JP4178095B2 - Method for disassembling diaphragm valve and diaphragm valve used therefor - Google Patents

Description

  The present invention relates to a control valve disassembling method for controlling a fluid by bringing a valve body into contact with or separating from a valve seat, and a control valve used in the disassembling method.

  2. Description of the Related Art Conventionally, as a control valve that controls a fluid by bringing a valve body into contact with or away from a valve seat, for example, there is a chemical valve installed in a semiconductor manufacturing apparatus. An example of such a chemical valve is disclosed in Patent Document 1, and an example of a chemical valve that has the same basic structure and is publicly implemented is shown in FIGS. 9, 10, and 11. FIG. 9 is a cross-sectional view of a conventional chemical valve 100. FIG. 10 is a top view of a conventional chemical valve 100. FIG. 11 is a cross-sectional side view of a main part of a conventional chemical valve 100.

  The chemical valve 100 is obtained by connecting a body 101 and an actuator unit 102 with connecting screws 103, 103, 103, 103. The body 101 is provided with a valve seat 106 that allows the input port 104 and the output port 105 to communicate with each other. A piston rod 107 is slidably held on the actuator unit 102. The piston rod 107 protrudes from the lower end portion of the body 101 and is connected to the diaphragm 108. A pressing spring 109 is contracted on the actuator portion 102, and a force in the direction of the valve seat 106 is always applied to the piston rod 107. Therefore, in the chemical valve 100, while the operation fluid is not supplied to the operation port 110, the piston rod 107 is lowered to bring the diaphragm 108 into contact with the valve seat 106. On the other hand, when the operation fluid is supplied to the operation port 110, the chemical valve 100 moves up the piston rod 107 against the pressing spring 109 and separates the diaphragm 108 from the valve seat 106.

  In recent years, for example, some chemical liquids in semiconductor manufacturing apparatuses are mixed with an abrasive, and the chemical liquid valve 100 may control the chemical liquid. In this case, if the abrasive bites into the valve seat 106, fluid leakage may occur from the biting portion when the valve is closed. Therefore, the chemical solution valve 100 is subjected to maintenance for removing the connecting screw 103 to separate the actuator portion 102 from the body 101 and washing the body 101 and the valve seat 106. When the maintenance is completed, the chemical valve 100 is reassembled by placing the actuator portion 102 on the body 101 and passing the connecting screws 103... From the actuator portion 102 to the body 101 and fastening them.

JP 2001-153261 (paragraphs 0002 to 0006, FIG. 7).

  However, when the conventional control valve (chemical valve 100) is disassembled by loosening the connection screws 103 one by one, the force for pressing the actuator portion 102 against the body 101 becomes weak. The pressing spring 109 that is contracted to the actuator portion 102 has lost the balance of the elastic force applied to the piston rod 107 in an attempt to extend the connecting screw 103 in a loosening direction. Along with this, as shown in the cross-sectional view of FIG. 12, the actuator portion 102 is inclined with respect to the body 101 together with the piston rod 107. At this time, in the chemical valve 100, the operating fluid is not supplied to the operation port 110, and the diaphragm 108 is in contact with the valve seat 106. Therefore, as the actuator portion 102 is tilted, the diaphragm 108 may come into contact with the valve seat 106 and plastically deform the valve seat 106 (see portion A). If the valve seat 106 is plastically deformed even a little, the uniformity of the entire sealing force is lost, and there is a risk of fluid leakage from the plastically deformed portion, which is a problem.

  Therefore, the present invention has been made to solve the above problems, and provides a control valve disassembling method capable of disassembling a valve seat without plastic deformation, and a control valve used therefor. Objective.

In order to solve the above problems, the present invention has the following configuration.
(1) The body and the actuator are connected by a plurality of connecting screws, the valve body is held by the main shaft slidably held by the actuator, and the main body is urged by the urging means to valve the main body In the disassembling method of the control valve that contacts the valve seat provided in the body, the valve body is held in a state of being separated from the valve seat, and the plurality of connecting members are removed to separate the actuator from the body. And

(2) In the invention described in (1), an indicator member connected to the main shaft and slidably penetrating through a through hole formed in the actuator, and attached to the indicator member, and the indicator member is locked to the actuator A locking member to be moved, the main shaft is slid against the urging means, and the locking member is attached to the pointing member protruding from the penetration hole.

(3) The body and the actuator are connected by a plurality of connecting screws, the valve body is held by the main shaft slidably held by the actuator, and the main body is urged by the urging means to valve the main body The control valve that contacts the valve seat installed in the body has valve open state maintaining means for holding the valve body at a position separated from the valve seat when the fluid is not controlled. To do.

(4) In the invention described in (3), the valve open state maintaining means is connected to the main shaft, and protrudes to the outside from a through hole formed in the actuator when the main shaft slides against the biasing means. An indicator member, and a locking member that is attached to the indicator member and locks the indicator member to the actuator when the indicator member protrudes outside from the actuator.

Next, the function and effect of the invention having the above configuration will be described.
In the control valve, when the main shaft is urged in the valve seat direction by the urging means, the valve body comes into contact with the valve seat to shut off the fluid. On the other hand, when the main shaft slides in the actuator against the biasing means, the valve body separates from the valve seat. Such a control valve is disassembled as follows.

  The control valve is disassembled by holding the valve body at a position separated from the valve seat by the valve open state maintaining means, loosening and removing the connecting screws one by one, and removing the actuator from the body. At this time, as the connecting screw is loosened, the biasing force applied to the main shaft by the biasing means may be lost, and the actuator may tilt with respect to the body. However, since the valve body is separated from the valve seat, even if the actuator is inclined with respect to the body, the valve body does not come into contact with the valve seat, and the valve seat is not plastically deformed. Therefore, according to this invention, components can be disassembled without plastically deforming the valve seat.

  Further, the indicating member is connected to the main shaft that moves integrally with the valve body, and when the valve body is separated from the valve seat, the indicating member protrudes from the through hole of the actuator. Then, the locking member is attached to the indicating member protruding from the actuator. The indicating member tries to move in the valve seat direction by the urging force of the urging means that acts on the main shaft, but the movement of the indicating member is restricted by the actuator by the engaging member. Therefore, the main shaft connected to the indicating member and the valve body connected to the main shaft cannot move in the valve seat direction, and the valve open state is maintained. Therefore, according to the present invention, the valve opening state can be maintained simply by attaching the locking member to the indicating member protruding from the actuator when the valve is opened, so that plastic deformation of the valve seat can be easily prevented.

(First embodiment)
Next, a method for disassembling a control valve according to the present invention and a first embodiment of a control valve used therein will be described with reference to the drawings. FIG. 1 is a cross-sectional view of the chemical valve 1A, showing a closed state. FIG. 2 is a cross-sectional view of the chemical valve 1A and shows a valve open state.
The control valve of the present embodiment is a chemical liquid valve 1A that adjusts the flow rate of the chemical liquid, and is installed in, for example, a semiconductor manufacturing apparatus. The chemical liquid valve 1A is formed by connecting an actuator portion (corresponding to an “actuator”) 19A to a body 2 with a plurality of connecting screws (corresponding to “connecting members”) 21 (FIGS. 10 and 11). Reference), an air operated valve that causes the diaphragm 7 to abut against or separate from the valve seat 5 in accordance with a piston rod (corresponding to a “main shaft”) 10 provided in the actuator portion 19A.

  The body 2 is formed by molding a fluororesin such as PTFE (polytetrafluoroethylene) or PFA (tetrafluoroethylene perfluoroalkyl vinyl ether copolymer) into a block shape from the viewpoint of corrosion resistance and the like. An input port 3 and an output port 4 are formed in the body 2, and a valve seat 5 is integrally formed between the input port 3 and the output port 4. In the body 2, a cylinder 6A and a cover 8A are stacked, and four connecting screws 21 are passed from the cover 8A to the cylinder 6A, the body 2, and the mounting plate 16 (see FIGS. 10 and 11). The cylinder 6A, the cover 8A, and the mounting plate 16 are integrated. Thereby, the actuator portion 19 </ b> A is coupled to the body 2.

  A peripheral edge 7c of the diaphragm 7 is held between the body 2 and the cylinder 6A. The diaphragm 7 is formed by connecting a thick peripheral portion 7c to a cylindrical valve body portion 7a via a thin film portion 7b, and is arranged so that the valve body portion 7a contacts or separates from the valve seat 5. Has been.

  The cylinder 6A is formed in a cylindrical shape having a hollow hole, and a piston chamber 9 is formed between the cylinder 6A and the cover 8A. The piston chamber 9 is slidably loaded with a piston rod 10 and is hermetically partitioned into a primary chamber 9A and a secondary chamber 9B. An operation port 11 opened in the cylinder 6A communicates with the primary chamber 9A. The secondary chamber 9B communicates with an exhaust port 12 provided in the cover 8A, and a pressing spring (corresponding to an “urging means”) 13 is contracted so that the piston rod 10 always has a valve seat. Forces in 5 directions are applied. The piston rod 10 has a diaphragm 7 connected to a lower end portion, and applies a driving force in the vertical direction to the diaphragm 7 due to pressure fluctuations in the primary chamber 9A and the secondary chamber 9B.

  An indicator (corresponding to an “indicating member”) 14A penetrating through the cover 8A is screwed into the upper end of the piston rod 10 so that the indicator 14A can be taken in and out of the through hole 8a of the cover 8A. Yes. The indicator 14A is provided with a valve open state maintaining means 20 (see FIG. 2). The valve-opening state maintaining means 20 forms a through hole 14a in a direction orthogonal to the moving direction with respect to the indicator 14A, and a pin (corresponding to a “locking member”) 15 is formed in the through hole 14a exposed from the cover 8A. It is configured to penetrate through. The pin 15 is formed longer than the diameter of the penetration hole 8a formed in the cover 8A, and both ends are hooked and locked by the cover 8A.

  As shown in FIG. 1, such a chemical valve 1 </ b> A has a mounting plate 16 fixed to the lower end surface of the body 2. The mounting plate 16 is screwed to the semiconductor manufacturing apparatus, and the input port 3 and the output port 4. Are connected to the semiconductor manufacturing apparatus by connecting the pipes through the joints 17 and 18. The mounting plate 16 and the joints 17 and 18 are made of a fluororesin by injection molding from the viewpoint of corrosion resistance.

Next, the operation of the chemical valve 1A having the above configuration will be described.
When the operation fluid is not supplied from the operation port 11 to the primary chamber 9A, the piston rod 10 is pushed down by the pressing spring 13 and the valve body portion 7a of the diaphragm 7 is brought into contact with the valve seat 5 as shown in FIG. Let Therefore, the chemical solution supplied to the input port 3 is not output from the output port 4. At this time, the indicator 14A is housed in the actuator portion 19A.

  On the other hand, when supplying the operation fluid from the operation port 11 to the primary chamber 9A, as shown in FIG. 2, the piston rod 10 rises against the pressing spring 13, and the valve body portion 7a of the diaphragm 7 is moved to the valve seat. 5 apart. Therefore, the chemical solution supplied to the input port 3 is output to the output port 4 at a flow rate corresponding to the valve opening. At this time, since the indicator 14A protrudes from the cover 8A in response to the rise of the diaphragm 7, the operator can check the opened state of the chemical valve 1A from the protruding amount of the indicator 14A.

  By the way, when the chemical liquid valve 1A controls the chemical liquid by repeatedly opening and closing the valve, foreign substances (dust) contained in the chemical liquid may bite into the valve seat 5, and the chemical liquid may leak from the biting part of the foreign substances when the valve is closed. is there. In particular, when the chemical valve 1 </ b> A controls a slurry mixed with an abrasive or the like, foreign substances are likely to bite into the valve seat 5. Therefore, it is necessary to remove foreign matters (dust) or to check for foreign matter bites. Maintenance of the chemical liquid valve 1A is performed as follows.

First, the chemical valve 1A is disassembled.
Specifically, as shown in FIG. 1, the supply of the chemical solution is stopped, and the operation fluid is supplied from the operation port 11 of the actuator unit 19A to the primary chamber 9A. When the pressure in the primary chamber 9 </ b> A overcomes the elastic pressure of the pressing spring 13, as shown in FIG. 2, the piston rod 10 rises and the valve body portion 7 a of the diaphragm 7 is separated from the valve seat 5. Therefore, the valve body portion 7a of the diaphragm 7 is held at a position separated from the valve seat 5 by the valve open state maintaining means 20.

  The indicator 14A protrudes from the penetration hole 8a of the cover 8A as the piston rod 10 is lifted, and the through hole 14a is exposed to the outside of the cover 8A, so that the pin 15 penetrates the through hole 14a of the indicator 14A. Thereafter, the pipe connected to the operating fluid drive source is removed from the operating port 11, and the supply of the operating fluid from the operating port 11 to the primary chamber 9A is stopped. The piston rod 10 is urged by the pressing spring 13 to lower, but as shown in FIG. 3, both end portions of the pin 15 are caught by the cover 8A, and the indicator 14A is locked to the actuator portion 19A. Restricts movement in the direction of the valve seat 5. Accordingly, the piston rod 10 screwed to the indicator 14A and the valve body portion 7a of the diaphragm 7 screwed to the piston rod 10 are restricted from moving in the direction of the valve seat 5, and the valve open state is maintained.

  Then, the connecting screw 21 penetrating through the cover 8A, the cylinder 6A, and the body 2 is loosened and removed. In the chemical valve 1A, the elastic force of the pressing spring 13 acts on the piston rod 10 evenly while the four connecting screws 21 are fastened. However, as shown in FIG. 4, when one of the connecting screws 21 is loosened, the force for pressing the actuator portion 19 </ b> A against the body 2 is weakened. Along with this, the pressing spring 13 tends to extend, so the balance of the elastic force acting on the piston rod 10 is lost. However, at this time, since the other three connecting screws 21, 21, 21 connect the actuator portion 19A and the body 2, even if the balance of the elastic force acting on the piston rod 10 is slightly lost, The inclination of the actuator portion 19A is suppressed. However, even if one of the connecting screws 21 is loosened and the actuator portion 19 </ b> A is slightly inclined, the valve body portion 7 a of the diaphragm 7 is separated from the valve seat 5. Therefore, the valve body portion 7a of the diaphragm 7 does not come into contact with the valve seat 5 to plastically deform the valve seat 5.

  Thereafter, as shown in FIG. 5, when the other connecting screw 21 is loosened, the force for pressing the actuator portion 19A against the body 2 is suddenly weakened. As the connecting screw 21 is loosened, the pressing spring 13 tends to extend between the cover 8A and the piston rod 10, and the balance of the elastic force applied to the piston rod 10 is lost. The actuator portion 19 </ b> A tilts with respect to the body 2 together with the piston rod 10 in accordance with the unbalance of the elastic force of the pressing spring 13, and tilts the diaphragm 7 with respect to the valve seat 5. However, at this time, the diaphragm 7 is separated from the valve seat 5 in the valve body portion 7a. Therefore, even if the diaphragm 7 is inclined with respect to the valve seat 5, the valve body portion 7 a of the diaphragm 7 does not come into contact with the valve seat 5 to plastically deform the valve seat 5.

  When all the connecting screws 21 are removed, the actuator portion 19A is detached from the body 2 and separated as shown in FIG. At this time, the pin 15 locks the indicator 14A to the cover 8A and restricts the movement of the piston rod 10, so that the pressing spring 13 is compressed and held between the cover 8A and the piston rod 10. Therefore, when the actuator portion 19A is removed from the body 2, the piston rod 10, the pressing spring 13, and the like do not jump out of the cylinder 6A and become separated.

Next, the body 2 is cleaned and parts are inspected.
When the actuator portion 19A is removed from the body 2, the diaphragm 7 is also removed integrally with the piston rod 10, and the valve seat 5 and the flow path are exposed. Therefore, the dirt adhering to the body 2 and the valve seat 5 is washed away, and the seal surface is checked for scratches. For example, when the diaphragm 7 has deteriorated, it is replaced with a new diaphragm. At this time, the actuator portion 19A has the pin 15 inserted into the through hole 14a of the indicator 14A to prevent the piston rod 10 from falling off the cylinder 6A. Therefore, the actuator portion 19A is not separated, and the diaphragm 7 Can be exchanged.

Next, the chemical valve 1A is reassembled.
The actuator portion 19A is placed on the body 2 so as to sandwich the peripheral edge portion 7c of the diaphragm 7. Then, the connecting screws 21 are passed through and fastened to the four corners of the actuator portion 19A, the body 2, and the mounting plate 16 to connect the cover 8A, the cylinder 6A, the body 2, and the mounting plate 16. At this time, since the pin 15 is passed through the indicator 14A, the piston rod 10 and the like are not held apart by the cylinder 6A, and the parts can be easily reassembled. In addition, since the state where the diaphragm 7 is separated from the valve seat 5 is maintained, even if the piston rod 10 is inclined when the connecting screw 21 is fastened, the valve body portion 7a of the diaphragm 7 hits the valve seat 5 in one piece. The valve seat 5 is not plastically deformed.

Therefore, in the method of disassembling the chemical valve 1A of the present embodiment, the valve body portion 7a of the diaphragm 7 is held in a state of being separated from the valve seat 5, the plurality of connecting members 21 are removed, and the actuator portion 19A is removed from the body 2. Since they are separated, the parts can be disassembled without plastically deforming the valve seat 5.
In particular, the piston rod 10 is slid against the pressing spring 13 and the valve 15 is maintained by passing the pin 15 through the indicator 14A protruding from the penetration hole 8a. can do. In addition, since it is not necessary to supply the operation fluid to the operation port 11 and separate the valve body portion 7a of the diaphragm 7 from the valve seat 5 at the time of disassembly, the parts can be easily disassembled.

Further, the chemical valve 1A of the present embodiment has the valve open state maintaining means 20 that holds the valve body portion 7a of the diaphragm 7 at a position separated from the valve seat 5, so that the valve seat 5 is not plastically deformed. Parts can be disassembled.
In particular, the valve opening maintaining means 20 is connected to the piston rod 10, and when the piston rod 10 slides against the pressing spring 13, an indicator 14 </ b> A that protrudes outside from a through hole 8 a formed in the actuator portion 19 </ b> A. And the pin 15 that passes through the through hole 14a of the indicator 14A and locks the indicator 14A to the actuator portion 19A when the indicator 14A protrudes outside from the actuator portion 19A. Plastic deformation can be prevented. Moreover, since the conventional indicator 14A has a compact structure in which the through hole 14a is provided to penetrate the pin 15, the manufacturing is easy and the manufacturing cost can be reduced.

(Form of reference example )
Next, a method for disassembling a control valve according to the present invention and a reference example of a control valve used for the method will be described with reference to the drawings. FIG. 7 is a cross-sectional view of the chemical valve 1B. FIG. 8 is a top view of the chemical valve 1B.
The chemical valve 1B of the present embodiment has the same basic structure as the chemical valve 1A of the first embodiment, but the first embodiment is that the cylinder 6B and the cover 8B are integrated with a fixing screw 30. This is different from the chemical liquid valve 1A. Therefore, here, the description will focus on the configuration and operational effects different from those of the first embodiment, and the same reference numerals are given to the same configurations as those of the first embodiment, and the description thereof will be omitted as appropriate.

  The chemical valve 1B constitutes an actuator assembly (corresponding to an “actuator”) 19B in which the cylinder 6B and the cover 8B are connected by a pair of fixing screws 30 and 30 and can be assembled as a single actuator. The pair of fixing screws 30 and 30 are provided at symmetrical positions across the indicator 14B. The pair of fixing screws 30 are arranged symmetrically in order to equalize the force that holds the cylinder 6B against the cover 8B. The fixing screw 30 is passed through from the lower end surface of the cylinder 6B (the surface contacting the body 2) toward the cover 6B and fastened. Fastening the fixing screw 30 from the lower end surface side of the cylinder 6B avoids loosening the fixing screw 30 accidentally with the connecting screw 21 when the chemical valve 1B is disassembled, and ensures a wide screwing area of the fixing screw 30. This is to connect the cylinder 6B and the cover 8B against the elastic force of the pressing spring 13.

Such a chemical valve 1B is disassembled as follows.
First, the operation fluid is supplied to the operation port 11 of the chemical liquid valve 1 </ b> B, and the valve body 7 a of the diaphragm 7 is separated from the valve seat 5. Then, while supplying the operation fluid to the operation port 11, the connection screw 21 is loosened and removed, and the actuator assembly 19 </ b> B is separated from the body 2.
At this time, since the fluid pressure of the operating fluid acts on the lower end surface of the piston rod 10, the pressing spring 13 is compressed and tries to push up the cover 8B from the cylinder 6B. However, since the fixing screw 30 connects the cylinder 6B and the cover 8B, the actuator assembly 19B does not fall apart when the chemical valve 1B is disassembled.

Therefore, according to the disassembling method of the chemical valve 1B of the present embodiment, by supplying the operation fluid to the operation port 11, the valve body portion 7a of the diaphragm 7 is held at a position away from the valve seat 5, and the connecting screw 21 Is removed and the actuator assembly 19B is removed from the body 2, so that the parts can be disassembled without plastically deforming the valve seat 5.
Further, since the chemical valve 1B connects the cylinder 6B and the cover 8B with the fixing screw 30 and supplies the operation fluid to the operation port 11, the diaphragm 7 is held at a position separated from the valve seat 5, so that the first Although the apparatus size is larger than the chemical liquid valve 1A of the embodiment, the parts can be disassembled without plastically deforming the valve seat 5.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various applications are possible.

(1) For example, in the first embodiment, the valve open state maintaining means 20 is configured to insert the pin 15 through the indicator 14A. On the other hand, a branch or an E-ring may be attached to the indicator 14A and locked to the cover 8A. Further, a male screw may be formed on the outer peripheral surface of the upper end portion of the indicator 14A, and a nut having a female screw formed on the inner periphery may be screwed into the indicator 14A.

(2) For example, in the said 1st Embodiment and the form of a reference example, although chemical | medical solution valve 1A, 1B used for a semiconductor manufacturing apparatus as a control valve was demonstrated, the use application of a control valve is not limited to this.

It is sectional drawing of a chemical | medical solution valve concerning 1st Embodiment of this invention, Comprising: A valve closing state is shown. Similarly, it is sectional drawing of a chemical | medical solution valve, Comprising: The state before pin insertion which supplied the operation fluid is shown. Similarly, it is sectional drawing of a chemical | medical solution valve, Comprising: The state after pin insertion which does not supply the operation fluid is shown. Similarly, it is sectional drawing of a chemical | medical solution valve, Comprising: The state which loosened one of the connection screws is shown. Similarly, it is sectional drawing of a chemical | medical solution valve, Comprising: The state which loosened the other connection screw is shown. Similarly, it is sectional drawing of a chemical | medical solution valve, Comprising: The state which isolate | separated the actuator part from the body is shown. It is sectional drawing of a chemical | medical solution valve concerning the form of the reference example of this invention. Similarly, it is a top view of a chemical valve. It is sectional drawing of the conventional chemical | medical solution valve. It is a top view of the conventional chemical | medical solution valve. It is a principal part cross-sectional side view of the conventional chemical | medical solution valve. It is sectional drawing of the conventional chemical | medical solution valve, Comprising: The state which loosened the connection screw is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1A Chemical liquid valve 1B Chemical liquid valve 2 Body 5 Valve seat 7 Diaphragm 8a Penetration hole 10 Piston rod 14A Indicator 15 Pin 19A Actuator part 19B Actuator assembly 20 Valve open state maintenance means 21 Connection screw 30 Fixing screw

Claims (2)

A body and an actuator are connected by a plurality of connecting screws, the valve body is held by a main shaft slidably held by the actuator, and the main body is urged by an urging means. In the disassembling method of the diaphragm valve in which the valve abuts on the valve seat provided in the body,
An indicator member coupled to the main shaft and slidably penetrating through a through hole formed in the actuator;
A locking member mounted on the pointing member and locking the pointing member to the actuator;
In a state where the valve body is separated from the valve seat by sliding the main shaft against the biasing means and attaching the locking member from the outside to the indicating member protruding from the penetration hole. Holding and removing the plurality of connecting screws to separate the actuator from the body together with the diaphragm without touching the diaphragm connected to the actuator;
A method for disassembling a diaphragm valve. A body and an actuator are connected by a plurality of connecting screws, the valve body is held by a main shaft slidably held by the actuator, and the main body is urged by an urging means. In a diaphragm valve that abuts against a valve seat provided in the body,
When maintaining the valve open state, it is connected to the main shaft, the main shaft slides against the biasing means, and the penetration formed in the actuator when the valve body is separated from the valve seat An indicator member protruding outward from the hole;
And a valve-opening state maintaining means provided with a locking member that is attached to the pointing member and locks the pointing member from the outside when the pointing member protrudes from the actuator. Diaphragm valve.

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