China Conveyor Belt

Good graphite is dense to the naked eye. The materials of the end face seal friction pair. The resin-impregnated graphite has good corrosion resistance, but not high temperature resistance (temperature resistance is about 170~200℃); the impregnated metal graphite has good high temperature resistance (the high temperature resistance of bronze, aluminum, lead, etc.

Tungsten carbide alloy The metal carbides with high hardness and high melting point, such as tungsten carbide and titanium carbide, are pressed and sintered by powder metallurgy with a binder. Impregnated graphite can be divided into two types: resin impregnated and impregnated metal. Tungsten carbide is the most widely used end face seal material, and seal seamless belt is mostly used as a static ring for medium and low speed mechanical seals and a moving ring for high-speed mechanical seals.

The material of the auxiliary sealing ring. The advantages are high hardness and strength, wear resistance, high temperature resistance, corrosion resistance, low linear expansion coefficient, and the disadvantages are brittleness and difficult processing. It is used as a moving ring for medium and low speed mechanical seals and a static ring for high-speed mechanical seals.

The sealing performance and service life of the mechanical seal are related to the materials of each part, especially the material of the end face seal (friction pair), the material of the auxiliary seal and the material of the spring. Most applications are alumina ceramics and cermets. Graphite is the most widely used non-metallic material. Ceramics are mostly used in corrosive media, medium and low speed occasions. can reach 400~500℃), but the corrosion resistance is poor .

Surfacing hard alloy hard alloy surfacing welding hard alloy on the sealing surface of carbon steel, chromium steel and chromium nickel steel, the advantages are high hardness, good wear resistance, good temperature resistance (below 500 ℃), corrosion resistance or Good cavitation, the disadvantage is that it is easy to produce pores, slag inclusion and uneven surface hardness. The disadvantages are brittleness and high hardness that are difficult to process.

There are many types of mechanical seals for pumps, with different models, but there are mainly five leakage points: Seal between shaft sleeve and shaft;  Seal between moving ring and shaft sleeve;  Seal between moving and static rings ;  The seal between the static ring and the static ring seat; The seal between the sealing end cover and the pump body.

The above phenomenon often occurs during trial operation, and sometimes it can be eliminated by appropriately adjusting the static ring seat, but most of them need to be re-disassembled and replaced. If there is no significant change in the leakage, there is a problem with the static and dynamic ring seals; if there is a significant change in the leakage during cranking, it can be concluded that it is a dynamic,

There are problems with the static ring friction pair; if the leakage medium is sprayed along the axial direction, there are mostly problems with the moving ring seal. In addition, leakage channels can also exist at the same time, but there are generally primary and secondary differences. If the amount of leakage is small, there is usually a problem with the moving or static ring sealing ring; when the amount of leakage is large, it indicates that there is a problem between the moving and static ring friction pairs. Leaks occurred during trial operation.

If the leakage medium is sprayed around or leaks from the water cooling hole, the static ring seal is mostly ineffective. Leakage during installation static test After the mechanical seal is installed and debugged, a static test is generally required to observe the leakage., a large axial force is caused to separate the contact surfaces of the dynamic and static rings; Pair installation When the mechanical seal is too large, the end face of the friction pair will be severely worn and scratched;

On the basis of preliminary observation of the leakage and PTFE adhesive tape judgment of the leakage location, the manual cranking observation is performed. Therefore, the mechanical seal leakage during the trial operation is basically caused by the damage of the dynamic and static ring friction pairs after the failure of the shaft and the end cover seal is eliminated. 1. The main factors that cause the failure of the friction pair seal are: (l) During operation, due to abnormal phenomena such as evacuation, cavitation, pressure holding, etc. As long as you observe carefully and are familiar with the structure, you will be able to make a correct judgment. After the mechanical seal for the pump has undergone static testing, the centrifugal force generated by the high-speed rotation during operation will inhibit the leakage of the medium.

A thicker coating can be obtained by one coating, for example, a coating of 100-300 m; with a common solvent coating, about 4-6 times are required , And the thickness can be achieved in one pass with powder coating. The working process is as follows: the compressed air is passed into the container below the partition, and the compressed air passes through the porous partition to suspend the powder PTFE coated fiberglass tape on the upper part without the effect of air flow, and rolls over in the upper container, showing 'boiling'.

Powder coatings began to be used in protection and electrical aspects. The porous partition divides the container into upper and lower parts. In addition to thermosetting epoxy, polyester, acrylic, there are still a large number of thermoplastic grease resistant powder coatings, such as polyethylene, polypropylene, polystyrene, fluorinated polyether, nylon, polycarbonate and various Fluorine resin, etc.. The preheating temperature of the workpiece can be slightly higher than the melting temperature of the powder. ;status.

The powder coating does not contain solvents and has no pollution from three wastes, which improves labor and hygiene conditions. It has been widely used up to now. Introduction to powder spraying and powder spraying equipment (1) Powder spraying process Powder spraying, also called powder coating, is a new type of coating process that has developed rapidly in recent decades. New technology such as powder electrostatic spraying, high efficiency, suitable for automatic assembly line coating, high powder utilization, and recyclable. Our country has started the experimental research of powder coating since the 1960s and has been applied in production.

The powder coating process has many outstanding advantages: Some countries started research experiments as early as the 1940s, but progress was slow. Surface coating. In 1954, James of Germany successfully coated polyethylene with the fluidized bed method. In 1962, the French company Symes company invented powder electrostatic spraying, and powder coating began to be officially adopted in production.Spraying generally includes: spraying (plastic) powder and painting (paint). With the development of technology, it has been widely used in the automotive industry, electrical insulation, corrosion-resistant chemical pumps, valves, cylinders, pipes, outdoor steel components, steel furniture, castings, etc.

The corrosion resistance of the coating is very good.  In recent years, due to the environmental protection of various countries The importance of protection, powder coatings that do not pollute water and atmosphere, have been developed rapidly. It is composed of a porous partition and a container. Powder coating process .

The disadvantages of this method are:

① The dimensional stability of PTFE is poor at high temperature and it is difficult to maintain its shape;

② The bonding force between the filler and the PTFE matrix is ​​small, which affects the highest bonding strength. The results of the study showed that the bonding strength of PTFE before and after treatment was increased from 7.

The advantages of this method are:

① Good weather resistance, humidity and heat resistance;

② Suitable for long-term outdoor use.The high temperature melting modification method is to sinter some fillers with strong surface activity, easy adhesion and small particle size (such as silica, aluminum powder, etc.

Based on the high-temperature melting method, Fu Zhaoxia and others added an inorganic additive LW to PTFE, which effectively improved the bonding performance of the PTFE sheet.

Guo Jinyan and others used silane coupling agent to improve the melting method.) to the surface of PTFE under high temperature conditions to change the structure of the PTFE surface And properties to achieve the purpose of improving bonding ptfe film adhesive tape strength.8 MPa to 9.

When LW is surface-treated with a silane coupling agent, the adhesion performance of the PTFE sheet is further improved, and its peel strength and shear strength reach the maximum when w(LW)=10%

Consumers can use Teflon spray equipment with confidence. Appropriately increasing the level of the coating system can enhance the thickness of the coating, thereby significantly improving the wear resistance and scratch resistance of the coating and extending the service life of the pot.

Explanation, one-layer system refers to a non-stick layer composed of a single coating; two-layer system refers to a non-stick layer composed of two coatings: bottom layer and top layer; three-layer system refers to three coatings consisting of bottom layer, middle layer and top layer Constructed non-stick layer.html Teflon coating, Teflon coating,.kytfl.

Make 304PTFE fiberglass adhesive tape stainless steel workbench. Teflon etc. Spraying Teflon. Stainless steel shelves. A spokesperson for the General Administration of Quality Supervision, Inspection # and Quarantine once stated that the quality and safety of non-stick pan products produced by Chinese companies that meet the national mandatory standards are guaranteed. Welcome to patronize! Teflon spray non-stick pan has been widely used in western developed countries.

The company adheres to the business philosophy of 'customer first, forge ahead' and the principle of 'customer first' to provide our customers with quality services. According to the different application functions, Teflon spray non-stick pan products can be divided into boiling pans, frying pans, frying pans, and milk pans; according to the internal and external non-stick coating system, non-stick pans can be divided into a layer system , Two-tier system and three-tier system pot.  Chinese non-stick pans have been popular since the 1990s, and an increasing number of consumers have begun to recognize their functions. Small carts.