DE102013203266A1 - Method for mounting a sealing element on a shaft part and sealing element - Google Patents

Abstract

The invention relates to a method for assembling a sealing element (1) on a shaft part (2), the sealing element (1) rotating around the shaft part (2) in a circular manner in the assembled state. In order to simplify the assembly process, the invention provides the following steps: a) Providing the sealing element (1) as a longitudinally extending element with two butt ends (3, 4), with a tensioning tab (5 , 6) is attached to the sealing element (1); b) wrapping around the shaft part (2) with the sealing element (1) so that the two butt ends (3, 4) are opposite one another; c) Attaching a pulling tool (7) which is designed to engage positively in the two clamping straps (5, 6) and pulling the two joint ends (3, 4) together in the circumferential direction (U) of the shaft part (2) until the joint ends meet (3, 4) contact; d) connecting the two butt ends (3, 4); e) Disassembly of the pulling tool (7). The invention also relates to a sealing element (1) for mounting on a shaft part.

Description

The invention relates to a method for mounting a sealing element on a shaft part, wherein the sealing element circulates in the assembled state circularly around the shaft part. Furthermore, the invention relates to a sealing element for mounting on a shaft part.

In larger machine arrangements, such as in the field of wind turbines or in the field of mine machines, seals are required on large diameter shaft elements. These seals are often designed as V-ring seals. The seals can be pressed and cut as exchange goods; they can also be manufactured as extruded cross sections. If a seal has to be mounted or replaced, it is then placed on or in the machine around the shaft and the two joints are fixed against each other.

This is done either by pressing the shocks against each other alone; but then a gap in the sealing element remains in the joint area.

Alternatively, the two butt ends may be bonded together by vulcanization. For this purpose, the butt ends must be fixed in a heatable tool during vulcanization against each other. As a result, a joint is produced which has a relatively high tensile strength.

To vulcanize V-rings, a corresponding tool is needed. Due to the size of the tool and the manner of joining, the sealing ring must be pulled or expanded relatively strongly in the radial and in the axial direction. The sealing element can thereby be damaged. The entire process requires a relatively large amount of space and power, which usually disadvantageously requires two people to do the assembly.

Furthermore, it is disadvantageous that the vulcanizing tool becomes hot and thus represents a potential source of danger for the employees.

Due to the relatively high power consumption of the heated Vulkanisationswerkzeugs an electrical power supply is required for this. For repairs, this often means additional logistical effort or even the non-feasibility of the repair, which is another disadvantage of the known assembly process.

Finally, it is disadvantageous that the assembly process is quite time consuming. Depending on the type of rubber, vulcanization takes 15 to 30 minutes and cooling takes about 1 hour.

Due to the required longitudinal expansion of the sealing element during vulcanization usually only sealing profiles come into question, which are fixed on the shaft with a clamping band. This is also disadvantageous.

Also a bonding of the two butt ends is known. However, this is so far problematic for the following reasons: The required elongation of the V-ring is not easy to perform, d. H. the two butt ends can be difficult to each other out to allow bonding. A certain elongation of the ring is required so that the ring sits stably on the shaft, d. H. it can not be mounted in a larger diameter ring. Furthermore, the prior art bond is not stable enough to ensure that the ring remains stable on the shaft for the expected service life. There are cases have become known in which bonded rings by releasing the bond after a short time fall off the shaft again.

The invention has for its object to propose a generic method and a corresponding sealing element with which the mentioned disadvantages can be overcome. Accordingly, it should be possible to mount a sealing element with a slight overstretching on a shaft part, this being easier, namely

to be carried out by a single person. Furthermore, it should be given independence from an electrical power connection.

• a) Bereitstellen des Dichtungselements als sich längserstreckendes Element mit zwei Stoßenden, wobei im Bereich der beiden Stoßenden je mindestens eine Spannlasche am Dichtungselement befestigt ist;
• b) Umschlingen des Wellenteils mit dem Dichtungselement, so dass sich die beiden Stoßenden gegenüberliegen;
• c) Ansetzen eines Zugwerkzeugs, das zum kraftschlüssigen und/oder formschlüssigen An- oder Eingreifen an den und/oder in die beiden Spannlaschen ausgebildet ist, und Zusammenziehen der beiden Stoßenden in Umfangsrichtung des Wellenteils, bis sich die Stoßenden kontaktieren;
• d) Verbinden der beiden Stoßenden;
• e) Demontage des Zugwerkzeugs.

The solution of this object by the invention is characterized in that the method of assembling the sealing element comprises the steps of:

• a) providing the sealing element as a longitudinally extending element with two butt ends, wherein in the region of the two butt ends each at least one clamping tab is attached to the sealing element;
• b) looping around the shaft part with the sealing element, so that the two butt ends face each other;
• c) applying a pulling tool, which is designed for frictional and / or positive engagement or engagement on the and / or in the two clamping straps, and contraction of the two butt ends in the circumferential direction of the shaft part, to contact the butt ends;
• d) connecting the two butt ends;
• e) Dismantling of the pulling tool.

The joining according to step d) can take place in various ways, in particular by material bond and / or by friction or positive connection.

Concretely, the joining of the two butt ends according to step d) can be a material-locking connection, in particular a gluing.

Upon contraction of the two butt ends according to the above step c), the two butt ends are preferably guided laterally to ensure an offset-free merging of the butt ends.

The abovementioned step d) preferably comprises a pressing together of the butt ends by means of the pulling tool when the two butt ends are joined together materially.

Another preferred embodiment of the invention provides that in accordance with the above step d) a clamping element is positively engaged on the two clamping straps frictionally engaged or positively engaging in the two clamping straps that the two butt ends are pulled elastically towards each other by the clamping element. Preferably, portions of the clamping element engage in a form-fitting manner in correspondingly formed sections of the two clamping straps.

However, it can also be provided that, in accordance with the above step d), the two clamping straps are (positively) connected to one another in a form-fitting manner, wherein they are preferably hooked together. A clamping element is not necessary in this case.

In such a particularly preferred embodiment of the invention, the clamping straps on at least a pair of sections, which interlock with each other during the vigorous pressing together of the butt ends. In this way, the butt ends are further fixed under pressure after disassembly of the pulling tool, whereby the cohesive connection of the butt ends is supported and strengthened when absorbing tangential tensile forces in the sealing body. Even with a design as a non-material connection of the butt ends, an improvement of the sealing effect between the butt ends is achieved by this pressure-loaded fixation.

The clamping straps are attached according to a preferred solution to the sealing element by the clamping straps heated are placed on the sealing element, so that by local melting of the material of the sealing element results in a cohesive bond between clamping strap and sealing element. Of course, this solution presupposes a corresponding behavior of the material of the sealing element; It is usually used only for thermoplastic materials.

In the case of rubber material, a stable connection between the clamping tabs and the sealing element may optionally be achieved by a vulcanization process, wherein the metal parts are provided with a phosphating.

Alternatively, a gluing or sticking of the clamping straps on the sealing element is possible. Furthermore, a mechanical fastening is possible, in particular by screwing or riveting. Therefore, a development of the invention provides that the clamping straps are attached to the sealing element by an adhesive process or by a mechanical connection, in particular by a screw or rivet connection.

Furthermore, a fastening by a combination of gluing and mechanical fastening is possible; In this case, gluing with subsequent pressing of portions of the tensioning straps with the sealing element is particularly preferred.

The proposed sealing element for mounting on a shaft part is characterized in that the sealing element is designed as a longitudinally extending element with two butt ends, wherein in the region of the two butt ends each a clamping strap is attached to the sealing element.

The sealing element is preferably a radial cut V-shaped seal. Alternatively, an L-shaped training comes into question.

The butt ends of the sealing element are formed deviating from a planar radial section according to a preferred solution, wherein the two butt ends complement each other in their shape complementary. Specifically, it is provided in this respect that the butt ends in a view from the radial direction have at least one V-shaped shape. This ensures that a larger contact surface is available for the bonding of the butt ends, so that the adhesive bond is more durable.

The two clamping straps are preferably attached cohesively to the butt ends. But it can also be provided that the two clamping straps are positively secured to the butt ends. A combination of cohesive and positive connection is possible.

The clamping straps can be connected to each other by means of a positive connection, in particular by means of a hook-shaped connection be, for which appropriate sections may be provided on the clamping straps.

The clamping straps can also be designed for positive engagement with a clamping element. The clamping straps can be designed such that they interact positively with a fully assembled sealing element directly or indirectly via a clamping element.

The positive connection between clamping straps and clamping element may be formed as a hook-shaped connection.

The sealing element may be made of an extruded, linearly extending profile body. But it is also possible that the sealing element is made as a substantially rotationally symmetrical body having in its manufacture substantially the same shape as in its assembled state.

The sealing element is preferably made of a permanently elastic material, which is in particular soft elastic or hard elastic.

The two clamping straps can thus be designed so that they are suitable for positive engagement with each other; Here is particularly thought of a hook-shaped configuration of a clamping tab, which is hooked into a corresponding mating portion of the other clamping strap.

Accordingly, the invention also encompasses a quick-assembly tool with which, in particular, V-ring seals without a strap can be mounted in a simple manner or mounted on a shaft.

The proposed solution achieves the following advantages:
There is no risk of overstretching of the sealing ring during assembly on the shaft part more.

It is a quick and easy connection of the joints of the sealing element produced.

The installation of the sealing element requires significantly less space and effort. It can be done by a single fitter.

No hot (vulcanization) tool is needed anymore, so the safety at work is increased.

Mains power requirement no longer exists for the assembly process.

It is therefore provided according to the invention, a solution in which the splice is additionally strengthened. This is done by the two clamping straps, which remain on the sealing element and produce a positive connection in the region of the splice.

The proposed method is particularly suitable for wind turbines with a combination of labyrinth seals and general sealing elements, which are usually designed as V-ring seals. Preferably, the method is used from a shaft diameter of 200 mm. Here, the advantage comes especially to bear that when replacing a worn V-ring by an inventive sealing element with the invention only a small disassembly and assembly effort is to be driven.

In the drawing, an embodiment of the invention is shown. Show it:

1 schematically a shaft part - seen in the axial direction - on which a sealing element is to be attached, wherein the sealing element is still strip-shaped in the unassembled situation,

2 a section of the shaft part according to 1 in which now the sealing element is placed in a circular shape around the shaft part, facing two butt ends of the sealing element and a pulling tool is attached to the butt ends of the sealing element,

3 in the illustration 2 the butt ends of the sealing element contracted by the tension element,

4 in the illustration 2 the completely assembled sealing element, wherein the butt ends are held together by a tensioning element,

5 schematically a perspective view of a portion of the sealing element in the region of the joints, wherein a V-shaped configuration of the region of the joints is illustrated, and

6 a perspective view analogous to 2 that is, a cutout of the shaft part, with two butt ends of the sealing element facing each other and the pulling tool is attached to the butt ends of the sealing element, wherein the tension straps have sections that hooked together positively during assembly, and

7 a further embodiment of a mounted sealing element.

In 1 is a wave part 2 seen, in the direction of an axis a considered. To the shaft part 2 around is a sealing element 1 Circular to allow a sealing effect to another (not shown) component. The sealing element 1 initially takes the form of a section of a molded or extruded section, cut for assembly, then around the shaft part 2 placed around and finally at his butt ends 3 and 4 is connected. 1 shows how the sealing element 1 just around the shaft part 2 around which its ends are moved in the direction of the arrow until the butt ends 3 . 4 of the sealing element 1 collide. The sealing element 1 has been cut as a molded or extruded endless profile to a length sufficient to allow the sealing element 1 under longitudinal expansion around the entire circumference U of the shaft part 2 lays around. In this case, the circumference of the shaft is greater than the length of the sealing element 1 , so that in the assembled state, a sufficient elongation or stress in the sealing element 1 is generated, making it stable on the shaft part 2 sitting.

In the area of the joints 3 . 4 the initially band-shaped extending sealing element 1 are tension straps 5 . 6 attached, which are better visible in the following figures. The clamping straps are in the present case with the sealing element 1 connected that heated a section of them and then onto the surface of the sealing element 1 was pressed. The material of the sealing element 1 is then locally melted and the clamping strap is partially in the material of the sealing element 1 penetrated. After cooling and hardening of the material of the sealing element 1 is a cohesive bond between the one end of the clamping strap 5 . 6 and the sealing element 1 in front.

Alternatively, the clamping straps 5 . 6 glued to the sealing element with a suitable adhesive. Furthermore, it is possible, the clamping straps 5 . 6 additionally with pins, clips or screws on the sealing element 1 in order to strengthen the connection between these elements.

Alternatively, the clamping straps in the sealing element 1 glued, this can first a receiving groove in the sealing element 1 be introduced.

In 2 you can see that the sealing element 1 Now almost completely around the shaft part 2 was laid around. Now is a pull tool 7 been set, the pull tool 7 two gripping elements 10 and 11 comprising, by means of an actuator 12 can be moved relative to each other.

The gripping elements 10 . 11 can form fit in end areas of the clamping straps 5 . 6 be hung so that the butt ends 3 . 4 upon actuation of the actuator 12 of the pulling tool 7 can be drawn towards each other, which is indicated by the arrows in 2 is indicated.

The actuator 12 can be configured as desired. Preferably, a spindle system is provided, which is actuated for example by hand or by means of a cordless screwdriver. In the same way, however, a pincer-like element can also be used.

Before the butt ends 3 . 4 so by means of the pulling tool 7 so far as to be contracted, they are provided with an adhesive, with a very fast-setting adhesive being preferred ("super glue", for example "Loctite 424" or "Loctite 480"). When selecting the adhesive, the durability of the bond over the service life must also be considered. In this case, and in particular two-component adhesive can be envisaged.

The butt ends 3 . 4 be after application of the adhesive by means of the pulling tool 7 firmly pressed together, so that there is a firm adhesive bond. This is in 3 illustrated.

Before the pull tool 7 is removed, a clamping element 8th positive fit in accordance with the clamping straps 5 . 6 trained recesses mounted (not shown). The tensioning element 8th makes an elastic holding force that the butt ends 3 . 4 holds together. The stability of the (adhesive) connection between the joints 3 . 4 is increased so. The assembled sealing element 1 with mounted clamping element 8th and dismantled pulling tool 7 is in 4 to see.

In a preferred alternative embodiment, those are the other butt end 3 . 4 of the sealing element 1 facing ends of the clamping straps 5 . 6 designed so that when compressing the butt ends 3 . 4 positively connected with each other (eg hooked into one another). Then the (separate) clamping element 8th omitted.

In 5 It can be seen what measures can be taken to ensure the stability of the adhesive bond between the two butt ends 3 . 4 of the sealing element 1 to increase. Looking at the butt ends 3 . 4 in the radial direction r, it can be seen that a V-shaped, complementary design is provided, ie the left butt end 3 has a V-shaped pointed projection 13 on, in a congruent recess 14 in the right butt 4 intervenes.

Hereby, the area available for the production of the adhesive connection surface is substantially increased and the connection stabilized accordingly.

Furthermore, said embodiment ensures precise centering of the two butt ends relative to one another.

According to the proposed approach, therefore, the radially separated at one point V-ring (sealing element 1 ) with on both sides of the separation point glued on clamping straps 5 . 6 delivered. The clamping straps 5 . 6 be with a clamp element (clamping element 8th ) fixed against each other. As already mentioned, but can also with direct positive connection of the clamping straps 5 . 6 , So without clip element, to be worked.

The V-ring (sealing element 1 ) is at the mounting point to the shaft part 2 placed. The pulling tool 7 will be in corresponding openings of the clamping straps 5 . 6 hooked up and the free ends (butt ends 3 . 4 ) of the V-ring are aligned with each other.

Adhesive is then applied to at least one of the previously clean-sealed (adhesive) release surfaces (butt ends) of the V-ring. Alternatively, it is also possible to provide one or both separating surfaces (joints) of the V-ring factory with a suitable contact adhesive. This considerably simplifies handling during assembly (no handling with liquid adhesive at the installation site is necessary). The entire separating surface incl. The sealing lip is glued so. The joint may in this case be provided with a protective film prior to bonding in order not to impair the subsequent adhesive bond by impurities.

The pulling tool 7 can be operated by means of a cordless screwdriver or by hand, whereby the ends or butt ends of the V-ring are approached to each other. The tension heads of the pulling tool 7 are preferably moved toward each other via a threaded spindle; a preferred alternative embodiment provides for a pulling tool 7 in the form of a pair of pliers.

When the butt ends 3 . 4 of the sealing element 1 spaced approximately 20 mm apart, a joining rail (not illustrated) is formed between the parting surfaces over the free butt ends 3 . 4 the sealing lip of the V-ring set to add the sealing lip as offset as possible. This joint rail may be provided at its contact surfaces to the sealing element with a coating which prevents the adhesion of the adhesive to the rail Such a coating can be done for example by PE or PTFE; Adhesive, such as cyanoacrylate, can not bind to this.

The joining surfaces are made by further tensioning of the pulling tool 7 firmly pressed together.

The parting line of the butt ends 3 . 4 can as explained to increase the joining surface and for better alignment V-shaped or similar.

The clamp element (clamping element 8th ) is clamped with a special pliers and with hooking tabs in a trained receiving geometry of the clamping straps 5 . 6 used. The clamping element and the clamping straps are designed so that the tensioned clamping element can neither slip radially nor axially from the clamping straps. The clamping element is preferably made of spring steel. An advantageous alternative is based on another (spring) elastic material, such as PA, PU or PEEK.

After the setting time of the adhesive, the pulling tool 7 relaxed and from the clamping straps 5 . 6 decreased. The joint rail is also removed from the sealing lip.

Now, if necessary, a removal of adhesive residues from the edge of the joint surface. Should it be necessary, the joint can still be smoothed with fine emery paper.

The bonded joining zone is due to the fixed clamping element 8th always under a certain compressive stress; It has thus at the joint a relieving the adhesive surface similar effect, as in the application of tension bands.

The V-ring can now be positioned for its correct function.

For better sliding of the sealing element 1 on the shaft part 2 During assembly, talcum powder is preferably applied to the inner surface of the sealing element 1 applied.

In 6 an alternative embodiment is shown. It can be seen here that the two butt ends of the sealing element 1 by means of the pulling tool 7 pulled together and glued together. Through a guide plate 15 become the two butt ends 3 . 4 precisely aligned with each other aligned.

The clamping straps 5 . 6 are designed so that they are in the merged state of the butt ends 3 . 4 by the formation of a hook connection 16 hold together form-fitting. On a separate clamping element is therefore omitted here.

Then in this embodiment, the already mentioned above and preferred alternative is outlined, after which the two clamping straps 5 and 6 are designed so that they can form a positive connection directly. As can be seen, is a hook connection 16 present, which allows the two clamping straps 5 . 6 be held together positively in the merged state, without it being a separate clamping element 8th would require.

It can be provided that the hook connection 16 is designed so that when contraction of the butt ends by means of the pulling tool 7 the hook connection 16 automatically engages and the positive connection between the clamping straps 5 and 6 manufactures.

7 shows a further preferred embodiment of a sealing element according to the invention 1 , In this case, the clamping straps 5 . 6 sections 5a . 6a on, which is the pressing together of the column ends 3 . 4 so hooked that they in the circumferential direction a solid, self-retaining connection of the column ends 3 . 4 cause. In addition to a gluing are the clamping straps 5 . 6 with fasteners 17 - For example screws - on the sealing element 1 attached, whereby even in the case of detachment of the adhesive layer between clamping straps 5 . 6 and sealing element 1 a strong connection between them is maintained.

LIST OF REFERENCE NUMBERS

1

 sealing element

2

 shaft part

3

 Thrust

4

 Thrust

5

 instep strap

5a

 Section of the tensioning strap

6

 instep strap

6a

 Section of the tensioning strap

7

 pulling tool

8th

 clamping element

9

 V-shaped shape

10

 gripping element

11

 gripping element

12

actuator

13

 head Start

14

 recess

15

 guide plate

16

 hook connection

17

 connecting element

U

 circumferentially

r

 radial direction

a

 axis

Claims (20)

Method for mounting a sealing element ( 1 ) on a shaft part ( 2 ), wherein the sealing element ( 1 ) in the assembled state circularly about the shaft part ( 2 ), characterized in that it comprises the steps of: a) providing the sealing element ( 1 ) as a longitudinally extending element with two butt ends ( 3 . 4 ), whereby in the area of the two butt ends ( 3 . 4 ) at least one clamping strap ( 5 . 6 ) on the sealing element ( 1 ) is attached; b) looping around the shaft part ( 2 ) with the sealing element ( 1 ), so that the two butt ends ( 3 . 4 ) are opposite; c) Placing a pulling tool ( 7 ), which is used for non-positive and / or positive engagement or engagement on and / or in the two clamping straps ( 5 . 6 ) and contraction of the two butt ends ( 3 . 4 ) in the circumferential direction (U) of the shaft part ( 2 ) until the butt ends ( 3 . 4 ) to contact; d) connecting the two butt ends ( 3 . 4 ); e) disassembly of the pulling tool ( 7 ). Method according to claim 1, characterized in that the joining of the two butt ends ( 3 . 4 ) according to step d) of claim 1, a material connection, in particular a bonding, is. Method according to claim 1 or 2, characterized in that when the two butt ends ( 3 . 4 ) according to step c) of claim 1, the two butt ends ( 3 . 4 ) are guided laterally to a mating free merging of the butt ends ( 3 . 4 ). A method according to claim 2 or 3, characterized in that step d) of claim 1 when cohesively connecting the two butt ends ( 3 . 4 ) pressing the butt ends together ( 3 . 4 ) by means of the pulling tool ( 7 ). Method according to one of claims 1 to 4, characterized in that according to step d) of claim 1, a clamping element ( 8th ) in the two clamping straps ( 5 . 6 ) is used interlockingly intervening that the two butt ends ( 5 . 6 ) by the clamping element ( 8th ) are pulled towards each other. Method according to one of claims 1 to 4, characterized in that according to step d) of claim 1, the two clamping straps ( 5 . 6 ) are positively connected to each other, wherein the two clamping straps ( 5 . 6 ) in particular are hooked together. Method according to one of claims 1 to 6, characterized in that the clamping straps ( 5 . 6 ) on the sealing element ( 1 ) are fixed by the clamping straps ( 5 . 6 ) heated to the sealing element ( 1 ) are placed so that by local melting of the material of the sealing element ( 1 ) a cohesive bond between tensioning strap ( 5 . 6 ) and sealing element ( 1 ). Method according to one of claims 1 to 6, characterized in that the clamping straps ( 5 . 6 ) on the sealing element ( 1 ) by an adhesive process or by a mechanical connection, in particular by a screw or rivet connection, are attached. Sealing element ( 1 ) for mounting on a shaft part ( 2 ), wherein the sealing element ( 1 ) in the assembled state circularly about the shaft part ( 2 ), characterized in that the sealing element ( 1 ) as a longitudinally extending element with two butt ends ( 3 . 4 ) is formed, wherein in the region of the two butt ends ( 3 . 4 ) at least one clamping strap ( 5 . 6 ) on the sealing element ( 1 ) is attached. Sealing element according to claim 9, characterized in that the butt ends ( 3 . 4 ) deviating from a planar radial section are formed, wherein the two butt ends ( 3 . 4 ) complement in their shape complementary. Sealing element according to claim 10, characterized in that the butt ends ( 3 . 4 ) in a view from the radial direction (r) at least one V-shaped formation ( 9 ) exhibit. Sealing element according to one of claims 9 to 11, characterized in that the two clamping straps ( 5 . 6 ) cohesively at the butt ends ( 3 . 4 ) are attached. Sealing element according to one of claims 9 to 11, characterized in that the two clamping straps ( 5 . 6 ) form fit at the butt ends ( 3 . 4 ) are attached. Sealing element according to one of claims 9 to 11, characterized in that the two clamping straps ( 5 . 6 ) cohesively and positively at the butt ends ( 3 . 4 ) are attached. Sealing element according to one of claims 9 to 14, characterized in that the clamping straps ( 5 . 6 ) by means of a positive connection, in particular by means of a hook-shaped connection ( 5a . 6a ) are interconnected. Sealing element according to one of claims 9 to 14, characterized in that the clamping straps ( 5 . 6 ) for positive engagement with a tensioning element ( 8th ) are formed. Sealing element according to claim 16, characterized in that the positive connection between clamping straps ( 5 . 6 ) and tensioning element ( 8th ) is designed as a hook-shaped connection. Sealing element according to one of claims 9 to 17, characterized in that the sealing element ( 1 ) is made of an extruded, linearly extending profile body. Sealing element according to one of claims 9 to 17, characterized in that the sealing element ( 1 ) is made as a substantially rotationally symmetrical body having in its manufacture substantially the same shape as in its assembled state. Sealing element according to one of claims 9 to 19, characterized in that the sealing element ( 1 ) consists of a permanently elastic material, which is in particular soft elastic or hard elastic.

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