Novel double end face mechanical seal
Technical field
The utility model relates to centrifugal type slurry pump field, particularly a kind of Novel double end face mechanical seal for centrifugal type slag-slurry Pump Shaft Seal.
Background technique
Pulp pump is used to carry the flowing medium containing solid particle, and namely a kind of equipment of slag slurry, is widely used in multiple industries such as chemical industry, coal, metallurgy, electric power, mining production, and may be used for blowdown irrigation, and purposes is very extensive.Pulp pump adopts centrifugal structure usually.
Pulp pump comprises bracket, pump shaft, impeller, the rear pump housing, volute and decompression lid etc.The rear pump housing is connected on bracket, and decompression lid is connected with the rear pump housing, and decompression lid side is provided with mechanical seal.Mechanical seal is named end face seal again, is to be kept fitting under hydrodynamic pressure and the effect of compensation mechanism pressure (or magnetic force) and the cooperation of auxiliary seal by least one pair of end face perpendicular to spin axis and relative sliding and the device preventing flowing medium from revealing that forms.
Pulp pump is in the process of running, and the continuous running of protection to Pulp pump of shaft seal and bearing seal plays vital effect.Usual employing rotating ring is at interior, stationary ring double-face mechanical sealing structure outside, and the sealing of interior rotating ring and outer stationary ring mainly relies on little spring to provide elastic force that rotating ring and stationary ring are fitted tightly, to improve the reliability of mechanical seal as far as possible.
But, above-mentioned rotating ring is at interior, stationary ring double mechanical seal outside, mechanical seal opening is easily caused when there is moment impulse force when starting shooting or in operation process, namely gap is had between rotating ring and stationary ring, the easy like this flowing medium that makes enters in mechanical seal dynamic and static ring working surface and Seal cage, and then causes mechanical seal to be lost efficacy.And little spring is also easy to lose efficacy due to plunger phenomenon, added the probability that opening appears in mechanical seal.
In order to improve the reliability of mechanical seal further, usually little spring can be changed into ripple spring, to overcome the plunger phenomenon that little spring easily occurs, little spring is avoided to lose efficacy because of plunger, thus increase the reliability of mechanical seal, but when there is moment impulse force, mechanical seal still has opening phenomenon to be existed, in the course of time, mechanical seal will slowly be lost efficacy.
In addition, usually adopt water tank to cool mechanical seal for bore at the Pulp pump of below 200mm, main rely on cooling liquid cold and hot convection current and mechanical seal in the rotation of rotating ring, in driving mechanical seal chamber, liquid in rotation accelerates the flowing of cooling liquid.But bore was even lost efficacy the Large Slag stock pump cooling effect of more than 200mm is not good.
Summary of the invention
In view of this, the utility model provides a kind of Novel double end face mechanical seal that reliability is higher in operation process, which reduce the possibility of rotating ring and stationary ring opening, and the cooling effect of water tank can be increased, the Pulp pump for any type is made all to have good cooling effect, guarantee the reliability of the mechanical seal of Pulp pump, reach the effect that machine envelope dropping liquid does not leak.
The utility model provides a kind of Novel double-end-face mechanical seal structure (see Fig. 1) 1, it is characterized in that comprising: annular inner end plate 4, annular outer end plate 6 and the circular cylinder 5 between described inner end plate 4 and described outer end plate 6, described cylindrical shell 5 and described inner end plate 4 and described outer end plate 6 form seal chamber jointly, there are in described seal chamber two stationary rings 9 be separately fixed on described inner end plate 4 and described outer end plate 6 and two rotating rings 7 be close to two stationary rings 9 respectively, two rotating rings 7 are arranged on rotating seat 12 both sides respectively, described rotating ring 7 is pressed on described stationary ring 9 by ripple spring 8, in the outer circumference of described rotating seat 12, be provided with multiple radial blade 10, each in described multiple radial blade 10 is to the certain angle of the opposite direction deflection of sense of rotation.
Described annular inner end plate 4 is fixed on by screw 3 on the decompression lid 2 that coordinates with mechanical seal structure 1.
Described rotating ring 7 is arranged on described rotating seat 12, is fixed by screw and pump shaft 11.
Described radial blade 10 is generally 3-8.
Described radial blade 10 is evenly distributed on the outside excircle of rotating seat 12.
Described sense of rotation is identical with the sense of rotation of pump shaft 11.
The material of described stationary ring 9 and rotating ring 7 is Tungsten carbite, and its hardness is more than HRC80.
The deflection angle of described radial blade is 22.50 degree.
At radial blade 10 along with rotating ring 7, rotating seat 12 can produce the high pressure distribution in low inner side, outside in time rotating together with pump shaft 11 in seal chamber.
Described outside is near described outer end plate 6 side, and described inner side is near described inner end plate 4 side.
Novel double-end-face mechanical seal structure of the present utility model forms the high pressure distribution in low inner side, outside in seal chamber, decrease the possibility of rotating ring and stationary ring opening, and add the cooling effect of Pulp pump water tank, the Pulp pump for any type is made all to have good cooling effect, guarantee the reliability that Pulp pump machine seals, reach the effect that machine envelope dropping liquid does not leak.
Accompanying drawing explanation
Fig. 1 is the overall structure figure according to Novel double end face mechanical seal of the present utility model.
Fig. 2 is the sectional view of rotating seat and radial blade disposed thereon.
Fig. 3 is the schematic diagram of the opposite direction deflection of radial blade and sense of rotation.
Embodiment
For making the purpose of this utility model, technological scheme and advantage clearly understand, to develop simultaneously embodiment referring to accompanying drawing, the utility model is further described.
Fig. 1 is the overall structure figure according to Novel double end face mechanical seal of the present utility model.This mechanical seal structure 1 comprises annular inner end plate 4, annular outer end plate 6 and the circular cylinder between inner end plate 4 and outer end plate 65, annular inner end plate 4 is fixed on the decompression lid 2 that coordinates with mechanical seal structure 1 by screw 3, cylindrical shell 5 and inner end plate 4 and outer end plate 6 form seal chamber jointly, have in seal chamber and be separately fixed in circular cylinder, outer end plate 4, two stationary rings 9 on 6, two rotating rings 7 be close to two stationary rings 9 respectively, two rotating rings 7 are arranged on rotating seat 12 (shown in Figure 2) both sides respectively, fixed by screw and pump shaft 11, rotating ring 7 is pressed on stationary ring 9 by ripple spring 8, produce contact, medium not by, reach seal action.The material of stationary ring 9 and rotating ring 7 is Tungsten carbite, and its hardness is more than HRC80.
Cooling liquid is connected with, such as cooling water, when Pulp pump works in seal chamber, pump shaft 11 High Rotation Speed, can drive rotating seat 12, rotating ring 7 together rotates, the heat that rotating ring 7, stationary ring 9 High Rotation Speed produce is cooled by cooling water, Pulp pump is obtained and normally works.
Fig. 2 is the sectional view of rotating seat and radial blade disposed thereon.As shown in Figure 2, the outer circumference of rotating seat 12 is also provided with multiple radial blade 10, the quantity of radial blade does not limit, and be generally 3-8, they are evenly distributed on the excircle of rotating seat 12.Assuming that sense of rotation is the sense of rotation of pump shaft, then each radial blade 10 is to the certain angle Φ of the opposite direction deflection of sense of rotation, angle Φ is such as 22.50 degree, thus (the side away from decompression lid 2 of seal chamber, outside can be produced when radial blade 10 plays rotation along with rotating seat 12-, namely near outer end plate 6 side) low, the pressure distribution that inner side (side near decompression lid 2 of seal chamber, namely near inner end plate 4 side) is high.The shape of radial blade 10 can be a flat board, and for diameter of axle 100mm machine envelope, preferably, the size of radial blade 10 can be chosen as long 10mm, wide (thickness) 5mm, high 10mm.The corner angle of blade need abate.Blade material is identical with rotating seat, is generally 3Cr13.As shown in Figure 2, can gap be had between the inwall of blade 10 external diameter and annular tube wall 5, be preferably 2mm.
Fig. 3 is the schematic diagram of the opposite direction deflection of radial blade and sense of rotation.Each radial blade 10 is to the certain angle Φ of the opposite direction deflection of sense of rotation, and angle Φ is such as 22.50 degree.
Like this, under the effect of radial blade 10, when rotating seat 12 is along with pump shaft 11 High Rotation Speed, cooling liquid in meeting driving mechanical seal chamber together rotates, such radial blade 10 forms an axial-flow pump with circular cylinder 5, produce the power of an axis, the rotating ring of close slurry one end that the power of this axis makes and the tighter of stationary ring pressure, cooling water pressure increases, and in the pump that contends with, slurry pressure prevents sealed open, and outside cooling water pressure step-down, balance each other with atmospheric pressure, in case cooling water spills, and can accomplish that dropping liquid does not leak, and improves operating environment.
The foregoing is only preferred embodiment of the present utility model, be not intended to limit protection domain of the present utility model.All within spirit of the present utility model and principle, any amendment done, equivalent replacement and improvement etc., all should be included within protection domain of the present utility model.