Anti-corrosion structure for armored temperature thermocouple of high and medium pressure cylinder of steam turbine

Abstract

The utility model discloses a steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure, which comprises a heat preservation surface layer of a steam turbine high and medium pressure cylinder, a heat preservation coating material, a thermocouple armoured body and a locking nut, the locking nut is fixed on the heat preservation surface layer, the heat preservation coating material is positioned on the outer side of the heat preservation surface layer, and an anti-corrosion piece is fixed on the outer side of the locking nut. The anti-corrosion piece is connected with the thermocouple armoured body through the screwed joint, and the thermocouple armoured body extends into the high-medium pressure cylinder of the steam turbine through the screwed joint, the anti-corrosion piece, the locking nut and the heat preservation surface layer. According to the anti-corrosion structure for the armored temperature thermocouple of the high and medium pressure cylinder of the steam turbine, through the anti-corrosion device for the armored temperature thermocouple of the high and medium pressure cylinder of the steam turbine and the improvement of the sealing performance, the armored temperature thermocouple is not affected by corrosion measuring points of gas generated by heat preservation materials at high temperature, and meanwhile, safe and stable operation of a unit is guaranteed.

Description

Technical Field

[0001] The utility model relates to a temperature thermocouple installation structure, in particular to an armored temperature thermocouple anti-corrosion installation structure for high and medium pressure cylinders of steam turbines. Background Art

[0002] Thermocouples are commonly used temperature measuring elements in temperature measuring instruments. They directly measure temperature and convert temperature signals into thermoelectric potential signals, which are then converted into the temperature of the measured medium through electrical instruments (secondary instruments). The appearance of various thermocouples is often very different due to needs, but their basic structure is roughly the same. They are usually composed of main parts such as thermode, insulating sleeve protection tube and junction box, and are usually used in conjunction with display instruments, recording instruments and electronic regulators.

[0003] Because the armored temperature thermocouples of the high and medium pressure cylinders of the steam turbine in the thermal power plant must be inserted into the insulation surface layer before passing through the insulation surface layer before being inserted into the high-pressure cylinder temperature sampling lock nut to enter the high-pressure cylinder, the stainless steel armored thermocouple will be corroded at the junction of the insulation layer and the insulation surface layer. Due to the high temperature of the insulation material, the hot gas generated by the temperature thermocouple will corrode the armor layer and the measuring point will be damaged. The temperature thermocouple cannot measure the temperature of the high-pressure cylinder normally, causing the operating personnel to observe the internal temperature of the high-pressure cylinder in a distorted manner, which may lead to misjudgment and misoperation, resulting in serious consequences. Utility Model Content

[0004] The utility model aims to provide a steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure to solve the problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] The armored temperature thermocouple anti-corrosion structure of the high and medium pressure cylinders of the turbine includes an insulation surface layer, an insulation wiper surface, a thermocouple body and a locking nut of the high and medium pressure cylinders of the turbine. The locking nut is fixed on the insulation surface layer, and the insulation wiper surface is located on the outside of the insulation surface layer. An anti-corrosion part is fixed on the outside of the locking nut. The anti-corrosion part is connected to the thermocouple body through a threaded joint. The thermocouple body extends into the high and medium pressure cylinders of the turbine through the threaded joint, the anti-corrosion part, the locking nut and the insulation surface layer.

[0007] As a further solution of the utility model: an anti-corrosion seat is arranged at the bottom of the anti-corrosion part, the anti-corrosion seat is located on the outside of the locking nut, the anti-corrosion seat and the anti-corrosion part are welded to the locking nut, and the top of the anti-corrosion part extends to the outside of the thermal insulation fabric.

[0008] As a further solution of the utility model: a hexagonal nut is arranged on the outside of the threaded joint, and the top of the hexagonal nut is a protective sleeve. After the anti-corrosion part and the threaded joint are locked, there is a gap between the bottom of the hexagonal nut and the top of the anti-corrosion part.

[0009] As a further solution of the utility model: a dust cover located outside the anti-corrosion part is provided at the bottom of the hexagonal nut.

[0010] As a further solution of the utility model: a labyrinth sealing circuit is arranged on the bottom surface of the threaded joint, and a labyrinth sealing groove matching the labyrinth sealing circuit is arranged in the anti-corrosion component. The labyrinth sealing circuit and the labyrinth sealing groove are interlocked to form a sealing structure after the threaded joint and the anti-corrosion component are locked.

[0011] As a further solution of the utility model: the length of the threaded joint is greater than the length of the anti-corrosion part, and the labyrinth sealing circuit and the labyrinth sealing groove on the bottom surface of the threaded joint are completely embedded.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] The steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure protects the steam turbine high and medium pressure cylinder armored temperature thermocouples and improves the sealing performance, so that the measuring points are not damaged by the corrosion of the gas generated by the high temperature of the insulation material, and also provides a guarantee for the safe and stable operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of a steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure;

[0015] Figure 2 This is a structural decomposition diagram of the anti-corrosion parts in the armored temperature thermocouple anti-corrosion structure of a steam turbine high and medium pressure cylinder;

[0016] Figure 3 It is a structural schematic diagram of a labyrinth seal groove in a steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure;

[0017] Figure 4 The schematic diagram of the structure of the labyrinth sealing circuit in the armored temperature thermocouple corrosion protection structure of a steam turbine high and medium pressure cylinder.

[0018] In the figure: 1. Insulation surface layer; 2. Insulation wiper fabric; 3. Thermocouple body; 4. Locking nut; 5. Anti-corrosion seat; 6. Anti-corrosion part; 7. Protective sleeve; 8. Hexagonal nut; 9. Threaded joint; 10. Dust cover; 11. Labyrinth seal groove; 12. Labyrinth seal loop. DETAILED DESCRIPTION

[0019] See also Figures 1 to 4In the embodiment of the utility model, the steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure includes a thermal insulation surface layer 1, a thermal insulation wipe surface 2, a thermocouple body 3 and a locking nut 4 of the steam turbine high and medium pressure cylinder, the locking nut 4 is fixed on the thermal insulation surface layer 1, the thermal insulation wipe surface 2 is located on the outside of the thermal insulation surface layer 1, and an anti-corrosion part 6 is fixed on the outside of the locking nut 4, the anti-corrosion part 6 is connected to the thermocouple body 3 through a threaded joint 9, the thermocouple body 3 extends into the steam turbine high and medium pressure cylinder through the threaded joint 9, the anti-corrosion part 6, the locking nut 4 and the thermal insulation surface layer 1, and the anti-corrosion part 6 of 3mm thick ø20mm is welded on the locking nut 4 at the measuring point, the anti-corrosion part 6 is tubular, and the length of the anti-corrosion part 6 extends to the outside of the thermal insulation wipe surface 2, and the anti-corrosion The outer side of the component 6 is coated with anti-corrosion material, and the anti-corrosion component 6 is threadedly connected to the threaded joint 9, and the interiors are interconnected after the connection. The thermocouple body 3 extends through its interior to the interior of the high and medium pressure cylinders of the steam turbine. The thermocouple body 3 is protected by the anti-corrosion component 6 to prevent the thermocouple from corroding at the junction of the insulation surface layer 1 and the insulation wiped surface layer 2. A comparison of the 50 temperature measuring points of the two units before and after the transformation found that the temperature measuring points were corroded in less than a year before the transformation, but now they can be used for more than 5 years without being corroded. After the transformation, the temperature thermocouple of the thermocouple body 3 is no longer affected by the corrosive gas, and the temperature display is no longer distorted, ensuring the safe operation of the unit. It can be seen that after the transformation, the risk of misoperation for the enterprise is reduced, etc., and the enterprise's efforts to create profits are contributed to.

[0020] In a preferred embodiment, an anti-corrosion seat 5 is provided at the bottom of the anti-corrosion part 6, and the anti-corrosion seat 5 is located on the outside of the locking nut 4. The anti-corrosion seat 5 and the anti-corrosion part 6 are both welded to the locking nut 4. The top of the anti-corrosion part 6 extends to the outside of the thermal insulation surface layer 2. The original locking nut 4 is connected to the threaded joint 9 set on the thermocouple body 3. Since the anti-corrosion part 6 is added to the locking nut 4, the thermocouple body 3 needs to be installed on the anti-corrosion part 6. Therefore, extremely high connection stability and sealing are required between the anti-corrosion part 6 and the locking nut 4. The anti-corrosion part 6 and the anti-corrosion seat 5 are integrally formed. By welding the anti-corrosion seat 5 to the thermal insulation surface layer 1 or the locking nut 4, the welding effect can be effectively improved and the stability and sealing can be maintained.

[0021] In a preferred embodiment, a hexagonal nut 8 is provided on the outside of the threaded joint 9, and the top of the hexagonal nut 8 is a protective sleeve 7. After the anti-corrosion component 6 and the threaded joint 9 are locked, there is a gap between the bottom of the hexagonal nut 8 and the top of the anti-corrosion component 6. The hexagonal nut 8 is convenient for the staff to twist and lock it with the help of tools. A dust cover 10 is provided on the bottom of the hexagonal nut 8 and is located on the outside of the anti-corrosion component 6. The dust cover 10 can not only prevent external corrosive liquids or dust from contacting the threaded structure of the threaded joint 9 and the anti-corrosion component 6, but also change the direction of steam during disassembly or leakage to avoid direct steam spray and burns.

[0022] In a preferred embodiment, a labyrinth sealing circuit 12 is provided on the bottom surface of the threaded joint 9, and a labyrinth sealing groove 11 matching the labyrinth sealing circuit 12 is provided in the anti-corrosion component 6. The labyrinth sealing circuit 12 and the labyrinth sealing groove 11 are interlocked to form a sealing structure after the threaded joint 9 and the anti-corrosion component 6 are locked. A labyrinth seal refers to a seal with many tortuous chambers between rotating parts and fixed parts to reduce leakage. It is an ideal labyrinth flow channel model, in which a number of annular sealing teeth arranged in sequence are provided around the rotating shaft, and a series of intercepting gaps and expansion cavities are formed between the teeth. When the sealed medium passes through the gap of the tortuous labyrinth, a throttling effect is generated to achieve the purpose of blocking leakage. Arranging a labyrinth seal on the contact surface of the threaded joint 9 and the anti-corrosion component 6 can effectively improve the sealing effect and achieve a leak-proof effect.

[0023] In a preferred embodiment, the length of the threaded joint 9 is greater than the length of the anti-corrosion part 6, and the labyrinth sealing circle 12 and the labyrinth sealing groove 11 on the bottom of the threaded joint 9 are fully engaged. During the locking process, the contact between the anti-corrosion part 6 and the hexagonal nut 8 will affect the locking of the anti-corrosion part 6 and the threaded joint 9. In order to ensure that the labyrinth sealing circle 12 and the labyrinth sealing groove 11 are fully engaged and achieve a sealing effect, the length of the threaded joint 9 needs to be one millimeter greater than the length of the anti-corrosion part 6.

[0024] It should be noted that the above embodiments all belong to the same utility model concept, and the description of each embodiment has its own focus. For matters that are not described in detail in some embodiments, reference can be made to the description in other embodiments.

[0025] The above-mentioned embodiments only express the implementation methods of the utility model, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, and these all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure, comprising a steam turbine high and medium pressure cylinder insulation surface layer (1), an insulation wiper material (2), a thermocouple body (3) and a locking nut (4), wherein the locking nut (4) is fixed on the insulation surface layer (1), and the insulation wiper material (2) is located on the outside of the insulation surface layer (1), characterized in that: An anti-corrosion component (6) is fixed to the outer side of the locking nut (4); the anti-corrosion component (6) is connected to the thermocouple body (3) via a threaded joint (9); and the thermocouple body (3) extends into the high and medium pressure cylinders of the steam turbine via the threaded joint (9), the anti-corrosion component (6), the locking nut (4) and the thermal insulation surface layer (1).

2. The steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure according to claim 1 is characterized in that: An anti-corrosion seat (5) is provided at the bottom of the anti-corrosion member (6), the anti-corrosion seat (5) is located outside the locking nut (4), the anti-corrosion seat (5) and the anti-corrosion member (6) are both welded to the locking nut (4), and the top of the anti-corrosion member (6) extends to the outside of the thermal insulation fabric (2).

3. The steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure according to claim 1 is characterized in that: A hexagonal nut (8) is arranged on the outside of the threaded joint (9), and the top of the hexagonal nut (8) is a protective sleeve (7). After the anti-corrosion component (6) and the threaded joint (9) are locked, a gap exists between the bottom of the hexagonal nut (8) and the top of the anti-corrosion component (6).

4. The steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure according to claim 3 is characterized in that: The bottom of the hexagonal nut (8) is provided with a dust cover (10) located outside the anti-corrosion component (6).

5. The steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure according to any one of claims 1 to 4, characterized in that: A labyrinth sealing loop (12) is provided on the bottom surface of the threaded joint (9), and a labyrinth sealing groove (11) matching the labyrinth sealing loop (12) is provided in the anti-corrosion component (6). After the threaded joint (9) and the anti-corrosion component (6) are locked, the labyrinth sealing loop (12) and the labyrinth sealing groove (11) are interlocked to form a sealing structure.

6. The steam turbine high and medium pressure cylinder armored temperature thermocouple anti-corrosion structure according to claim 5 is characterized in that: The length of the threaded joint (9) is greater than the length of the anti-corrosion component (6), and the labyrinth sealing loop (12) on the bottom surface of the threaded joint (9) and the labyrinth sealing groove (11) are completely fitted together.

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