2019-08-12 14:29:09 Source: sand dredge pump-slurry pump parts-China Do Pump
What is the dredge pump packing seal?
What is the dredge pump packing seal? The dredge pump packing seal is a kind of shaft seal type of dredge pump. Today, we mainly introduce the origin, characteristics and material composition of the dredge pump packing seal.
dredge pump packing
1. the concept of packing seal
Packing seals, also known as Gland Packings seals, commonly known as packings, packing seals are the oldest type of sealing structure. In ancient Chinese water lifting machines, plugging cotton yarns was used to block them. The first steam engine in the world to live in a leak is also in this form of seal.
The production and development of oil and gas exploration technology in the 19th century has led to new developments in filler-sealed materials.
In the 20th century, packing seals were favored by many industrial sectors because of their relatively simple structure, low price, and wide range of sources.
2. the application of packing seal
Packing seals are mainly used for dynamic sealing of process machines and moving parts of equipment in the mechanical industry, such as centrifugal pumps, compressors, vacuum pumps, mixers, shaft seals and reciprocating pumps for reactors, plungers or piston rods for reciprocating compressors. And the seal between the valve stem of the spiral motion valve and the fixed body.
3. the application of packing seal
The packing seal can be used for high temperature and high pressure, for example, oil-impregnated asbestos packing with a sealing pressure of up to 12 kg/cm and a medium temperature of up to 250 °C.
However, the sealing speed of the packing is low. For example, when used in a water pump, the upper limit of use speed is 6 m/s, because the packing of the packing is not wear-resistant, and the contact friction surface of the packing and the shaft is large, and The packing has a large pressure on the shaft, which causes heat and wear.
If the pressure of the sealing medium is high, the screw 4 must be tightened more tightly so that the pressing force of the packing shaft is larger, so as to ensure that the high-pressure seal does not leak. At this point, the shaft speed must be lowered even lower.
It can be seen that the pressure and the speed are related to each other. When the pressure is low, the speed can be allowed to be higher; if the pressure is higher, the speed must be lowered to meet the requirements of the high pressure seal.
The reason why the packing seal is leaked is that the friction generates a high temperature, and some components in the packing are volatilized or carbonized to form a leak gap.
At this point, a new packing can be replaced to restore its sealing performance. The cost of packing is very low, which is not as good as other high pressure seals. However, the packing and weight of the packing seal is very large, far less compact and lighter than the graphite seal and the ring.
Better known What is the dredge pump packing seal, contact dredge pump for sale - China Do Pump at info@dopumogroup.com or call us at +8615031104888.
