DE4444350A1 - Bladder, piston or membrane type pressure storage device mfr. - Google Patents

Abstract

The bladder, piston or membrane storage device consists of upper and lower parts, and a separator, eg. bladder, piston or membrane. There is a gas connection and a fluid connection.Mfr. of the unit involves (a) mounting the separator in the lower part (7), (b) assembling the upper and lower parts (8,7), (c) welding the upper and lower parts to form a pressure-tight storage vessel (9), and (d) fixing the fluid connection (11) to the vessel by welding, pref. friction welding. The mfr. process allows rational mfr. of storage devices with fluid connections tailored to individual customer requirements and avoids damage to the separator, already located in the storage vessel, by the welding process.

Description

The invention relates to a method for producing a Bladder, piston or membrane memory that from a Spei cheroberteil, a lower memory part, a separating element (Bladder or piston or membrane) one gas connection and one There is a fluid connection and a device for carrying it out of the procedure.

Bubble, piston and membrane storage of the type affected here are used in facilities in numerous fields of fluid technology used for a pressure accumulator, for example the compensation of the working pressure in a fluid system or for a reserve of certain emergency energy reserves or for compensation or damping of pressure peaks or for compensation and compensation of pump pulsations require.

Due to the incompressibility of liquids, in hydropneumatic pressure accumulators the compressibility of a Gases for fluid storage. Bubble, piston and membrane memories are based on this principle.

These accumulators are generally fluid and fluid Gas part by means of a bubble or a piston or a mem brane divided as a partition.

The fluid part is in contact with the hydraulic fluid circuit Connection so that when the pressure in the fluid circuit rises the pressure accumulator is filled and the gas is compressed. At the Falling pressure expands the compressed gas and presses the stored fluid in the fluid circuit.

The pressure accumulator itself consists of two half-shells, the screwed or welded together or sealed off sealingly nested and otherwise ver  are bound, the separating element in the form of a bubble or Piston or a membrane and the respective fittings. In the gas part is a gas valve, preferably stick fabric, introduced according to the operating conditions. For a connection to the fluid circuit is on the fluid part of the A suitable fluid connection is provided in the pressure accumulator.

The manufacturing process of the previously known bubbles and Piston and diaphragm accumulator welded together with two The half-shells include the following procedure steps:

• 1. Connect a gas valve body to an upper storage tank partly by means of a MAG weld;
• 2. Connect a fluid port to the storage sub partly by means of a MAG weld;
• 3. Mount the separator in the lower part of the memory;
• 4. Mount the upper part of the storage unit on the lower part of the storage unit part;
• 5. Insert the merged storage group into one Device for welding a radial container seam; Suitable welding processes are: MAG welding, Laser welding, electron beam welding;
• 6. Insert the welded storage container into one further device for gas filling and closing of the gas space under pressure through a gas valve or Sealing washer with one screw.

The connection of the lower storage part with that of the customer The desired fluid connection is made at a very early stage stage (2nd step). This will make the Variety of types in planning, logistics, production and storage attitude very large, the lot size of the production inevitably small.

Fluid system manufacturers typically have own fluid connections that are not necessarily compatible with those from the manufacturer  the connections offered by the pressure accumulator match men. The manufacturers of fluid systems are reluctant to work other systems over, so that the manufacturer of storage containers tern when he is on a job for pressure accumulators with the available fluid connection types different fluid connections does not want to do without, even unprofitable small series in purchase must take. He is thus forced to store memory first equip parts with the desired fluid connection and this after inserting a separating element (bladder or piston or Membrane) finally with a corresponding upper spoke to be provided and welded with this in a pressure-tight manner sen.

So far, the fluid connections have been made using MAG welding has been attached to the lower part of the memory. Here is the Position of the weld seam on the lower part of the memory Shape of the fluid connection depends. The location of the sweat But seam has a direct influence on the shape strength of the storage tank. Therefore it is known manufacturing process a free choice of the fluid connection without considering the dimensional stability of the storage container Not possible together with the fluid connection.

The basic technical problem is that the An welding the fluid connection before inserting the sens Lichen separating element and therefore also before welding the Upper memory part must be made with the lower memory part. In front everything changes when the fluid connection is welded on the lower part of the memory in the area of the junction and ins especially the surfaces on the inside of the floor. For example, scale develops, which can be added later the separating element is inserted, can no longer eliminate. Any damage to the In adjacent to the welding area inner surfaces of the lower part of the memory can be damaged cause the separator. The during the welding process inevitably large heat development on the inside of the Lower memory part would be compulsory in a membrane memory  the destruction of the only partially thermally resilient Result in a membrane.

Therefore, the manufacturers of the pressure accumulator emphatically pointed out, no welding or soldering work on the welded accumulator.

It is the object of the invention to produce a method a bubble, piston or membrane memory and an on to develop direction for carrying out the method with which the disadvantages listed above, but in particular the logistical problems.

The invention provided to solve this problem The process is based on the knowledge that the manufacturer of Pressure storage an individual response to customer requests with respect to the type of fluid connection with a rational Manufacturing can connect, if a subsequent Attachment of the fluid connection or a uniform Fluid adapter on the storage container can be approved, without the separator already in the storage tank damaged by the welding process.

According to the invention, the object is achieved by the following method steps to make a bubble, piston or membrane memory solved:

• (a) Mount the partition member in the memory bottom part,
• (b) assembling the memory top and the memory lower part to a unit,
• (c) welding the lower part of the memory and the memory top to a pressure-tight storage container ter,
• (d) attaching the fluid port or a fluid adapters on the storage container by means of a suitable welding process.

The solution principle of the task is that of each desired fluid connection or the corresponding fluid adapter only after the completion of the storage tank, which is already equipped with a separating element, by means of a suitable welding process.

By using the method with the invention The manufacturer needs blister, piston or step sequence Membrane storage in future only after steps (a) to (c) manufactured storage containers in the usual sizes in terms of capacity and pressure range Keep stocks in connection with an appropriate number different types of fluid connections or one unit Chen type of fluid adapters to relatively at no extra cost short time bubble, piston or membrane memory with appro neten fluid connections to be supplied by the hydraulic manufacturer needs.

The subsequent attachment of the desired fluid connection or adapter (process step (d)) to the im remaining finished and pressure-tight storage containers can be done relatively easily and especially in the short term with a carry out suitable welding processes so that the series size has no decisive influence on the manufacturing costs Has.

Pressure welding is the most suitable welding process process into consideration. The friction is particularly advantageous welding. Here are rotationally symmetrical parts in one high-speed rotating device pressed together, the one Part is held while the other part rotates. After sufficient warming, the drive will close bes canceled and the parts are pressed together connected. This method is mainly suitable for small ones and medium rotationally symmetrical pipe cross sections or hollow bodies in small series production.  

A particular advantage of this method is that no filler materials are required that are too undefined lead transition zones with undefined microstructures. In contrast to the otherwise used metal active gas welding (MAG) is only a comparison in the friction welding process wise little effort necessary for the welding device.

Due to the space required by the usual equipment (welding head, preferably with feed device for the filler metal) So far, it has been necessary to carry out the MAG welding process also not possible to connect certain types of connection adapters to attach the lower part of the storage. This disadvantage does not apply when using the friction welding process, which is also the An allows welding of fluid adapters, where z. B. the pipe branch lines directly T-shaped from the fluid connections come off.

By using the friction welding process, it is also made possible a graded, defined transition a different material for a connector with other properties without additional filler materials to manufacture.

Another advantage of the friction welding process is that that in contrast to MAG welding no or at most ge slight changes to the inside surfaces of the storage container ters in the welding area. That is it justifies that the amount of scale, impurities formed gene and other reaction products significantly from the time of The influence of heat on the components is dependent. With the so far MAG welding is the welding time and therefore the Time of heat on the components is considerably larger than in friction welding. By filling the fluid part of the Storage container with the membrane pressed up with a ge The most suitable protective gas is the formation of scale and others Contamination reliably during the friction welding process and safely prevented.  

The friction welding process is compared to the usual Welding processes also cheaper.

Through this process, the thermal loads of the welding components is reduced, creating zones with undefi avoided structural changes or at least small-necked be. This also reduces the requirements the component contact geometries (for example, for elec Electrode beam welding requires quality IT 6 or IT 5 Lich, for the friction welding process only IT 9).

The result and quality of each weld are decisive from the process reliability of the individual Ferti step dependent. In friction welding are the ones flow and disturbance parameters in their quality and quantity meaning tends to be less than with MAG welding. Hence process is safety with reliable reproducibility when using the Friction welding process for the production of bubble, piston and Membrane save given.

Further advantageous embodiments of the invention are based the dependent claims and the following description.

Several embodiments of the invention are in the drawing are shown and are described in the following description exercise explained in more detail. Show it

Fig. 1.1 is a schematic representation of the method for producing a first embodiment of a bubble, piston or membrane memory with a gas welding butt closing the gas outlet opening;

FIG. 1.2 is a schematic representation of the procedure which according to FIG 1.1.

FIG. 2.1 is a schematic representation of the method for manufacturing a second embodiment of a bladder, piston or final Membranespeichers with a gas outlet opening, the gas valve body;

FIG. 2.2 is a schematic representation of the procedure which according to FIG 2.1.

Fig. 3 is a schematic representation of the procedural step "Attach the fluid port to the storage tank" according to Fig. 1.2 and 2.2 with the aid of a protective gas that can be conducted through a lance;

FIG. 4 shows a schematic illustration of an alternative method step compared to FIG. 3 "fastening the fluid connection to the storage container", with the aid of a protective gas which can be conducted through the fluid connection;

Fig. 5.1 is a sectional view of a third embodiment example of a membrane memory with a fluid adapter and a series of fluid connectors plugged into the fluid adapter;

Fig. 5.2 a continuation of the sectional view of the third embodiment according to Fig 5.1.

Figure 6 is a sectional view of a fourth embodiment example of a membrane memory with a fluid adapter and another series of fluid connections encompassing the fluid adapter;

Figure 7.1 is a sectional view of a fifth embodiment of an execution Membranespeichers Apter with a Fluidad and a series of fluid to the adapter to weldable fluid ports.

Fig. 7.2 a continuation of the sectional view of the fifth embodiment shown in Fig 7.2.

Fig. 8.1 sectional view of a sixth game Ausführungsbei a membrane memory with a series of weldable to the storage container fluid connections;

Fig. 8.2 a continuation of the sectional view of the sixth embodiment according to Fig. 8.1.

The process of making a bubble, piston or Membrane memory is based on an execution example of a membrane memory described.

A membrane memory consists essentially of a Spei cheroberteil 8 with a gas outlet opening 22 , a storage lower part 7 with a fluid opening 23 , a membrane 4 , a rigid valve plate 6 received by the membrane, a membrane retaining ring 5 holding the membrane 4 and one with the fluid opening 23rd connected fluid connection 11 .

In a first process step, the membrane 4 is slipped and vulcanized with its two ends over the membrane retaining ring 5 , so that the membrane 4 can be inserted in the lower part 7 in a dimensionally stable manner. Optionally, a valve plate 6 can be previously introduced and vulcanized into the lower part of the membrane 4 .

In the assembled position, the valve plate 6 is aligned with the fluid opening 23 , and the membrane retaining ring 5 bears against the inner wall of the lower storage part 7 , the upper storage part 8 forming a pre-assembled storage container 9 with the lower storage part 7 .

In a further method step, the assembled storage container 9 is welded in a pressure-tight manner by means of a known welding method (not shown in the drawing) at the seam formed by the connection point between the upper storage part 8 and the lower storage part 7 . The following welding methods are preferably used: MAG welding, laser welding, electron beam welding.

As soon as membrane memories with a certain fluid connection are needed, the next process step takes place, in which the pressure-tight storage container 9 is introduced into a first Spannvor device 19 and tensioned. Here, the storage container 9 is aligned so that the fluid opening 23 of the storage container 9 is axially aligned with the fluid opening 26 of the fluid connection 11 clamped in a second clamping device 20 . Preferably, the first clamping device 19 for the storage container 9 is rotatably, the second Spannvor direction 20 for the fluid connection 11 is rotatable. In this process step Ver, the fluid connection 11 by means of a press welding process, preferably by using the friction welding process on the pressure-tight storage container 9, is fixed.

The second clamping device 20 with the fluid connection 11 is rotated at high speed, one end of the fluid connection 11 being in engagement with the pressure-tight storage container 9 . After sufficient heating, the rotation is stopped and both parts are connected to each other by pressure.

It is preferable to avoid during friction welding operation under atmospheric conditions Protective gas used. In addition, the protective gas also for rapid cooling of the inner surface of the storage container used.

In the first exemplary embodiment ( FIGS. 1.1 and 1.2; "one-way version"), the pressure-tight storage container 9 is introduced into a tensioning device for gas filling and, after filling the gas space, is closed under pressure by means of a gas welding nozzle 13 . The following welding methods are preferably provided for attaching the gas welding nozzle 13 : resistance welding, MAG welding, capacitor discharge welding, friction welding.

In a second embodiment ( Fig. 2.1 and 2.2; "reusable version"), in which the game match with the first Ausführungsbei and illustrated in the drawing and used for the production process steps to avoid repetition are not described again, the pressure-tight storage container 9 together with the attached fluid port 11 in a third device 21 Spannvorrich introduced and directed against a clamped in a fourth clamping device 24 gas valve body 14 so that the opening 27 of the gas valve body 14 with the gas outlet opening 22 of the storage container 9 is axially aligned. To produce the attachment, the fourth clamping device 24 is preferably non-rotatable, whereas the third Spannvor direction 21 relative to the clamping device for the Speicherbe container 9 is rotatable. In this step, the gas valve body 14 is attached to the pressure-tight storage container 9 by means of a pressure welding process. A friction welding process is preferably also provided here.

For this purpose, the gas valve body 14 is set with the fourth Spannvor device 24 in high-speed rotations, wherein one end of the gas valve body 14 is in engagement with the storage container 9 . After sufficient heating, the rotation is stopped and both parts are connected to each other under pressure.

In a further method step, the pressure-tight storage container 9 with the gas valve body 14 is introduced into a further device for gas filling. After filling, the gas space is sealed and sealed by means of a screw 16 inserted into the gas valve body 14 with a corresponding seal 17 .

In a third exemplary embodiment ( FIGS. 5.1 and 5.2) - the large number of possibilities illustrated illustrates the versatility of the method according to the invention - a fluid adapter 25 is attached to the pressure-tight storage container 9 by means of the pressure welding method or another suitable welding method. This fluid adapter 25 has a nearly cylindrical shape, and is configured in its dimensions so that a fluid connection is pluggable into the fluid adapter 25 26th The fluid connection 26 is conically shaped at its end fitting into the fluid adapter 25 in order to ensure easy insertion of the fluid connection into the fluid adapter. The fluid connection 26 is finally welded to the fluid adapter 25 attached to the storage container 9 .

This embodiment is particularly suitable for pressure accumulators with high safety requirements, since on the one hand the conical connection part of the fluid connection 26 extends approximately to the fluid opening 23 of the storage container 9 and on the other hand for connecting the fluid adapter 25 to the fluid connection 26 in a sufficient range from within the Fluid connection 26 lying fluid line 28 can be welded.

In a fourth exemplary embodiment ( FIG. 6), which in turn comprises a large number of individual examples, a fluid adapter 30 is also attached to the pressure-tight storage container 9 by means of the pressure welding method or another suitable welding method. This fluid adapter 30 , however, has a conical connecting piece which is inserted into a correspondingly shaped fluid connection 31 and can be sealingly connected - preferably welded - to it.

In a fifth exemplary embodiment ( FIGS. 7.1 and 7.2), which in turn is illustrated by means of a large number of individual examples, a fluid adapter 40 of cylindrical, but essentially flat and flat shape is attached to the pressure-tight storage container 9 by means of the pressure welding method or another suitable welding method appropriate. A fluid connection 41 is attached to the free side of the fluid adapter 40 by means of a pressure welding process or another suitable welding process.

These embodiments (third to fifth game Ausführungsbei) are particularly suitable when it is not possible for reasons of an incompatible material pairing to attach the fluid connection 26 , 31 , 41 with the friction welding process directly to the storage container 9 . With the fluid adapter 25 , 30 , 40 , a gradual adaptation of the material of the storage container 9 to the material of the fluid connection is sufficient.

In a sixth embodiment ( Fig. 8.1 and 8.2), which in turn is illustrated by means of a large number of individual examples, a fluid connection 11 is directly connected to the pressure-tight storage container 9 , as already shown in FIGS . 1.1, 1.2, 2.1 and 2.2 the schematic representation of the method according to the invention is shown, attached by means of the pressure welding method.

Depending on the type of fluid connection, this method provides two options for bringing protective gas into the storage interior 15 of the storage container 9 during the welding process.

If the fluid line 28 of the fluid connection 11 , 26 , 31 , 41 is straight, it is suitable for introducing the protective gas into the storage interior 15 of the fluid part of the storage container 9, a lance 18 through the fluid opening 27 of the fluid connection 11 , 26 , 31 , 41 and the fluid opening 23 of the storage container 9 is guided into the storage interior 15 . The lance 18 pushes the membrane 4 away from the fluid opening 23 of the storage container 9 ( FIG. 3). The protective gas flows from openings 3 provided on the circumference of the lance 18 , preferably during the welding process, into the storage space 15 . This prevents, on the one hand, that the membrane is damaged during the welding process by the process-related heat development, on the other hand, by blowing protective gas into the storage space 15, excessive heat development and the processes usually occurring in this process under atmospheric pressure are avoided.

With T-shaped fluid connections, for example, are natural the requirements for the membrane position are the same.

With the help of a vacuum acting on the gas outlet opening 22 , the membrane is positioned in the storage container 9 and removed from the fluid opening 23 until the procedural heat generation for attaching the fluid connection to the storage container is not critical for the membrane consisting primarily of elastomer.

In order to maintain high process reliability here, too Location of the membrane via a centrally arranged switching pin (not shown in the drawing) monitored in the The interior of the storage tank scans the surface of the membrane. The associated switching elements are outside the facility arranged.

The protective gas which is advantageous for the welding process is supplied via a fluid line 27 'provided in the second clamping device 20 ' to the fluid opening 23 of the storage container 9 and thus introduced into the storage space 15 . The arrangement of the fluid line 27 'is adapted to the geometry of the respective fluid connection.

With the help of the described methods it is possible to Customer request appropriate fluid connections after completion the storage tank. Furthermore it is possible  equip the storage container with fluid connections, the were previously not attachable for geometric reasons because conventional welding processes are not suitable for this. In addition, this method is cheaper, which also Small series can be produced profitably.

Claims (14)

1. Method for producing a bubble, piston or membrane accumulator, which consists of an upper part of the accumulator, a lower part of the accumulator, a separating element (bladder or piston or diaphragm), a gas connection and a fluid connection, with the following process steps:

• (a) mounting the separating element in the lower storage part ( 7 ),
• (b) joining the upper storage part ( 8 ) and the lower storage part ( 7 ) into one unit,
• (c) welding the lower storage part ( 7 ) and the upper storage part ( 8 ) to a pressure-tight storage container ( 9 ) and
• (d) Attaching the fluid connection ( 11 ) to the storage container ( 9 ) by means of a suitable welding method.

2. The method according to claim 1, characterized in that the welding process for producing the attachment of the fluid connection ( 11 ) to the storage container ( 9 ) is a friction welding process. 3. The method according to claim 1 or claim 2, characterized in that to carry out the Reibschweißver method in a first clamping device ( 19 ) Liche storage container ( 9 ) and in a second clamping device ( 20 ) located fluid connection ( 11 ) with their Opening axes are aligned with each other and these are pressed against each other while executing a relative movement. 4. The method according to any one of claims 1 to 3, characterized in that during the friction welding process, the storage container ( 9 ) is filled with protective gas to avoid reactions and to cool the storage space ( 15 ). 5. The method according to claim 4, characterized in that the storage container ( 9 ) is filled by means of a lance ( 18 ). 6. The method according to any one of claims 1 to 4, characterized in that the separating element is positioned by means of the lance ( 18 ) in the storage container ( 9 ). 7. The method according to any one of claims 1 to 4, characterized in that the separating element is positioned on a gas outlet opening ( 22 ) of the storage container ( 9 ) acting vacuum in the storage container ( 9 ). 8. The method according to any one of claims 1 to 7, characterized in that the gas outlet opening ( 22 ) on the storage container ( 9 ) is closed by means of a gas welding nozzle ( 13 ). 9. The method according to any one of claims 1 to 7, characterized in that a gas valve body ( 14 ) is fastened above the gas outlet opening ( 22 ), which is fastened to the storage container ( 9 ) by means of a suitable welding method. 10. The method according to claim 9, characterized in that the welding process for producing the fastening of the gas valve body ( 14 ) with the storage container ( 9 ) is a friction welding process. 11. The method according to any one of the preceding claims, characterized in that instead of the fluid connection ( 11 ), a fluid adapter ( 25 , 30 , 40 ) is attached to the storage container ( 9 ), on which the desired fluid connection ( 26 , 31 , 41 ) can be attached. 12. Device for performing the method according to one of the preceding claims, characterized in that

• - For clamping the storage container ( 9 ) one of the shape of the storage container ( 9 ) corresponding first clamping device ( 19 ) and
• a second clamping device ( 20 ) corresponding to the shape of the fluid connection ( 11 ) is provided for tensioning the fluid connection ( 11 ),
• - The axis of the fluid opening ( 23 ) and the fluid connection ( 11 ) are the same axis and
• - The first clamping device ( 19 ) is rotatable relative to the second clamping device ( 20 ).

13. The device according to claim 11, characterized in that

• - For tensioning the storage container ( 9 ) together with the fluid connection ( 11 ) device a third Spannvorrich ( 21 ) and
• a fourth tensioning device ( 24 ) is provided for tensioning the gas valve body ( 14 ),
• - The axis of the gas outlet opening ( 22 ) and that of the gas valve body ( 14 ) are the same axis and
• - The fourth clamping device ( 24 ) for the third clamping device ( 21 ) is relatively rotatable.

14. Device according to one of the preceding claims, characterized in that the lance ( 18 ) is designed such that it can be passed through the fluid connection ( 11 ) and the fluid opening ( 23 ) of the storage container ( 9 ).