High-pressure main steam valve steel casting of ultra-supercritical double-cylinder single-exhaust condensing unit

Abstract

The ultra-supercritical double-cylinder single-exhaust condensing unit high-pressure main steam valve steel casting comprises a valve body casting, a valve cavity is formed in the valve body casting, a valve rod mounting through hole is formed in the right end of the valve cavity, an annular air leakage groove is formed in the position of an inner port of the valve rod mounting through hole, and an air leakage channel is partially formed in the annular air leakage groove; a packing is arranged in the valve rod mounting through hole, a positioning gland is integrally arranged at the outer end of the packing, and the positioning gland is detachably connected with the right end face of the valve body casting. A plurality of bolt through holes are formed in the side face of the valve rod installation through hole, a plurality of threaded blind holes are formed in the outer surface of the packing, a limiting bolt is arranged in each bolt through hole, a positioning sleeve is fixedly arranged at the inner end of the packing, and a plurality of valve rod positioning pieces are fixedly arranged on the inner surface of the positioning sleeve. According to the technical scheme, the structural design is reasonable, the packing is not prone to damage, the packing is easy to replace, maintenance and repair operation is simple, and practicability is good.

Description

Technical Field

[0001] The utility model relates to the technical field of condensing machines, in particular to a high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing machine unit. Background Art

[0002] The valve stem of the existing high-pressure main steam valve of the ultra-supercritical twin-cylinder single-exhaust condensing unit is a moving part, so it needs to be sealed with the valve body. When the condensing unit is started or stopped or started in a cold state, the high-pressure main steam valve is not fully opened for a long time. At this time, the high-pressure impact is likely to cause the packing to be damaged. After the packing is damaged, a large amount of steam will leak from the mounting hole of the valve stem. Moreover, the packing of the high-pressure main steam valve of the existing ultra-supercritical twin-cylinder single-exhaust condensing unit is integrally cast with the valve body, the structural design is unreasonable, the packing is difficult to replace, resulting in difficulty in maintenance and repair, and poor practicality. Utility Model Content

[0003] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a high-pressure main steam valve casting for an ultra-supercritical twin-cylinder single-exhaust condensing unit which has a reasonable structural design, a packing that is not easily damaged, an easy packing replacement, simple maintenance and repair operations, and good practicality.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit, comprising a valve body casting, a valve cavity is arranged in the valve body casting, a steam inlet through hole is arranged at the lower end of the valve cavity, a steam outlet through hole is arranged at the left end of the valve cavity, a valve stem mounting through hole is arranged at the right end of the valve cavity, an annular air leakage groove is arranged at the inner port position of the valve stem mounting through hole, and an air leakage channel is arranged locally in the annular air leakage groove;

[0005] A packing is arranged in the valve stem mounting through hole, and a positioning gland is integrally arranged at the outer end of the packing, and the positioning gland is detachably connected to the right end face of the valve body casting; a plurality of bolt through holes are arranged on the side of the valve stem mounting through hole, and a plurality of threaded blind holes are arranged on the outer surface of the packing, and a limiting bolt is arranged in each bolt through hole, and the inner end of the limiting bolt passes through the bolt through hole and is threadedly connected with the aligned threaded blind hole;

[0006] A positioning sleeve is fixedly arranged at the inner end of the packing, and a plurality of valve stem positioning members are fixedly arranged on the inner surface of the positioning sleeve.

[0007] The utility model is further configured as follows: the valve stem positioning member is in a ring-shaped structure, and the valve stem positioning member is made of a high-temperature resistant elastic material.

[0008] The utility model is further configured as follows: the positioning sleeve and the packing are integrally arranged, and the positioning sleeve and the packing are both made of stainless steel or hard alloy, and the inner end of the positioning sleeve is arranged close to the groove opening of the annular air relief groove.

[0009] The utility model is further configured as follows: a first elastic gasket is arranged between the positioning gland and the right end surface of the valve body casting, and a second elastic gasket is arranged between the limiting bolt and the outer surface of the valve body casting.

[0010] The utility model is further configured as follows: the valve stem positioning member is a polytetrafluoroethylene gasket or a carbon fiber gasket or a high temperature resistant silicone gasket.

[0011] The utility model is further configured as follows: the valve body casting is provided with a one-way valve installation groove at the outer port position of the air leakage channel.

[0012] The beneficial effects of the utility model are as follows: compared with the prior art, the utility model has a reasonable structural design, a valve stem through hole is arranged in the middle of the packing, the valve stem is installed in the valve stem through hole, and the one-way valve is installed in the one-way valve installation groove; under normal working conditions, the air leakage channel is closed, and the packing realizes the sealing of the outer periphery of the valve stem; when the ultra-supercritical double-cylinder single-exhaust condensing unit is started or stopped or started in a cold temperature state, the pressure in the valve cavity is relatively large at this time, and a gas release effect can be formed before the packing through the air leakage channel, thereby preventing high-temperature steam from leaking from the packing.

[0013] A positioning sleeve is provided at the inner end of the packing, and the valve stem positioning piece on the inner surface of the positioning sleeve plays a positioning and buffering role for the valve stem, so that the valve stem works reliably and shakes less, thereby protecting the packing, avoiding or reducing damage to the packing, and making the packing less prone to damage;

[0014] The outer end of the packing is connected by a positioning bolt, and the inner end of the packing is limited by a limiting bolt. It is reliably fixed and easy to assemble and disassemble, making the packing easy to replace, simple to maintain and repair, and has good practicality.

[0015] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of an embodiment of the utility model;

[0017] Figure 2 This is a partial schematic diagram of an embodiment of the utility model. Figure 1 ;

[0018] Figure 3 This is a partial schematic diagram of an embodiment of the utility model. Figure 2 . DETAILED DESCRIPTION

[0019] In the description of this embodiment, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "back", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore, cannot be understood as a limitation on the utility model. In addition, if the terms "first", "second", and "third" appear, they are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0020] See also Figures 1 to 3 The utility model discloses a high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit, comprising a valve body casting 1, wherein a valve cavity 11 is arranged in the valve body casting 1, wherein a steam inlet through hole 12 is arranged at the lower end of the valve cavity 11, a steam outlet through hole 13 is arranged at the left end of the valve cavity 11, and a valve stem mounting through hole 14 is arranged at the right end of the valve cavity 11, wherein an annular air leakage groove 141 is arranged at the inner port position of the valve stem mounting through hole 14, and a partial air leakage channel 15 is arranged in the annular air leakage groove 141;

[0021] The valve stem mounting through hole 14 is provided with a packing 2, and a positioning gland 21 is integrally provided at the outer end of the packing 2, and the positioning gland 21 is detachably connected to the right end surface of the valve body casting 1; a plurality of bolt through holes 16 are provided on the side of the valve stem mounting through hole 14, and a plurality of threaded blind holes 22 are provided on the outer surface of the packing 2, and a limiting bolt 3 is provided in each bolt through hole 16, and the inner end of the limiting bolt 3 passes through the bolt through hole 16 and is threadedly connected with the aligned threaded blind hole 22;

[0022] A positioning sleeve 23 is fixedly disposed at the inner end of the packing 2 , and a plurality of valve stem positioning members 24 are fixedly disposed on the inner surface of the positioning sleeve 23 .

[0023] Preferably, 2-4 positioning bolts are arranged between the positioning cover 21 and the right end face of the valve body casting 1, and the positioning cover 21 is locked on the right end face of the valve body casting 1 by the positioning bolts; the number of the bolt through holes 16 on the side of the valve stem mounting through hole 14 is set to 1-6, the number of the threaded blind holes 22 on the outer surface of the packing 2 is the same as the number of the bolt through holes 16, and the positions of the threaded blind holes 22 match the positions of the bolt through holes 16.

[0024] In order to make the structural design of the utility model more reasonable, as a preferred embodiment, the valve stem positioning member 24 of the present embodiment is in a ring-shaped structure, and the valve stem positioning member 24 is made of a high temperature resistant elastic material.

[0025] The positioning sleeve 23 and the packing 2 are integrally arranged, and both the positioning sleeve 23 and the packing 2 are made of stainless steel or hard alloy. The inner end of the positioning sleeve 23 is arranged close to the groove opening of the annular air release groove 141 .

[0026] A first elastic gasket 4 is arranged between the positioning gland 21 and the right end surface of the valve body casting 1 , and a second elastic gasket is arranged between the limiting bolt 3 and the outer surface of the valve body casting 1 .

[0027] The valve stem locator 24 is a polytetrafluoroethylene gasket, a carbon fiber gasket, or a high temperature resistant silicone gasket. Preferably, the number of the valve stem locators 24 is 1-3, and the valve stem locators 24 are all fixed to the inner surface of the locating sleeve 23 by glue or screw connection.

[0028] The valve body casting 1 is provided with a one-way valve installation groove 17 at the outer end position of the air leakage channel 15 .

[0029] The valve body casting 1 is cast from high temperature resistant cast steel material ZG35Cr24Ni7SiN or from stainless steel material.

[0030] In actual application, a valve stem through hole is provided in the middle of the packing 2, a valve stem is installed in the valve stem through hole, and a one-way valve is installed in the one-way valve installation groove 17; under normal working conditions, the leakage channel 15 is closed, and the packing 2 realizes the sealing of the outer periphery of the valve stem. When the ultra-supercritical twin-cylinder single-exhaust condensing unit is started or stopped or started in a cold temperature state, the pressure in the valve cavity 11 is relatively high at this time, and a gas release effect can be formed before the packing 2 through the leakage channel 15, thereby preventing high-temperature steam from leaking from the packing 15.

[0031] The utility model has a reasonable structure. A positioning sleeve 23 is provided at the inner end of the packing 2. The valve stem positioning member 24 on the inner surface of the positioning sleeve 23 plays a positioning and buffering role for the valve stem, so that the valve stem works reliably and shakes less, thereby achieving a protective effect on the packing 2, avoiding or reducing damage to the packing 2, and making the packing not easily damaged;

[0032] The outer end of the packing 2 is connected by a positioning bolt, and the inner end of the packing 2 is limited by a limiting bolt. The packing is reliably fixed and easy to assemble and disassemble, making the packing easy to replace, simple to maintain and repair, and having good practicality.

[0033] The specific description of the present invention in the above embodiments is only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Technical engineers in this field may make some non-essential improvements and adjustments to the present invention based on the contents of the above-mentioned utility model, which fall within the scope of protection of the present invention.

Claims

1. A steel casting for a high-pressure main steam valve of an ultra-supercritical double-cylinder single-exhaust condensing unit, comprising a valve body casting (1), wherein a valve cavity (11) is arranged in the valve body casting (1), a steam inlet through hole (12) is arranged at the lower end of the valve cavity (11), a steam outlet through hole (13) is arranged at the left end of the valve cavity (11), and a valve stem mounting through hole (14) is arranged at the right end of the valve cavity (11), characterized in that: An annular air leakage groove (141) is provided at the inner end position of the valve stem mounting through hole (14), and an air leakage channel (15) is partially provided in the annular air leakage groove (141); A packing (2) is arranged in the valve stem mounting through hole (14), and a positioning gland (21) is integrally arranged at the outer end of the packing (2), and the positioning gland (21) is detachably connected to the right end surface of the valve body casting (1); a plurality of bolt through holes (16) are arranged on the side of the valve stem mounting through hole (14), and a plurality of threaded blind holes (22) are arranged on the outer surface of the packing (2), and a limiting bolt (3) is arranged in each bolt through hole (16), and the inner end of the limiting bolt (3) passes through the bolt through hole (16) and is threadedly connected to the aligned threaded blind hole (22); A positioning sleeve (23) is fixedly arranged at the inner end of the packing (2), and a plurality of valve stem positioning members (24) are fixedly arranged on the inner surface of the positioning sleeve (23).

2. The high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit according to claim 1 is characterized in that: The valve stem positioning member (24) is in a ring-shaped structure, and the valve stem positioning member (24) is made of a high-temperature resistant elastic material.

3. The high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit according to claim 2 is characterized in that: The positioning sleeve (23) and the packing (2) are integrally arranged, and both the positioning sleeve (23) and the packing (2) are made of stainless steel or hard alloy. The inner end of the positioning sleeve (23) is arranged close to the groove opening of the annular air release groove (141).

4. The high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit according to claim 1 or 3, characterized in that: A first elastic gasket (4) is arranged between the positioning gland (21) and the right end surface of the valve body casting (1), and a second elastic gasket is arranged between the limiting bolt (3) and the outer surface of the valve body casting (1).

5. The high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit according to claim 1 or 3, characterized in that: The valve stem positioning member (24) is a polytetrafluoroethylene gasket, a carbon fiber gasket, or a high-temperature resistant silicone gasket.

6. The high-pressure main steam valve steel casting of an ultra-supercritical double-cylinder single-exhaust condensing unit according to claim 1 or 3, characterized in that: The valve body casting (1) is provided with a one-way valve installation groove (17) at the outer port position of the air leakage channel (15).

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