Shaft seal electric heater capable of automatically regulating temperature

Abstract

The utility model discloses a shaft seal electric heater capable of adjusting temperature automatically, which relates to the technical field of shaft seal electric heaters, and is characterized by comprising a heater main body and a steam supply pipe arranged on the heater main body, and further comprising an adjusting mechanism arranged on the steam supply pipe and communicated with the steam supply pipe, the steam pipe is used for automatically adjusting steam flow conveyed by the steam pipe; the adjusting mechanism comprises an overflowing box, a connecting pipe head arranged on the overflowing box, a temperature measuring assembly arranged in the overflowing box and used for measuring the steam temperature and a flow control assembly controlled by the temperature measuring assembly and used for adjusting the steam flow. The device can regulate and control the flow of the steam introduced from the shaft seal side of the high-pressure cylinder, and can automatically regulate the flow of the steam fed into the shaft seal side of the low-pressure cylinder when the temperature is too high, so that the temperature of the steam is reduced, and an operation structure in the low-pressure cylinder is protected.

Description

Technical Field

[0001] The utility model relates to the technical field of shaft seal electric heaters, in particular to a shaft seal electric heater capable of automatically regulating temperature. Background Art

[0002] The shaft seal electric heater is a device used to supply steam to the shaft seal side of the steam turbine in a power plant. During the operation of the steam turbine, a certain interval needs to be maintained between the rotor and the cylinder to prevent friction between the two. This interval will cause some steam leakage, so a shaft seal structure is set in the interval. This shaft seal structure will still have some steam leakage after sealing. At this time, a shaft seal electric heater is needed, which can extract the leaked steam and reflux it for utilization. In most cases, the steam on the shaft seal side of the high-pressure cylinder is extracted to the shaft seal side of the low-pressure cylinder, so that it can be recovered to seal the shaft seal side of the low-pressure cylinder. However, the temperature of the steam needs to be kept consistent to form a stable sealing environment. The steam leaking on the shaft seal side of the high-pressure cylinder is often at a higher temperature than that on the shaft seal side of the low-pressure cylinder. In this case, the temperature difference will increase, and the bearing and return oil pipeline will be damaged by thermal stress.

[0003] In view of this, a design or technical improvement is now proposed to solve the above problems.

[0004] The above contents are only used to assist in understanding the technical solution of the present utility model, and do not constitute an admission that the above contents are the closest prior art. Utility Model Content

[0005] The utility model aims to solve the above-mentioned shortcomings and provide a shaft seal electric heater which can automatically adjust the temperature.

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A shaft seal electric heater capable of self-regulating temperature, comprising a heater body and a steam delivery pipe arranged on the heater body, and further comprising:

[0008] A regulating mechanism is arranged on the steam delivery pipe and is connected to the steam delivery pipe, and is used for automatically regulating the steam flow delivered by the steam delivery pipe;

[0009] The regulating mechanism comprises a flow box, a connecting pipe head arranged on the flow box, a temperature measuring component arranged in the flow box and used to measure the steam temperature, and a flow control component controlled by the temperature measuring component and used to adjust the steam flow.

[0010] Furthermore, the temperature measuring assembly includes an expansion sleeve and connecting plates arranged on both sides of the expansion sleeve, the expansion sleeve is suspended inside the heater body through the connecting plates, and the expansion sleeve is made of metal with thermal expansion properties.

[0011] Furthermore, the flow control component includes a flow pipe which is arranged in the heater body and whose two ends are respectively connected to the steam supply pipe and the connecting pipe head, and a valve component which is arranged on the flow pipe.

[0012] Furthermore, the valve assembly includes a regulating valve plate with bearings at both ends connected to the inner wall of the flow tube, and a movable slide rod with one end hinged to the regulating valve plate and the other end fixed to the inner wall of the expansion sleeve, wherein the movable slide rod is movably connected to the wall of the flow tube.

[0013] Furthermore, a sealed thermal sensing chamber is formed between the expansion sleeve and the flow box. One side of the thermal sensing chamber is connected to the steam supply pipe through a shunt pipe, and the other side is connected to the connecting pipe head through a return pipe.

[0014] Compared with the prior art, the beneficial effect of this solution is that the device can regulate the flow of steam introduced from the high-pressure cylinder shaft seal side, and when the temperature is too high, it can automatically adjust the steam flow sent to the low-pressure cylinder shaft seal side, thereby reducing the steam temperature and protecting the operating structure in the low-pressure cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0016] Figure 1 It is a front three-dimensional schematic diagram of the utility model;

[0017] Figure 2 It is a three-dimensional schematic diagram of the adjustment mechanism in the utility model;

[0018] Figure 3 It is a cross-sectional stereoscopic schematic diagram of the adjustment mechanism in the utility model;

[0019] Figure 4 It is a schematic diagram of the coordination between the temperature measuring assembly frame and the flow control assembly in the present utility model.

[0020] In the figure: 1. Heater body; 11. Steam supply pipe; 2. Flow box; 21. Connecting pipe head; 22. Expansion sleeve; 23. Connecting plate; 24. Thermal sensing chamber; 25. Diverter pipe; 26. Return pipe; 3. Flow pipe; 31. Regulating valve plate; 32. Movable sliding rod. DETAILED DESCRIPTION

[0021] The following will be combined with the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. In the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0022] like Figure 1-4 The shaft seal electric heater with self-regulating temperature shown in the figure comprises a heater body 1 and a steam supply pipe 11 arranged on the heater body 1, and also comprises an adjusting mechanism, which is arranged on the steam supply pipe 11 and communicated with the steam supply pipe 11, and is used to automatically adjust the steam flow rate delivered by the steam supply pipe 11; the adjusting mechanism comprises a flow box 2, a connecting pipe head 21 arranged on the flow box 2, a temperature measuring component arranged in the flow box 2 and used to measure the steam temperature, and a flow control component controlled by the temperature measuring component to adjust the steam flow rate, the connecting pipe head 21 is connected to the steam supply pipe on the shaft seal side of the low-pressure cylinder, the heater body 1 sucks the leaked steam from the shaft seal side of the high-pressure cylinder and processes it, and then transports it to the shaft seal side of the low-pressure cylinder through the steam supply pipe 11, so that it is refluxed for use, because the steam temperature in the high-pressure cylinder and the low-pressure cylinder is too different, and then the adjusting mechanism is introduced, and the steam temperature is measured by using the temperature measuring component arranged inside it, when the measured temperature is too high, the steam flow rate delivered can be controlled by the flow control component, and then the steam temperature is changed accordingly to match the temperature of the shaft seal side of the low-pressure cylinder.

[0023] In one embodiment, the temperature measuring component includes an expansion sleeve 22 and a connecting plate 23 arranged on both sides of the expansion sleeve 22. The expansion sleeve 22 is suspended inside the heater body 1 through the connecting plate 23, and the expansion sleeve 22 is made of a metal with thermal expansion properties. The flow control component includes a flow pipe 3 arranged in the heater body 1 and connected to the steam supply pipe 11 and the connecting pipe head 21 at both ends, and a valve assembly arranged on the flow pipe 3. The expansion sleeve 22 utilizes its own thermal expansion properties to achieve thermal deformation, and then controls the valve assembly through deformation, thereby achieving the effect of automatically adjusting the steam flow.

[0024] In one embodiment, the valve assembly includes a regulating valve plate 31 with bearings at both ends connected to the inner wall of the flow tube 3, and a movable slide rod 32 with one end hinged to the regulating valve plate 31 and the other end fixed to the inner wall of the expansion sleeve 22. The movable slide rod 32 is movably connected to the wall of the flow tube 3. When the expansion sleeve 22 is affected by high-temperature steam, it will expand itself, thereby driving the movable slide rod 32 to extend into the interior of the flow tube 3. The extension of the movable slide rod 32 drives the regulating valve plate 31 to rotate, thereby changing the flow area of ​​the flow tube 3, thereby reducing the steam flow rate. When the steam flow rate is reduced, its temperature will also decrease accordingly to achieve the purpose of temperature control. The thermal expansion effect of the expansion sleeve 22 is designed and adjusted according to the actual temperature protection range of the low-pressure cylinder shaft seal side, thereby meeting the steam supply temperature requirement on the low-pressure cylinder shaft seal side.

[0025] In one embodiment, a sealed thermal sensing chamber 24 is formed between the expansion sleeve 22 and the flow box 2. One side of the thermal sensing chamber 24 is connected to the steam supply pipe 11 through a bypass pipe 25, and the other side is connected to the connecting pipe head 21 through a return pipe 26. In order to ensure the temperature sensitivity of the expansion sleeve 22 and keep it at a high temperature so that it can make deformation feedback faster, a small part of the steam in the steam supply pipe 11 is diverted through the bypass pipe 25 and introduced into the thermal sensing chamber 24, so that the steam directly contacts the expansion sleeve 22 to complete efficient heat conduction. At the same time, the return pipe 26 diverts the steam inside the thermal sensing chamber 24 to the connecting pipe head 21 for transportation, so that it does not affect the stability of steam transportation. In addition, the flow rate of this part of the steam is small, and it will not cause a large temperature impact on the steam transported from the connecting pipe head 21.

[0026] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

Claims

1. A self-regulating temperature-controlled shaft seal electric heater, comprising a heater body (1) and a steam delivery pipe (11) arranged on the heater body (1), characterized in that: include: A regulating mechanism, which is arranged on the steam delivery pipe (11) and is in communication with the steam delivery pipe (11), and is used for automatically regulating the flow rate of steam delivered by the steam delivery pipe (11); The regulating mechanism comprises a flow box (2), a connecting pipe head (21) arranged on the flow box (2), a temperature measuring component arranged in the flow box (2) and used to measure the steam temperature, and a flow control component controlled by the temperature measuring component and used to regulate the steam flow rate.

2. The self-adjustable temperature-controlled shaft seal electric heater according to claim 1, characterized in that: The temperature measuring component comprises an expansion sleeve (22) and connecting plates (23) arranged on both sides of the expansion sleeve (22), the expansion sleeve (22) is suspended inside the heater body (1) through the connecting plates (23), and the expansion sleeve (22) is made of metal with thermal expansion properties.

3. The self-temperature-adjustable shaft seal electric heater according to claim 2, characterized in that: The flow control component comprises a flow pipe (3) arranged in the heater body (1) and having two ends respectively connected to the steam supply pipe (11) and the connecting pipe head (21), and a valve component arranged on the flow pipe (3).

4. The self-adjustable temperature-controlled shaft seal electric heater according to claim 3, characterized in that: The valve assembly comprises a regulating valve plate (31) whose two ends are connected to the inner wall of the flow tube (3) by bearings, and a movable sliding rod (32) whose one end is hinged to the regulating valve plate (31) and the other end is fixed to the inner wall of the expansion sleeve (22); the movable sliding rod (32) is movably connected to the wall of the flow tube (3).

5. The self-adjustable temperature-controlled shaft seal electric heater according to claim 2, characterized in that: A sealed thermal sensing chamber (24) is also formed between the expansion sleeve (22) and the flow box (2); one side of the thermal sensing chamber (24) is connected to the steam supply pipe (11) through a shunt pipe (25), and the other side is connected to the connecting pipe head (21) through a return pipe (26).

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