A bellows-sealed regulating valve

Abstract

This utility model discloses a bellows-sealed regulating valve comprising: a valve body having a through medium channel, the medium channel having a flow inlet and a flow outlet, and a receiving port on the top of the valve body communicating with the medium channel; a valve cover, located on the top of the valve body and covering the receiving port; a rocker arm, rotatably mounted on the valve cover by means of a first bushing; a rocker rod, the rocker rod passing through the receiving port, with its first end fixedly mounted on the rocker arm and its second end extending into the medium channel, the second end of the rocker rod being fitted with a valve disc for sealing or opening the flow inlet and flow outlet; a bellows, the upper end of the bellows being sealed and welded to the bottom surface of the rocker arm, and the lower end of the bellows being sealed and welded to the inner circumferential wall of the receiving port; and an actuator for laterally pushing the rocker arm to swing around the axis of the first bushing, thereby driving the rocker rod and valve disc to move. This utility model can solve the problem that traditional ordinary disc valves do not have the function of bellows sealing, which limits the application of disc valves in toxic and harmful working conditions.

Description

Technical Field

[0001] This utility model relates to the field of regulating valves, specifically to a bellows-sealed regulating valve. Background Technology

[0002] With industrial development, solid-containing applications are becoming increasingly common, such as polysilicon production, coal gasification, and coal-to-oil processes, placing higher demands on valves. The unique self-grinding function of the hard sealing surface of disc valves continuously improves their sealing performance and extends their service life compared to other valves when used with abrasive or erosive materials.

[0003] Bellows-sealed valves are suitable for pipelines carrying hazardous media such as steam, flammable, explosive, heat transfer oil, toxic substances, and molten salts. The bellows seal design effectively blocks the flow of the medium while retaining the original valve stem packing structure. This double-sealing structure ensures reliability at the valve stem. Therefore, bellows-sealed valves are widely used in industries such as petroleum, chemical, natural gas, optoelectronics, and nuclear power.

[0004] Because the closing element of a disc valve is a swing mechanism, the valve stem rotates. Ordinary disc valves without bellows seals limit their application in toxic or hazardous environments. Utility Model Content

[0005] To overcome the above-mentioned shortcomings, the purpose of this utility model is to provide a bellows-sealed regulating valve.

[0006] To achieve the above objectives, the technical solution adopted by this utility model includes:

[0007] A valve body has a through-flow medium channel with an inlet and an outlet. A receiving port communicating with the medium channel is located at the top of the valve body. A valve cover is located at the top of the valve body and covers the receiving port. A rocker arm is rotatably mounted on the valve cover via a first bushing, the axis of which is parallel to the axis of the medium channel. A rocker rod has a first end and a second end, passing through the receiving port. The first end is fixedly mounted on the rocker arm, and the second end extends into the medium channel. A valve disc for sealing or opening the inlet and outlet of the medium channel is mounted on the second end of the rocker rod. A bellows has its upper end sealed and welded to the bottom surface of the rocker arm, and its lower end sealed and welded to the inner circumferential wall of the receiving port. An actuator is located on the valve cover and is used to laterally push the rocker arm to swing around the axis of the first bushing, thereby moving the rocker rod and the valve disc to control the opening and closing of the inlet and outlet of the medium channel.

[0008] In the preferred embodiment of the bellows-sealed regulating valve described above, the actuator includes a valve stem that is threaded laterally onto the valve cover. The valve stem has a sleeve end and a handle end. The sleeve end extends into the valve cover and has an opening on the side facing the rocker arm. An extension formed on the upper part of the rocker arm extends into the sleeve end of the valve stem through the opening. When the valve stem moves laterally relative to the valve cover, the extension moves within the sleeve end to push the rocker arm to swing around the axis of the first bushing.

[0009] In the preferred embodiment of the bellows-sealed regulating valve described above, the extension is a shaft head rotatably mounted on the side of the rocker arm via a second bushing and a spindle. The spindle is rotatably mounted inside the second bushing, and the shaft head is rotatably mounted on the spindle. The axial direction of the second bushing is parallel to the axial direction of the medium channel.

[0010] In the preferred embodiment of the bellows-sealed regulating valve described above, the second bushing is an eccentric bushing, which is rotatable relative to the rocker arm and fixedly mounted on the rocker arm by means of a locking element.

[0011] In the preferred embodiment of the bellows-sealed regulating valve described above, the locking element is a circular sawtooth structure that rotates synchronously with the second bushing and a buckle provided on the rocker arm that can extend into the tooth groove of the sawtooth structure.

[0012] In the preferred embodiment of the bellows-sealed regulating valve described above, a plurality of rolling elements are installed between the shaft head and the spindle, which are evenly arranged around the central axis of the shaft head.

[0013] In the preferred embodiment of the bellows-sealed regulating valve described above, the valve disc includes a first sealing portion and a second sealing portion symmetrically arranged on both sides of the second end of the rocker arm along the axial direction of the medium channel, and the first sealing portion and the second sealing portion are connected by an elastic element.

[0014] In the preferred embodiment of the bellows-sealed regulating valve described above, both the flow channel inlet and the flow channel outlet are recessed into the medium channel to form a boss. Along the swing direction of the valve disc, at least one guide rib is provided in the medium channel that is flush with the surface of the boss.

[0015] In the preferred embodiment of the bellows sealing regulating valve described above, the central axis of the first bushing is located at the middle position of the bellows.

[0016] In the preferred embodiment of the bellows-sealed regulating valve described above, the bellows is made of stainless steel and the wall thickness of the bellows is 0.3-0.9 mm. Attached Figure Description

[0017] Figure 1 This is the front view of the present invention;

[0018] Figure 2 A schematic diagram of the internal structure of the valve body and valve cover after being cut open;

[0019] Figure 3 A cross-sectional view of this utility model Figure 1 ;

[0020] Figure 4 A cross-sectional view of this utility model Figure 2 ;

[0021] Figure 5 A cross-sectional view of this utility model Figure 3 ;

[0022] Figure 6 Diagram showing the connection between the actuator and the rocker arm;

[0023] Figure 7 This is a schematic diagram of the actuator.

[0024] Figure 8 This is a diagram showing the connection relationship between some of the actuators and the rocker arm;

[0025] Figure 9 This is a schematic diagram of a rocker arm;

[0026] Figure 10 This is a cross-sectional view of the rocker arm;

[0027] In the diagram: Valve body 1, medium channel 101, flow channel inlet 102, flow channel outlet 103, receiving port 104, valve cover 2, rocker arm 3, first bushing 4, rocker rod 5, valve disc 6, first sealing part 61, second sealing part 62, bellows 7, actuator 8, valve stem 81, sleeve end 811, opening 8111, handle end 812, second bushing 91, spindle 92, shaft head 93, rolling element 94, serrated structure 111, snap fastener 112, side cover 12, filling hole 121, ear plate 131, pressure sleeve 132, disc spring 133, elastic element 14, boss 15, guide rib 16. Detailed Implementation

[0028] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0029] It should be noted that in the description of this utility model, terms such as "upper," "lower," "left," "right," "front," and "rear," which indicate direction or positional relationships, are based on the direction or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0030] Furthermore, it should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0031] like Figures 1 to 10 As shown, the bellows-sealed regulating valve of this utility model includes: a valve body 1 having a through medium channel 101, the medium channel 101 having a flow inlet 102 and a flow outlet 103, and a receiving port 104 communicating with the medium channel 101 at the top of the valve body 1; a valve cover 2, disposed at the top of the valve body 1 and covering the receiving port 104; a rocker arm 3, rotatably mounted on the valve cover 2 by means of a first bushing 4, the axis of the first bushing 4 being parallel to the axis of the medium channel 101; and a rocker rod 5 having a first end and a second end, the rocker rod 5 passing through the receiving port 104. 4. The first end is fixedly mounted on the rocker arm 3, and the second end extends into the medium channel 101. The second end of the rocker arm 5 is equipped with a valve disc 6 for sealing or opening the flow channel inlet 102 and the flow channel outlet 103. The upper end of the bellows 7 is sealed and welded to the bottom surface of the rocker arm 3, and the lower end of the bellows 7 is sealed and welded to the inner circumferential wall of the receiving port 104. The actuator 8 is located on the valve cover 2 and is used to laterally push the rocker arm 3 to swing around the axis of the first bushing 4, thereby driving the rocker arm 5 and the valve disc 6 to move, so as to realize the opening and closing control of the flow channel inlet 102 and the flow channel outlet 103.

[0032] See Figures 1 to 3The lower part of the valve body 1 has a through medium channel 101. The inlet of the medium channel 101 is the flow inlet 102, and the outlet of the medium channel 101 is the flow outlet 103. A receiving port 104 opened at the top of the valve body 1 connects the medium channel 101 to the outside of the valve body 1. A valve cover 2 with a frame-shaped cross-section is installed at the top of the valve body 1. The valve cover 2 surrounds the receiving port 104. A first bushing 4 is rotatably installed on the valve cover 2 along the central axis of the medium channel 101 or the flow inlet 102 and the flow outlet 103. The rocker arm 3 is rotatably mounted inside the valve cover 2 by means of a bushing. The rocker arm 5 has a first end and a second end. The first end of the rocker arm 5 is fixed on the rocker arm 3. The rocker arm 5 passes through the receiving port 104 and places the second end in the medium channel 101. The second end of the rocker arm 5 is equipped with a valve disc 6 that is adapted to the flow channel inlet 102 and the flow channel outlet 103. When the rocker arm 5 swings with the rocker arm 3, the valve disc 6 can block or open the flow channel inlet 102 and the flow channel outlet 103 to control the flow of fluid in the medium channel 101.

[0033] See Figure 2 , Figure 3 The upper end of the bellows 7 is welded to the bottom surface of the rocker arm 3, and the lower end of the bellows 7 is welded to the inner circumferential wall of the accommodating port 104 of the valve body 1. The rocker arm 5 is located inside the bellows 7, so that the medium channel 101 is connected to the inside of the bellows 7 and not connected to the internal space of the valve cover 2. With this arrangement, the regulating valve of this application can be used in toxic and harmful working conditions, avoiding the possibility of leakage of toxic and harmful substances, and improving the application effect and scope of application of this application.

[0034] See Figure 1 , Figure 4 The actuator 8 is located on the side of the valve cover 2 along the direction perpendicular to the central axis of the medium channel 101. The actuator 8 can reciprocate to push the upper part of the rocker arm 3 along the direction perpendicular to the central axis of the medium channel 101, causing the rocker arm 3 to swing along the central axis of the first bushing 4. This causes the rocker arm 3 to drive the rocker rod 5 to swing, so that the valve disc 6 at the second end of the rocker rod 5 blocks or opens the flow channel inlet 102 and the flow channel outlet 103. It can be understood that since the rocker rod 5 is always inside the bellows 7 and the medium channel 101, the fluid in the medium channel 101 will not flow out into the valve cover 2 through the accommodating port 104, which effectively improves the sealing effect of this application and enables the regulating valve of this application to adapt to the usage requirements under different working conditions, especially in the environment of conveying toxic and harmful substances. In addition, it should be noted that when the actuator 8 drives the rocker arm 3 to swing, the bellows 7 will deform synchronously to adapt to the movement of the rocker arm 3.

[0035] In one or more embodiments, the actuator 8 includes a valve stem 81 that is laterally threaded onto the valve cover 2. The valve stem 81 has a sleeve end 811 and a handle end 812. The sleeve end 811 extends into the valve cover 2 and has an opening 8111 on the side facing the rocker arm 3. An extension formed on the upper part of the rocker arm 3 extends into the sleeve end 811 of the valve stem 81 through the opening 8111. When the valve stem 81 moves laterally relative to the valve cover 2, the extension moves within the sleeve end 811 to push the rocker arm 3 to swing about the axis of the first bushing 4.

[0036] See Figures 1 to 7 The valve stem 81 has a sleeve end 811 and a handle end 812. The valve stem 81 is threaded onto the side of the valve cover 2 in a direction perpendicular to the axis of the medium channel 101. The handle end 812 has a round handle that facilitates the user to rotate the valve stem 81. The cross-section of the sleeve end 811 in the height direction is an inverted U-shaped structure. The sleeve end 811 of the valve stem 81 has an opening 8111 on the side facing the extension of the rocker arm 3. The extension can extend into the opening 8111 and its movement is restricted by the internal shape of the sleeve end 811.

[0037] Specifically, when the actuator 8 controls the rocker arm 3 and the rocker rod 5 to swing, by rotating the handle end 812 of the valve stem 81 clockwise or counterclockwise, the sleeve end 811 of the valve stem 81 moves laterally within the valve cover 2 along a direction perpendicular to the central axis of the first bushing 4. The extension of the rocker arm 3 located within the sleeve end 811 is pushed by the valve stem 81 and moves up or down within the U-shaped channel of the sleeve end 811 of the valve stem 81, thereby causing the rocker arm 3 to swing around the central axis of the first bushing 4. The rocker arm 3 drives the rocker rod 5 to swing, causing the valve disc 6 installed at the second end of the rocker rod 5 to block or open the flow channel inlet 102 and the flow channel outlet 103. While the rocker arm 3 swings, it can press the bellows 7 to deform. With the help of the sealing effect of the bellows 7, the medium channel 101 will not be connected to the inside of the valve cover 2 during the swing of the rocker rod 5, thereby improving the sealing effect of this application.

[0038] In one or more embodiments, the extension is a shaft head 93 rotatably mounted on the side of the rocker arm 3 via a second bushing 91 and a spindle 92. The spindle 92 is rotatably mounted inside the second bushing 91, and the shaft head 93 is rotatably mounted on the spindle 92. The axial direction of the second bushing 91 is parallel to the axial direction of the medium channel 101. A plurality of rolling elements 94 are installed between the shaft head 93 and the spindle 92, which are evenly arranged around the central axis of the shaft head 93.

[0039] See Figures 7 to 10The extension includes a second bushing 91, a spindle 92, and a shaft head 93. The second bushing 91 is mounted on the upper part of the rocker arm 3 along a direction parallel to the axis of the medium channel 101. The spindle 92 is rotatably mounted inside the second bushing 91. The shaft head 93 is rotatably mounted on the spindle 92 via a rolling element 94, which can be a ball or needle roller. This method reduces the friction of the shaft head 93 within the U-shaped channel of the valve stem 81 sleeve end 811, facilitating the rotation of the shaft head 93. This improves the smoothness of rocker arm 3 swinging; the shaft head 93 is placed in the U-shaped channel of the valve stem 81 sleeve end 811, and the outer surface of the shaft head 93 abuts against the inner wall of the U-shaped channel of the sleeve end 811. When the valve stem 81 sleeve end 811 moves in a direction perpendicular to the axis of the first bushing 4, the shaft head 93 is restricted by the U-shaped channel of the sleeve end 811 and moves vertically up or down in the U-shaped channel of the valve stem 81 sleeve end 811, thereby driving the rocker arm 3 to swing around the axis of the first bushing 4.

[0040] See Figure 7 It should be noted that the sleeve end 811 at the second end of the valve stem 81 is rotatably connected to the stem body of the valve stem 81. When the valve stem 81 rotates relative to the valve cover 2, the sleeve end 811 will not rotate circumferentially with the valve stem 81 due to the restriction of the shaft head 93, thus ensuring the stability of the connection between the shaft head 93 and the sleeve end 811 of the valve stem 81 and realizing the smooth swing of the rocker arm 3.

[0041] In one or more embodiments, the second bushing 91 is an eccentric bushing, which is rotatable relative to the rocker arm 3 and fixedly mounted on the rocker arm 3 by means of a locking member; the locking member is a circular sawtooth structure 111 that rotates synchronously with the second bushing 91 and a buckle 112 provided on the rocker arm 3 and capable of extending into the tooth groove of the sawtooth structure 111.

[0042] See Figures 7 to 10 A circular sawtooth structure 111 is fixedly installed on the second bushing 91, and a buckle 112 is detachably installed on the rocker arm 3. The buckle 112 can enter the tooth groove of the sawtooth structure 111 to limit the sawtooth structure 111, thereby fixing the second bushing 91 on the rocker arm 3.

[0043] It is understandable that, due to certain errors in the processing or assembly of the valve disc 6 and valve stem 81 within the regulating valve of this application, the initial position of the valve disc 6 needs to be adjusted in order to effectively drive the valve disc 6 to seal the flow channel inlet 102 and flow channel outlet 103. Specifically, since the second bushing 91 is an eccentric bushing, the initial swing position of the rocker arm 3 can be adjusted by rotating the second bushing 91 clockwise or counterclockwise to drive the rocker arm 3 to make a slight deflection, thereby adjusting the initial position of the valve disc 6 and improving the sealing degree of the valve disc 6 in sealing the flow channel inlet 102 and flow channel outlet 103. After the second bushing 91 is adjusted, the buckle 112 is fastened into the tooth groove of the sawtooth structure 111 and fixed on the rocker arm 3, thus fixing the position of the second bushing 91 after adjustment.

[0044] In one specific embodiment, a side cover 12 is bolted to the connection between the valve cover 2 and the valve stem 81. A through hole is provided on the side cover 12 along the axial direction of the valve stem 81. The valve stem 81 passes through the through hole and extends into the valve cover 2. A filling hole 121 is provided around the through hole. The filling hole 121 is filled with sealing packing. A clamping structure is installed on the side cover 12. The clamping structure is used to clamp the sealing packing into the filling hole 121.

[0045] See Figures 1 to 7 The clamping structure includes at least an ear plate 131 formed on the side cover 12, a pressure sleeve 132 disposed on the ear plate 131 near the valve cover 2, and a disc spring 133 connecting the ear plate 131 and the side cover 12. The pressure sleeve 132 can extend into the filling hole 121. With the help of the elastic force of the disc spring 133, the ear plate 131 and the pressure sleeve 132 always have a clamping force in the direction of the filling hole 121, so that the sealing packing in the filling hole 121 can be clamped by the pressure sleeve 132. Through this arrangement, secondary sealing of the regulating valve of this application can be achieved, further improving the safety of the application, meeting the usage requirements under toxic and hazardous conditions, and possessing practicality.

[0046] In one or more embodiments, the valve disc 6 includes a first sealing portion 61 and a second sealing portion 62 symmetrically arranged on both sides of the second end of the swing arm 5 along the axial direction of the medium channel 101. The first sealing portion 61 and the second sealing portion 62 are connected by an elastic member 14. The flow channel inlet 102 and the flow channel outlet 103 are both recessed into the medium channel 101 to form a boss 15. Along the swing direction of the valve disc 6, at least one guide rib 16 is provided in the medium channel 101 that is flush with the surface of the boss 15.

[0047] See Figures 2 to 6In the initial state, the first sealing part 61 and the second sealing part 62 are always pressed against the protrusions 15 of the flow channel inlet 102 and the flow channel outlet 103 by means of the elastic force of the elastic member 14. This arrangement can further ensure the sealing effect of the valve disc 6 on the flow channel inlet 102 and the flow channel outlet 103. When the rocker arm 3 controls the swing arm 5 to swing, so that the first sealing part 61 and the second sealing part 62 gradually no longer block the flow channel inlet 102 and the flow channel outlet 103, the part of the first sealing part 61 that moves out of the flow channel inlet 102 and the part of the second sealing part 62 that moves out of the flow channel outlet 103 will press against the guide rib 16. The guide rib 16 can limit the first sealing part 61 and the second sealing part 62, ensuring the normal use of the first sealing part 61 and the second sealing part 62.

[0048] In one specific embodiment, the elastic element 14 may be a spring or an elastic airbag.

[0049] In one or more embodiments, the central axis of the first bushing 4 is located relative to the middle of the bellows 7.

[0050] See Figure 3 Half of the bellows 7 is located above the central axis of the first bushing 4, and the other half is located below the central axis of the first bushing 4. With this arrangement, the torsional deformation capacity of the entire bellows 7 can be fully utilized, the length of the bellows 7 can be reduced, and the size of the regulating valve of this application can be reasonably configured.

[0051] In one or more embodiments, the bellows 7 is made of stainless steel, and the wall thickness of the bellows 7 is 0.3-0.9 mm. The stainless steel bellows 7 has the characteristics of high strength, corrosion resistance, and long service life, ensuring the control valve of this application can transport different media and meet the usage requirements under different operating conditions. It is understood that the wall thickness of the bellows 7 can be 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, or 0.9 mm; the wall thickness of the bellows 7 is not specifically limited and can be selected according to actual production needs.

[0052] In other possible implementations, the number of bellows 7 can be set to two, three, four, etc. When there are multiple bellows 7, several bellows 7 can be connected one by one and then welded.

[0053] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They cannot be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.

Claims

1. A bellows seal control valve characterized by, include: The valve body has a through medium channel, the medium channel having a flow inlet and a flow outlet, and the top of the valve body has a receiving port communicating with the medium channel; A valve cover is disposed on the top of the valve body and covers the receiving port; A rocker arm is rotatably mounted on the valve cover by means of a first bushing, the axis of the first bushing being parallel to the axis of the medium channel. A rocker arm has a first end and a second end. The rocker arm passes through the receiving port, so that the first end is fixedly installed on the rocker arm and the second end extends into the medium channel. The second end of the rocker arm is equipped with a valve disc for blocking or opening the flow channel inlet and flow channel outlet. A bellows, the upper end of which is sealed and welded to the bottom surface of the rocker arm, and the lower end of which is sealed and welded to the inner peripheral wall of the receiving port. An actuator, located on the valve cover, is used to laterally push the rocker arm to swing around the axis of the first bushing, thereby driving the rocker arm and the valve disc to move and realize the opening and closing control of the flow channel inlet and outlet.

2. The bellows sealed trim valve of claim 1, wherein: The actuator includes a valve stem that is threaded laterally onto the valve cover. The valve stem has a sleeve end and a handle end. The sleeve end extends into the valve cover and has an opening on the side facing the rocker arm. An extension formed on the upper part of the rocker arm extends into the sleeve end of the valve stem through the opening. When the valve stem moves laterally relative to the valve cover, the extension moves within the sleeve end to push the rocker arm to swing about the axis of the first bushing.

3. The bellows sealed trim valve of claim 2, wherein: The extension is a shaft head rotatably mounted on the side of the rocker arm via a second bushing and a spindle. The spindle is rotatably mounted inside the second bushing, and the shaft head is rotatably mounted on the spindle. The axial direction of the second bushing is parallel to the axial direction of the medium channel.

4. The bellows sealed trim valve of claim 3, wherein: The second bushing is an eccentric bushing, which is rotatable relative to the rocker arm and is fixedly mounted on the rocker arm by means of a locking member.

5. The bellows-sealed regulating valve according to claim 4, characterized in that: The locking component is a circular sawtooth structure that rotates synchronously with the second bushing and a buckle located on the rocker arm that can extend into the tooth groove of the sawtooth structure.

6. The bellows-sealed regulating valve according to claim 3, characterized in that: A plurality of rolling elements are installed between the shaft head and the spindle, evenly arranged around the central axis of the shaft head.

7. The bellows-sealed regulating valve according to claim 1, characterized in that: The valve disc includes a first sealing portion and a second sealing portion symmetrically arranged on both sides of the second end of the rocker arm along the axial direction of the medium channel, and the first sealing portion and the second sealing portion are connected by an elastic element.

8. The bellows-sealed regulating valve according to claim 7, characterized in that: Both the inlet and outlet of the flow channel are recessed into the medium channel to form a boss. Along the swing direction of the valve disc, the medium channel is provided with at least one guide rib that is flush with the surface of the boss.

9. The bellows-sealed regulating valve according to claim 1, characterized in that: The central axis of the first bushing is located at the middle of the bellows.

10. The bellows-sealed regulating valve according to claim 1, characterized in that: The corrugated pipe is made of stainless steel and has a wall thickness of 0.3-0.9 mm.

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