or other shapes made of metal gasket. High-pressure gaskets and sealing surface contact width is very narrow (line contact), sealing surface and gasket processing finish higher. Flange sub-threaded connection (silk) flange and welding flange. Low pressure small diameter wire flange, high pressure and low pressure large diameter welding flange are used, the pressure of the flange thickness and connecting bolt diameter and the number is different. Hyupshin Flanges supply all steel flanges forging pipe flanges when you choose and buy flanges contact us, sale@hyupshin.cn.

The difference between the new insulating flange and the old-fashioned insulating flange

Introduction: With the popularization of gas, the construction and protection of gas pipeline engineering is very important. The supporting equipment also includes insulating flanges. Like insulating joints, insulating flanges are products for the petroleum and chemical industries.

The difference between the new insulating flange and the old-fashioned insulating flangeWith the popularization of gas, the construction and protection of gas pipeline engineering is very important. The supporting equipment also includes insulating flanges. Like insulating joints, insulating flanges are products produced for the petroleum and chemical industries.

The insulating flange has a simple structure and is safe to use. However, the insulating flange also has the difference between the old-fashioned insulating flange and the new insulating flange. The industrially developed advantages are the reduction of the production cost and the improvement of the product quality. Comparison of new and old versions of insulating flanges can better illustrate this point.

Vintage insulating flange

The composition of the old-fashioned insulating flange: between the two butt-welding plane flanges, flange insulating gaskets are installed, and insulating sleeves and insulating bolt gaskets are added to the fastening bolts. Its flange insulation gasket material is made of oil-resistant rubber asbestos board, neoprene rubber board, fabric base neoprene rubber board and PTFE material. Insulation bolt sleeves and bolt insulation gaskets are made of high-strength phenolic laminates and cloth tubes. Its characteristics are: good steel, stable insulation properties, need a special installation location dedicated installation, high cost.

New insulating flange

Appropriate improvements have been made to the structure of old insulating flanges. In the city gas transmission and distribution project, the pressure of the city gas transmission and distribution project is low (PN ≤ 2.5MPa) and the pipe network pressure PN ≤ 0.4MPa is improved. In the pipe network transmission and distribution project, steel flat flanges are used instead of butt welding plane flanges, flange insulation gaskets are made of PTFE, oil-resistant rubber asbestos pieces, neoprene rubber, etc., and the fastening bolts are insulated. The sleeve and the insulation pad will be two, and half of the insulation sleeve will be shortened to make an integral high-strength insulation sleeve. It not only saves the engineering cost, but also saves the on-site installation position. It is a simple and applicable new type of insulating flange, and the construction cost is particularly low.