CN202326374U

CN202326374U - Dual-end surface mechanical seal

Info

Publication number: CN202326374U
Application number: CN2011202826200U
Authority: CN
Inventors: 韩乐工
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-08-05
Filing date: 2011-08-05
Publication date: 2012-07-11
Anticipated expiration: 2021-08-05

Abstract

The utility model provides a dual-end surface mechanical seal which consists of a positioning packing structure, a dual-end surface sealing structure and a positioning locking structure, wherein the positioning packing structure is formed by embedding a positioning packing in a ring-shaped rectangular groove comprising a cover board, an inner ring of a static ring and an excircle surface of the front end of a shaft sleeve under the matching of a static ring screwing bolt, a positioning pin and a static sealing ring; the dual-end surface sealing structure is formed by serially connecting and sleeving the static ring, a movable ring and a compensating ring on the shaft sleeve, arranging the static ring, the movable ring and the compensating ring in a closed cavity formed by connecting a sealing sleeve and a gland by using threads, and connecting the movable ring with the shaft sleeve by adopting a shifting fork and arranging floating packings in an external diameter groove and the internal diameter of a sealing sleeve under the matching of the sealing ring; and the positioning locking structure is formed by clinging a spring seat extending into a gland back hole to form shifting fork connection with the tail part of the compensating ring and being provided with a small spring to a locking positioning cover, and the locking structure comprises a locking bolt and a locking nut. The dual-end surface mechanical seal has a good sealing effect and wide application range, and can realize safe and reliable long-service-life operation without using sealing oil or by using little sealing oil.

Description

A kind of double mechanical seal

Technical field

The present invention relates to the mechanical seal that running shaft is used, is a kind of double mechanical seal specifically.

Background technique

In commercial production, particularly in petrochemical industry is produced, in order to guarantee the not contaminated destruction of production safety and ecotope; Carry the rotating machinery of various flowing mediums for those, the use of various mechanical seals often becomes first-selection, because these known mechanical seal good sealing effects; Can accomplish zero leakage, but carry those unclean and be that high temperature is inflammable and explosive, poisonous and hazardous flowing medium; Or operating mode is abominable, i.e. intermitten service is prone to find time; Be prone to want on the rotating machinery of vibration make known these mechanical seal structures that just make good use of must the increase sealing oil system; Just might make these known mechanical seals realize using effect preferably, the result who does has so not only increased the cost of mechanical seal operation and maintenance, and not from eliminating the easy potential safety hazard of opening of known these mechanical seal end surfaces now in essence; Particularly on high temperature oil pump; Too much also can cause such security incident of catching fire if cross ambassador's oil sealing because of face opening to the external environment condition leakage, and oil sealing is too much also not all right to the device interior leakage, this not only can influence the quality of product; Even can cause that also equipment finds time to make production technology generation influence of fluctuations steadily to produce, operation accident takes place.

Summary of the invention

The present invention provides a kind of good sealing effect, can use no or little a kind of double mechanical seal that oil sealing also can move the safe and reliable long lifetime.

Said double mechanical seal, by the positioning disk root architecture, double seals structure and positioning and locking structure three parts are formed:

Stationary ring is tightened screw is locked at cover plate and stationary ring stuffing box gland under the cooperation of locating stud and stationary ring seal ring bottom; The ring-type rectangle groove that constitutes ring-type convex slot and the annular concave groove composition of axle sleeve front end periphery at the inner ring of cover plate and stationary ring has been embedded in the location packing and has constituted the positioning disk root architecture, has fixed the axial seat of axle sleeve in mechanical seal;

Be enclosed within by stationary ring, rotating ring and compensated loop polyphone and be contained on the axle sleeve in the enclosed cavity that stuffing box gland and gland form with scyewed joint; Rotating ring and axle sleeve adopt shift fork to be connected, are furnished with the unsteady packing of rotating ring and under the cooperation of seal ring of moving ring assembly and compensated loop seal ring, have constituted the double seals structure with the stuffing box gland internal diameter in its external diameter groove;

Form with the compensated loop afterbody by stretching in the gland dorsal pore that shift fork is connected and spring seat and locking and positioning lid that little spring is housed is adjacent to and constituted the positioning and locking structure by the lock bolt and the locking nut that are tightened on the gland.

Rotating ring rotates together with axle sleeve under the effect of shift fork and can axially slide the back in front along sleeve outer circle simultaneously; Thereby can remain in position when string is moving before and after axle sleeve takes place; Realized the axial float of rotating ring, former and later two end clearances that rotating ring and stationary ring and compensated loop are formed remain in working order.

After the locking and positioning lid is locked; The spring seat that little spring is housed can only promote compensated loop forward and with compensated loop end face and rotating ring ear end face under the effect of spring force; Two couple that rotating ring front-end face and stationary ring end face are formed sassafras pair of rubbing is adjacent to and forms the micron-sized working clearance, because friction pair all is to form with wear-resisting hard material, thereby its end clearance only can be because of slowly increase of wearing and tearing in working long hours; But because the effect of spring force can be compensated immediately; Even thereby the end clearance of this mechanical seal when pump depletion causes rotating shaft generation high vibration can not be opened suddenly to become big, be that spring seat and locking and positioning cover faying surface and can be easy to detect end face working clearance state simultaneously at E place, when this gap becomes big; Explain that the friction pair wearing and tearing are bigger; Can reorientate the locking and positioning lid through lock bolt and locking nut again this moment, made zero in its gap, thereby realized the online repair function of mechanical seal.

Structure characteristic by above further specifies: when axle sleeve is fixed in the rotating shaft when rotating together with axle by positioning screwn; The medium that is sealed can only lead to individual by the gap between location packing and the axle sleeve successively; The end clearance that forward and backward two pairs of fastnesses that stationary ring, rotating ring, rotating ring floating disc interradicular space and compensated loop constitute form leaks in the cooling chamber that under spring seat seal ring and spring seat and locking and positioning lid cooperate, is made up of circle in the compensated loop and axle sleeve external diameter cylndrical surface; And by after the water quench that gets into from the gland cooling water inlet from the gland coolant outlet wash away; Because the gap between location packing and the axle sleeve is very little thereby can effectively the hard impurity in the medium be filtered out; Thereby the medium that gets into end face is kept clean; And the end clearance can remain at micron-sized working state and makes passing through that medium only maybe minute quantity under the effect of positioning and locking structure; Thereby this double mechanical seal good sealing effect not only, be easy to realize zero leakage, and can not produce the end clearance and open change rapidly and be directed at the medium potential safety hazard that the end face promptly said usually opens that leaks in a large number greatly; Therefore have the very strong anti-anti-vibration performance of finding time, just can guarantee the safe and reliable work of mechanical seal long lifetime so can save oil sealing.

Advantage of the present invention is: compact structure; Thoroughly eliminated easy unlatching of end face that known mechanical seal exists; The weak potential safety hazard of anti-pumpage, not only safe and reliable life-span length but also mechanical seal operation and maintenance cost decline to a great extent, thereby have use value widely.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is the axial front elevational schematic of seeing from Fig. 1 right-hand member;

Fig. 3 is the structural representation that the present invention is applicable to cantilever pump;

Fig. 4 is that the present invention is applicable to the structural representation that the Seal cage axial dimension is short.

Among the figure; The 1-axle sleeve, the 2-stationary ring is tightened screw, the 3-cover plate, the 4-locating stud, 5-locatees packing, 6-stationary ring seal ring; 7-stationary ring, the 8-rotating ring packing that floats, 9-seal ring of moving ring assembly, 10-rotating ring, 11-stuffing box gland, 12-compensated loop; 13-compensated loop seal ring, 14-gland ring, 15-gland, 16-spring seat seal ring, 17-gland bolt; The 18-spring seat, 19-little spring, 20-locking and positioning lid, 21-dust ring, 22-axle sleeve Cock screw; The 23-lock bolt, 24-locking nut, 25-sleeve sealing coil assembly, 26-axle sleeve forward end seal circle, 27-sleeve sealing pad; Cover at the bottom of the 28-, A, A '-shutoff medium gateway, B, (C), B ' (C ')-cooling water inlet/outlet, E-end clearance monitoring circle.

Embodiment

Below in conjunction with accompanying drawing the present invention is further described.

The structural representation that is entire equipment at assembling double mechanical seal of the present invention as shown in Figure 1:

Gland 15 be with gland bolt 17 be fixed on the static apparatus body and gland ring 16 compressed prevent that the medium that is sealed from leaking from here.

Axle sleeve 1 is to be fixed in the rotating shaft of equipment with axle sleeve holding screw 22 to rotate with axle, and sleeve sealing coil assembly 25 and axle sleeve forward end seal circle 26 can prevent effectively that sealed medium from leaking from the radial clearance of axle sleeve and axle.

Stuffing box gland 11 is close-connected with screw thread with gland 15.

In the annulus that is contained in the sealing that constitutes by sealing shroud 11, gland 15, spring base 18 and axle sleeve 1 that stationary ring 7, rotating ring 10 and compensated loop 12 are just connected, tighten that screw 2 is locked at cover plate 3 and stationary ring 7 bottom of sealing shroud 11 under the help of alignment pin 4 and stationary ring sealing ring 6 compressed by stationary ring and guarantee that sealed medium can not leak from here and will locate the position that packing 5 is locked in each part that makes axle sleeve 1 and mechanical seal in the ring-type rectangular channel that is made of cover plate 3, stationary ring 7 and axle sleeve 1 front end simultaneously and all obtain being relatively fixed.

Therefore whole invention structure has following characteristic: just represent that when compressing locking and positioning lid 20 little springs 19 with spring seat 18 when making end clearance monitoring circle E be in zero state (in fact this E is exactly spring seat 18 and the faying surface of locking and positioning lid 20) little spring is in normal working state; Former and later two end faces that this moment, rotating ring 10, stationary ring 7 and compensated loop 12 were constituted also have been adjacent to; But this to be adjacent to be with good conditionsi; Those two end faces when assembling are the lubricant oil that will coat cleaning; Seem that two end faces are to be adjacent to, in fact between two end faces one deck oil film is arranged, and this oil slick thickness gap of end face work just; Bolt 23 overtorquings so locking and positioning lid 20 can not be locked; Its tight power will be controlled by locking nut 24, just when twisting lock bolt 23, wants jiggering to guarantee with locking nut 24 lock bolt 23 to be fixed after the rotation normally, thereby realizes the purpose of sealing locking and positioning.

From the above process, we can see that it is unnecessary to consider thermal expansion headroom left and shaft sealing work on strings impact, because the sealing sleeve 11 and the stationary ring 7, the snap ring 10 and ring 12 are used compensating thermal expansion Ito made of a material the same number, and 7 embedded in the stationary ring, snap ring 10 and the compensation ring 12 on the friction coefficient of thermal expansion are small with a high hardness made of wear-resistant material, the sealing sleeve 11 when heated and static ring 7, snap ring 10 and compensation of thermal expansion ring 12 is just the same as the direction of elongation and complementary, and a snap ring 10 and the sleeve is connected with a fork but you can only rotate with the shaft in the axial direction of the hub ago , after the slide ring seal assembly 9 to prevent the media from the driven ring 10 and the sleeve 1 is formed in an annular radial gap leakage effect, so taking the time axis of the device prone to vibration or the axial direction moving string ring 10 does not affect the axial position that is not affected by the strong two end clearance change, is the case, the present invention is a double mechanical seal in the installation are not as well known as a mechanical seal to stay under mounting clearance (and this gap is usually in about 2 mm) leaving the direct control of this gap is set at 2 micron film state, thus completely eliminating the mechanical seal faces easy to open a big security risk, coupled with the positioning packing the role of the media in filtering large hard particles is difficult to enter end clearance, so in the absence of seal oil under the condition of the present invention can also double mechanical seal safe and reliable long-life work.

When end wear might increase the gap; Can observe from seal clearance monitoring circle E fully; Because under the effect of spring force; The gap can appear in the E place, only needs this moment of short duration shutdown that location locking mechanism is readjusted and makes E place belong to zero sealing to be under the first dress state worked on, so mechanical seal of the present invention also has good online repair ability.

Because two end faces are operated in series connection, medium can only get into ear end face from front-end face successively, and the end clearance all remains under the very little state all the time and also has very strong complementarity; Be front-end face gap when becoming big, the ear end face gap must diminish, because two end face axial distances of stationary ring 7 and compensated loop 12 are definite values under the effect of location locking mechanism; The axial dimension of rotating ring also is a definite value and just is embedded in middle; Obviously these two end clearances can not increase simultaneously, thereby the dielectric leakage amount can not increases suddenly and can remain at that critical field is interior to be taken away by cooling water, if to be poisonous and harmful inflammable and explosive when allowing anything but to leak in the atmosphere environment for the medium that is transferred; Just can be with the A introducing of shutoff medium from the shutoff medium inlet; This moment, the shutoff pressure medium need only be just more passable than the big 0.05～0.1MPa of pressure medium that is sealed, because it is very little and can not open very greatly to be in the front-end face gap that is sealed, adds that again the shutoff pressure medium is only than the big 0.05～0.1MPa of pressure medium that is sealed; So add the throttling action shutoff medium of the unsteady packing 8 of rotating ring is to be difficult in a large amount of access arrangements; Have only a spot of shutoff dielectric leakage raffinate water that can be cooled to take away, so the shutoff medium consumption of this double mechanical seal of the present invention also is very little, as long as the medium that is sealed with water repulsion and chemical change does not take place; The complete available cooling water of shutoff medium and be fully feasible without oil sealing; Connect water-cooling tube and load onto the control valve control water yield and pressure at shutoff media outlet A ' this moment, just can make cooling water play good shutoff and cooling action, can not only realize the zero leakage of medium; Can also conserve water; When equipment carries deep cooling to be prone to the medium of vaporization, but need only introduce just proper functioning of an amount of steam, if adopt dry gas seals from shutoff medium inlet A; Then only need in the shutoff medium inlet A to introduce and intercept gas, B or C introduce nitrogen and draw feeding torch pipe network by B ' or C ' outlet and just can realize dry gas seals in the cooling water inlet.

And introduce cooling water by B (C) at general next need of operating mode, just draw by B ' (C ') and can guarantee safety and cleaner production.

Fig. 3 is the of the present invention a kind of structural representation that is fit to be installed on the cantilever pump, and different with Fig. 1 is: stationary ring 7 unites two into one with stuffing box gland 11, promptly directly is embedded in the stuffing box gland bottom to wear ring; The stuffing box gland (7,11) that constitutes the band stationary ring has saved stationary ring seal ring 6; Location packing 5, locating stud 4, cover plate 3 is tightened screw 2 with stationary ring; 1 on axle sleeve the same with known cantilever pump sealing axle sleeve by axle with nut check on axle; Just end mill grooving shape is connected with rotating ring 10 formation shift forks behind axle sleeve this moment, and rotating ring can be rotated with the axis, and can forward and backwardly vertically move again; Under the cooperation of gland, in stationary ring stuffing box gland (7,11), constitute double mechanical seal with compensated loop 12.

Fig. 4 then is that the present invention is applicable to the structural representation that the Seal cage axial dimension is short; Different with Fig. 3 is: axle sleeve or being tightened in axle with axle sleeve Cock screw 22 goes up and axle rotation together; Dust ring 21 is made up of the abrasion-resistant metal ring that can be split into two halves; Be contained in the groove of axle sleeve and be fixed in the locking and positioning lid in the circular hole, prevent it and deviate from thereby fix the axial position of axle sleeve in double mechanical seal.

The above; Be merely embodiment of the present invention, but protection scope of the present invention is not limited thereto, any technician who belongs to the present technique field is in the technical scope that the present invention discloses; The variation that can expect easily or replacement all should be encompassed within the protection domain of the utility model.Therefore, protection scope of the present invention should be as the criterion with the protection domain of claim.

So; The present invention compares with existing known double mechanical seal and has only structurally carried out simple improvement; Manufacture cost and technology do not have big variation just to make the operational safety of double mechanical seal, and Security has obtained significant raising and assurance, and have strengthened the online repair ability of double mechanical seal; Reduced operation expense and can use different shutoff media to use no or little oil sealing according to different sealed mediums; As long as part and friction pair material are selected well, face pressure is reasonable, and double mechanical seal of the present invention just has the using effect of using prospect and excellence widely.

Claims

1. double mechanical seal is characterized in that: by the positioning disk root architecture, double seals structure and positioning and locking structure three parts are formed:

Stationary ring is tightened screw (2) is locked at cover plate (3) and stationary ring (7) stuffing box gland (11) under the cooperation of locating stud (4) and stationary ring seal ring (6) bottom; The ring-type rectangle groove that constitutes ring-type convex slot and the annular concave groove composition of axle sleeve (1) front end periphery at the inner ring of cover plate and stationary ring has been embedded in corresponding location packing (5) and has constituted the positioning disk root architecture, has fixed the axial seat of axle sleeve in double mechanical seal;

Be enclosed within by stationary ring (7), rotating ring (10) and compensated loop (12) polyphone and be contained on the axle sleeve (1) in the enclosed cavity that stuffing box gland (11) and gland (15) form with scyewed joint; Rotating ring (10) and axle sleeve (1) adopt shift fork to be connected, in its external diameter groove and stuffing box gland (11) internal diameter be furnished with the unsteady packing (8) of rotating ring and under the cooperation of seal ring of moving ring assembly (9) and compensated loop seal ring (13), constituted the double seals structure;

Form spring seat (18) that shift fork is connected and is equipped with little spring (19) and locking and positioning lid (20) with compensated loop (12) afterbody and be adjacent to that to make gap, E place be zero and lock and constituted the positioning and locking structure by stretching in gland (15) dorsal pore by being tightened in lock bolt (23) and locking nut (24) on the gland (15).

2. according to the said double mechanical seal of claim 1; It is characterized in that: rotating ring (10) is under the effect of shift fork and axle sleeve (1) rotates together and the while can axially slide before and after axle sleeve (1) periphery; Thereby can remain in position when string is moving before and after axle sleeve (1) takes place; Realized the axial float of rotating ring (10), rotating ring (10) and former and later two end clearances that stationary ring (7) and compensated loop (12) form are remained in working order.

3. according to the said double mechanical seal of claim 1; It is characterized in that: after locking and positioning lid (20) is locked; The spring seat (18) that little spring (19) are housed can only promote compensated loop (12) forward and with compensated loop (12) end face and rotating ring (10) ear end face under the effect of spring force; Two couple that rotating ring (10) front-end face and stationary ring (7) end face are formed sassafras pair of rubbing is adjacent to and forms the micron-sized working clearance, because friction pair all is to form with wear-resisting hard material, thereby its end clearance only can be because of slowly increase of wearing and tearing in working long hours; But because the effect of spring force can be compensated immediately; Even thereby the end clearance of this mechanical seal when pump depletion causes rotating shaft generation high vibration can not be opened suddenly to become big, be that spring seat (18) covers (20) faying surface with locking and positioning and can be easy to detect end face working clearance state simultaneously at E place, when this gap becomes big; Explain that the friction pair wearing and tearing are bigger; Can reorientate locking and positioning lid (20) through lock bolt (23) and locking nut (24) again this moment, made zero in gap, E place, thereby realized the online repair function of mechanical seal.

4. according to the said double mechanical seal of claim 1, it is characterized in that: stationary ring (7) and stuffing box gland (11) unite two into one, and promptly directly are embedded in stuffing box gland (11) bottom to wear ring; The stuffing box gland (11) that constitutes band stationary ring (7) has saved stationary ring seal ring (6); Location packing (5), locating stud (4), cover plate (3) and stationary ring are tightened screw (2); Axle sleeve (1) then the same with known cantilever pump sealing axle sleeve by axle with nut check on axle; Just end mill grooving shape is connected with rotating ring (10) formation shift fork behind axle sleeve this moment, and rotating ring can be rotated with the axis, and can move forward and backward vertically again; Under the cooperation of gland, in stationary ring stuffing box gland (7,11) and compensated loop (12) constitute double mechanical seal.

5. according to claim 1 or 4 said double mechanical seals; It is characterized in that: axle sleeve (1) still is tightened in axle with axle sleeve Cock screw (22) and goes up and axle rotation together; Dust ring (21) is made up of the abrasion-resistant metal ring that can be split into two halves; Be contained in the groove of axle sleeve (1) and be fixed in locking and positioning lid (20) interior circular hole, prevent it and deviate from thereby fix the axial position of axle sleeve (1) in double mechanical seal.