| Home>Bearing knowledge>Features of high viscosity gear pump |
Development characteristics of high viscosity gear pump
Source: Bearing network time: 2017-10-16
| /*250*250 was created on 2017/12/25*/ var cpro_id = 'u3171089'; |
At present; although domestic enterprises have produced a lot of gear pumps suitable for transporting high-viscosity liquids; but because the test methods are not perfect; there are still some problems in data selection, leakage and noise prevention. Especially the domestic high-viscosity gear pumps Power, reliability and service life have a great distance from foreign products. Therefore, most of the high-viscosity gear pumps used in China's petroleum and chemical industries still rely on imports. The current life is used; the characteristics of high-viscosity gear pumps at home and abroad as follows:
Gear layout High-viscosity gear pump gears commonly have straight teeth, helical teeth, herringbone teeth, spiral teeth; tooth profiles are mainly involute and arc type. Generally small gear pumps use involute spur gears; high temperature gears Pumps often use displacement gears; melt pumps that transport high-viscosity, high-pressure polymer melts use involute helical gears. Gears are integrated with the shaft; their rigidity and reliability are higher than those of gears and shafts. The gears of foreign low-pressure gear pumps often use a square layout; that is, the tooth width of the gear is equal to the diameter of the tip circle. The gear width of the high-viscosity gear pump used in high-pressure applications is smaller than the diameter of the tip circle; this is to reduce the gear Radial compression area; drop gear, bearing load.
The pump body and heating method are generally; the heavier the pump casing of the gear pump; the higher the temperature resistance and the compressive strength. The pump body data often uses ductile iron; it can also be cast by casting aluminum alloy hard mold; or Kneading aluminum alloy profile processing. When the medium to be transported is corrosive; optional stainless steel materials can be used. Foreign high viscosity gear pumps use alloy steel with high nickel and chromium content as the pump casing data; The induction function in terms of strength, reliability and cost is better. It is used to deal with the oily appearance of the gear pump; generally, a symmetric relief groove is opened on the pump cover; or an asymmetric relief groove is opened in the direction of the low pressure side; The taper unloading groove is selected; the drain side is a rectangular unloading groove; the depth of the unloading groove is also deeper than that of the gear pump used in the hydraulic industry.
Because the viscosity of the medium transported by the high-viscosity gear pump is high; to reduce the active resistance; improve the liquid absorption of the pump; it is necessary to heat or heat the medium. Generally, the heating element is used for heating; the viscous liquid can be heated evenly. If the temperature is shaken It is not big; when the high-viscosity liquid is easily degraded; it is recommended to use the fluid heating method; especially the gear pump with large displacement. The fluid heating is divided into the built-in and external layout. The so-called built-in type refers to the pump body or end of the gear pump. The inside of the cover is characterized by a heat jacket; the external type is connected to the pump body by bolts. The steam and heat transfer oil are introduced into the jacket; the cooling water is still provided; it depends on the specific conditions of the medium. Built-in It is suitable for the occasional demand for uniformity of transport liquid temperature; or where it is required to uniformly cool high temperature liquid. When the electric heating method lacks safety or the temperature control demand is not high; optional external layout. VIKING company of the United States produces Internal gear pump; some of the pump heads are capable of handling the temperature of the transport fluid; whether in high or low temperature environments; Jacket.
Bearings, layout and bearings of smooth high-viscosity gear pumps generally use sliding bearings; and the spiral flow path is specially drawn on the non-bearing surface of the inner wall of the bearing; the direction of the spiral groove is the same as that of the gear shaft. The outer end of the bearing and the pump The inlet port of the bearing is connected; the spiral groove at the inner end of the bearing communicates with the root of the tooth (vacuum portion). When the shaft rotates; the screw effect and the pressure difference between the two ends of the bearing; the cryogenic liquid outside the bearing is sucked into the bearing; the bearing is smoothed and After cooling; flowing into the teeth just after the disengagement; forming a smooth self-suction low-pressure smoothing system with smooth and fast heat dissipation. The strength of the smoothing method is that the smooth liquid entering the bearing is all low-temperature medium; the viscous smooth liquid is easy to form Strong dynamic oil film for carrying. Many smooth liquid circulation continuously removes the heat of the bearing; it has excellent smoothing and cooling effect on the bearing. Because there is enough liquid to fill the root of the gear that has just been disengaged; the gear is greatly improved. Self-priming function of the pump; avoiding the phenomenon of suction; not only improving the volumetric power; it is also beneficial to reduce cavitation and reduce noise. Sichuan Discussion hospital mechanical drawing plain bearing soaked in selection medium; forced through a special channel is smooth; this skill has been successfully used in the scope of the gear pump vinylon, polyester, rubber, resins, fertilizers and the like.
Recommend to friends comments close window
| Bearing related knowledge |
| Removal, overhaul and discriminating motor bearing wear of KOYO bearings Skf imported bearing shelling failure reason analysis of oil film NSK bearing oil smooth handling rolling bearing convention view preparation work |
This article links to http://
Please indicate China Bearing Network http://
Previous: Bearing steel for unique environment: The reason and avoidance of grinding cracks in carburized and quenched parts
Thermostatic faucets also called thermostatic taps or thermostatic valves. It`s having or maintaining a consistent temperature. You will not feel too cold or too hot when open the faucet (also spigot or tap: see usage variations) for washing and drying.
Thermostatic Faucet,Exposed Thermostatic Shower Faucet,Thermostatic Shower Set,Bathroom Thermostat Faucet
Kaiping Jenor Sanitary Ware Co., Ltd , https://www.jmjenorsanitary.com