Steam turbine oil filtering pipeline hardening and oil level linkage protection device

Abstract

The utility model discloses a steam turbine oil filter pipeline hardening and oil level linkage protection device, and belongs to the technical field of steam turbine oil filter systems. According to the utility model, an oil filtering pipeline is transformed into a structure of a galvanized steel pipe and a high-temperature-resistant and high-pressure-resistant metal hose loose joint, a first manual valve and a first electromagnetic valve are connected in series on an oil filtering and supplying pipeline, a pressure difference transmitter is connected in parallel, and an integrated oil supplementing pipeline and a bypass emergency switching pipeline are designed; the DCS control system is connected into the liquid level sensor, linkage control over oil level and pressure difference signals is achieved through the wireless two-way controller, an oil way can be rapidly cut off when the oil level is lower than a threshold value, early warning adjustment can be conducted when the pressure is abnormal, the stability of the oil level is guaranteed through the oil supplementing system, and the fault emergency capacity is improved through bypass switching. Therefore, the utility model thoroughly solves the problems that the hose of the existing oil filtering system is easy to age and leak oil, the automation control is insufficient and the like, and further improves the reliability, the automation level and the safety production efficiency of the oil filtering system.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of oil filter system of steam turbine, specifically relates to a kind of steam turbine oil filter pipeline hardening and oil level linkage protection device. BACKGROUND

[0002] In the steam turbine generator set of coal-fired power plant, oil filter system is mainly through circulation filtration to remove metal debris, moisture and oxidized impurities in oil, to ensure the stability of steam turbine bearing lubrication, regulating system hydraulic control. Therefore, the operation of filter system is directly related to the energy efficiency level and safety in production of unit, which requires higher requirements for the design and automatic control of filter pipeline.

[0003] At present, the main equipment purchased from original factory adopts hose as oil pipeline from steam turbine body to oil filter, and the hose is mainly made of rubber or plastic material, which is easy to be aged and failed due to oil erosion, temperature change and other factors after long-term operation, resulting in pipeline damage and even interface falling accident. In addition, the control logic and actuator of existing oil filter system have the problem of insufficient automation. The pipeline connected between oil filter and steam turbine body is generally controlled by manual valve, and lacks electric actuator and real-time monitoring linkage mechanism. When oil leakage accident occurs, the operator needs to manually close the valve on site, and cannot realize rapid intervention in the early stage of oil leakage. At the same time, the existing system does not integrate oil level dynamic monitoring and automatic cut-off function, and when the oil tank oil level is lower than the safety threshold to trigger alarm, the oil filter still continues to run, resulting in further oil level drop and further secondary failure such as dry running damage of oil filter or steam turbine lubrication system pressure loss.

[0004] Therefore, how to introduce oil level linkage protection mechanism in the process of simple pipeline replacement and modification of original oil filter system to improve automation level and safety becomes the key problem to be solved in this technical improvement project. CONTENT OF UTILITY MODEL

[0005] In view of the problems existing in the existing oil filter system in the background art, the utility model provides a kind of steam turbine oil filter pipeline hardening and oil level linkage protection device.

[0006] In order to achieve the above object, the utility model discloses the following technical scheme: a steam turbine oil filter oil supply pipeline hardening and oil level linkage protection device, including the oil tank and oil filter, install liquid level sensor on the oil tank, its signal output end is connected to DCS control system through cable, the oil filter provides negative pressure suction through vacuum pump, set up manual inlet valve on the oil inlet of the oil filter, and its oil outlet is connected with the oil tank through oil filter oil return pipeline, set up first check valve on the oil outlet of the oil filter, set up blowdown pipeline on the bottom of the oil tank, and set up first shutoff valve on it, the filter oil supply pipeline is connected with the filter oil supply pipeline through the three -way of no. 1 on the blowdown pipeline, the filter oil supply pipeline adopts the metal hose of loose joint, and both ends are connected with the import of the three -way of no. 1, the import of manual inlet valve respectively through the internal thread loose joint, the three -way of no. 1 is located at the export side of first shutoff valve, set up first hand valve, first solenoid valve respectively on the filter oil supply pipeline, set up second hand valve on the blowdown pipeline located at the export side of first shutoff valve, the first solenoid valve is connected to DCS control system through wireless two-way controller and is linked with liquid level sensor signal control, realizes oil level automatic regulation.

[0007] As the further supplementary explanation of the above technical scheme, install the differential pressure transmitter parallel with the first solenoid valve on the filter oil supply pipeline, the differential pressure transmitter is communicated in real time with DCS control system through wireless two-way controller and forms differential pressure linkage control with the first solenoid valve.

[0008] As the further supplementary explanation of the above technical scheme, the filter oil supply pipeline is connected with the oil supplement pipeline through the three -way of no. 2 on the filter oil supply pipeline, the oil supplement pipeline is connected with the oil drum outside, install second solenoid valve on the oil supplement pipeline, install second shutoff valve on the export of the oil drum, the second solenoid valve is communicated in real time with DCS control system through wireless two-way controller and forms oil level signal linkage, ensures that the oil level is stable.

[0009] As the further supplementary explanation of the above technical scheme, install second check valve on the oil supplement pipeline, the second check valve is located between second solenoid valve and second shutoff valve, for preventing the reverse flow of oil liquid into the oil drum.

[0010] As the further supplementary explanation of the above technical scheme, the oil supplement pipeline is communicated with the filter oil supply pipeline through the bypass pipeline, one end of the bypass pipeline is connected in the import side of second solenoid valve through flange interface, the other end is connected in the import side of first solenoid valve through flange interface, install manual switch valve on the bypass pipeline, the manual switch valve is used for manually switching the oil circuit in the emergency.

[0011] As a further supplementary description of the above technical solutions, the on-site protection circuit of the vacuum pump is composed of an intermediate relay, a contactor and an on-site emergency stop button, the intermediate relay communicates with the DCS control system in real time through a wireless two-way controller, and the contactor coil is controlled to be turned on or turned off, so that the power supply of the oil filter is controlled.

[0012] As a further explanation and limitation of the above technical solutions, the wireless two-way controller is a four-way fixed two-way feedback controller of model HK-FKGD40, and its working voltage is 12V, 24V, 220V or 380V, the transmission frequency is 420MHz-450MHz, the output mode is passive normally open / closed output, and frequency adjustment, mode adjustment and master-slave mode setting are supported.

[0013] Compared with the prior art, the utility model has the following advantages:

[0014] The utility model discloses a filter pipeline is transformed into '' galvanized steel pipe + high temperature and high pressure metal hose live joint '' structure, eliminates the pipeline leakage risk from the root, guarantees the long -term stable operation of filter system. Meanwhile, through setting first solenoid valve and liquid level sensor linkage mechanism on filter oil supply pipeline, can when oil tank oil level is below the preset threshold, through DCS system 50ms instruction solenoid valve closes, and in 5s, filter oil machine power is cut off, avoids the damage of filter oil machine dry operation or steam turbine lubricating system pressure loss caused by oil level too low and other secondary failures, realizes the quick intervention and automation protection of oil leakage initial stage.

[0015] The utility model discloses that the differential pressure transmitter is connected in parallel on filter oil supply pipeline, and the differential pressure transmitter and first solenoid valve form linkage control, when filter core is blocked or oil flow is abnormal and leads to pressure difference to exceed preset value, can through DCS system automatic regulation solenoid valve opening to balance pressure, or trigger sound light alarm and prompt on -the -spot personnel to clean / replacement filter core. Therefore, this system transformation breaks through the limitation of traditional system only relying on manual inspection, realizes the whole process automation control of '' monitoring-regulation-alarm '', effectively prevents the pipeline damage or equipment failure caused by pressure abnormality, improves the stability and operation and maintenance efficiency of system operation.

[0016] The utility model discloses through the linkage design of oil supplement pipeline and filter oil machine vacuum pump, and the oil supplement pipeline is connected with the oil drum, through the linkage of second solenoid valve and DCS, can automatically supplement oil when oil level is below threshold, realizes oil purification and automatic control double functions in the process of supplementing oil: using filter oil machine negative pressure to suck the oil liquid of oil drum and filters the impurities synchronously, avoids the mixing of unfiltered oil liquid caused by traditional direct supplement, saves the cost of adding oil supplement pump at the same time, cooperates with the dynamic regulation of DCS system and starts and stops supplementing oil, and the filter oil machine removes the bubbles and trace water in crude oil, can guarantee the quality of supplementing lubricating oil. Meanwhile, the second check valve is arranged on the oil supplement pipeline, effectively prevents the backflow of oil liquid and pollutes the oil drum, and guarantees the system airtightness.

[0017] The utility model discloses through increasing bypass and manual switching valve, can switch to manual mode when the first electromagnetic valve failure, through the DCS manual control oil circuit conduction, form " automatic control + manual emergency " dual mode, further perfects oil level stable control and emergency ability of failure.

[0018] The utility model discloses a wireless bidirectional controller realizes the remote linkage control of full system equipment. The controller supports multiple voltage input and frequency adjustment, through passive always open / always closed output mode, accurate control electromagnetic valve, differential pressure transmitter and on -the -spot protection circuit's start -stop and state feedback. The operator can monitor oil level, pressure and other key parameters in real time through the DCS system, and the remote switching protection program is executed and emergency operation is carried out, completely change the low -efficiency mode of traditional system dependence field manual control, and the automation level of power plant operation and maintenance is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is the structural diagram of oil level linkage protection device of the utility model in the transformation.

[0020] In the drawing: oil tank is 1, oil filter machine is 2, vacuum pump is 201, manual import valve is 202, first check valve is 203, first shutoff valve is 3, three-way valve is 4, first manual valve is 5, second manual valve is 6, first electromagnetic valve is 7, wireless bidirectional controller is 8, differential pressure transmitter is 9, second three-way valve is 10, oil drum is 11, second electromagnetic valve is 12, second check valve is 13, second shutoff valve is 14, manual switching valve is 15.

[0021] Among them, filter oil return oil pipeline is 100, blowdown pipeline is 200, filter oil oil supply pipeline is 300, oil supplement pipeline is 400, bypass pipeline is 500. DETAILED DESCRIPTION

[0022] In order to further illustrate the technical scheme of the utility model, below combining actual reconstruction construction process and design scheme, we further illustrate the utility model through three embodiments.

[0023] As attached Figure 1As shown, the existing lubricating oil filtration system mainly includes an oil tank 1 and an oil filter 2. A liquid level sensor is installed on the oil tank 1, and its signal output end is connected to the DCS control system through a cable. The oil filter 2 is provided with negative pressure suction by a vacuum pump 201. A manual inlet valve 202 is arranged on the oil inlet of the oil filter 2, and the oil outlet is connected to the oil tank 1 through an oil filter return oil pipeline 100. A first check valve 203 is arranged on the oil outlet of the oil filter 2. A blowdown pipeline 200 is arranged at the bottom of the oil tank 1, and a first shut-off valve 3 is arranged on the blowdown pipeline 200. A filter oil supply pipeline 300 is connected to the oil inlet of the oil filter 2 through a No. 1 three-way pipe 4 on the blowdown pipeline 200. A first manual valve 5 is arranged on the filter oil supply pipeline 300, thereby forming a filter oil circulation system. The No. 1 three-way pipe 4 is located on the outlet side of the first shut-off valve 3. A second manual valve 6 is arranged on the blowdown pipeline 200 on the outlet side of the first shut-off valve 3. The blowdown flow can be adjusted through the second manual valve 6 to ensure independent control of the filter oil operation and the blowdown function. Embodiment 1

[0024] A steam turbine filter oil supply pipeline hardening and oil level linkage protection device is provided. On the basis of the original lubricating oil filtration system pipeline arrangement, the following specific modification scheme is mainly used: the filter oil supply pipeline 300 adopts a live connection metal hose. The main body adopts a DN20 galvanized steel pipe. The two ends are connected to the No. 1 three-way pipe 4 inlet and the manual inlet valve 202 of the oil filter 2 through internal thread live connection high-temperature and high-pressure metal hoses. The interface is wrapped with raw material belt 3 for 3-5 circles of sealing, and is fixed with a pipe clamp. Of course, the pipeline slope is preferably 3%, inclined along the oil flow direction. A first electromagnetic valve 7 is arranged on the filter oil supply pipeline 300. The first electromagnetic valve 7 enters the DCS control system through a wireless two-way controller 8. The DCS control system sets an oil level protection switching switch and a low oil level threshold value (such as 30% of the full oil level of the oil tank). When the oil level is lower than the threshold value and the switching switch is “turned on”, the DCS sends a signal to the wireless controller 8 to make the first electromagnetic valve 7 lose power and close, and at the same time triggers the local protection circuit to cut off the power supply of the oil filter 2. The local protection circuit of the vacuum pump 201 is composed of an intermediate relay, a contactor and a local emergency stop button. The intermediate relay communicates with the DCS control system in real time through the wireless two-way controller 8, and controls the contactor coil on and off, thereby controlling the power supply of the oil filter. Embodiment 2

[0025] To prevent filter core blockage or abnormal oil flow caused by pressure fluctuation, on the basis of embodiment 1, we install a differential pressure transmitter 9 on the oil filter supply pipeline 300, which is connected in parallel with the first solenoid valve 7 to form a double control node. The differential pressure transmitter 9 communicates in real time with the DCS control system through the wireless two-way controller 8. The differential pressure transmitter 9 monitors the pipeline pressure in real time. When the pressure difference exceeds the preset value (such as 0.3 MPa), when the filter core is blocked and the pressure difference exceeds the threshold value, the transmitter sends a signal to the DCS, triggering a double response mechanism: one is that the DCS automatically adjusts the opening degree of the first solenoid valve to try to balance the pipeline pressure; the second is to issue an audible and light alarm to prompt the on-site personnel to clean or replace the filter core. If the pressure continues to be abnormal, the DCS can further instruct to close the solenoid valve and suspend the oil filtering operation to avoid structural damage to the pipeline and equipment caused by high pressure, and realize the whole process automation control of "monitoring-regulation-alarm". Embodiment 3

[0026] To ensure stable oil level and respond to emergency conditions, we connect a oil supplement pipeline 400 to the oil filter supply pipeline 300 through a No. 2 three-way valve 10, and the oil supplement pipeline 400 is externally connected to an oil tank 11. A second check valve 13 is installed on the oil supplement pipeline 400, which is located between the second solenoid valve 12 and the second shut-off valve 14, used to prevent oil from flowing back into the oil tank 11. A second solenoid valve 12 is installed on the oil supplement pipeline 400, which is linked with the DCS through a wireless two-way controller 8. When the oil level is below the threshold and needs to be supplemented, the on-site personnel input a 6-digit password to close the protection switching switch on the DCS, and then instruct the second solenoid valve 12 to open, start the vacuum pump 201 to extract oil from the oil tank 11 and supplement it to the oil tank 1, and automatically restore the protection program when the oil level meets the standard, ensuring stable oil level.

[0027] Further, the oil supplement pipeline 400 and the oil filter supply pipeline 300 are connected through a bypass pipeline 500. One end of the bypass pipeline 500 is connected through a flange interface on the inlet side of the second solenoid valve 12, and the other end is connected through a flange interface on the inlet side of the first solenoid valve 7. A manual switch valve 15 is installed on the bypass pipeline 500. When the first solenoid valve 7 fails, the switch valve 15 can be manually opened to directly connect the oil inlet of the oil filter 2 through the bypass pipeline 500, and cooperate with the DCS to manually control the second solenoid valve 12 to maintain the oil circuit conduction, realizing the dual-mode redundancy of "automatic control + manual emergency", ensuring the safe operation of the system in fault state.

[0028] In the above embodiment, the wireless two-way controller 8 is a four-way fixed two-way feedback controller of model HK-FKGD40, which is a purchased shaped device and is installed by guide rail. The working voltage of the wireless two-way controller is 12V, 24V, 220V or 380V, the transmitting frequency is 420MHz-450MHz, the output mode is passive normally open / closed output, and frequency adjustment (in the range of 420-450MHz), mode adjustment (self-locking, point operation) and master-slave mode setting are supported.

[0029] Its working principle and operation mode are as follows:

[0030] When the oil filter runs normally, the first shut-off valve 3 is normally open, the second manual valve 6, the second shut-off valve 14 and the manual switching valve 15 are all closed, the field worker needs to input the oil level protection value (for example, set to 250mm) in the DCS system and put into the protection program, and at the same time, the wireless controller 8 is switched to "automatic mode". Then manually open the first manual valve 5, close the second manual valve 6, and confirm that the oil filter oil supply pipeline 300 is unobstructed, then manually open the first electromagnetic valve 7 and close the second electromagnetic valve 12 through the DCS interface, at this time, the vacuum pump 201 of the oil filter 2 starts to work, and the oil filtering operation is formally started. During the oil filtering process, the field worker needs to monitor the DCS picture in real time, closely observe the oil level curve and the state of the electromagnetic valve, and at the same time, ensure that the oil temperature at the outlet of the oil filter is controlled within the range of 40-50℃, if abnormality is found, the pipeline or equipment operation condition needs to be checked in time.

[0031] When the oil tank oil level is lower than the preset protection value, the liquid level sensor will immediately transmit the signal to the DCS system, the system will automatically pop up an alarm window and trigger a voice prompt to remind the field worker that the oil level is abnormal. After receiving the signal, the DCS system will send an instruction to the first electromagnetic valve 7 through the wireless controller 8 within 50ms, quickly cutting off the oil inlet pipeline of the oil filter 2. At the same time, the intermediate relay in the local protection circuit is disconnected, the contactor is released, and the oil filter 2 stops running within 5s, avoiding the aggravation of oil leakage or damage to the equipment caused by empty pumping. At this time, the field worker needs to immediately check the oil level on site to check whether there is pipeline leakage or equipment oil leakage, etc., and after repair, manually supplement oil to above the protection value, reset the protection program in the DCS system, and re-input the oil filtering operation.

[0032] When the oil tank oil level is lower than the preset protection value, oil needs to be added, the field staff closes the oil level protection switching switch in the DCS system and inputs a 6-digit operator password for confirmation to prevent misoperation from causing safety hazards. Subsequently, pipeline connection is carried out, the first electromagnetic valve 7 is manually closed, the second electromagnetic valve 12 is opened, and the vacuum pump 201 of the oil filter 2 is started again, oil in the oil drum is started to be extracted for oil addition, the field staff needs to continuously observe the change of the oil level data in the DCS picture, and after the oil level reaches the target value, the oil filter 2 is stopped in time and the second electromagnetic valve 12 is closed, and the oil level protection program is re-input.

[0033] If an emergency occurs during the oil filtering process, such as a first electromagnetic valve equipment failure, the field staff can switch to the manual mode in the DCS system, open the manual switching valve 15 on site, quickly switch to the manual mode, directly connect the oil inlet of the oil filter 2 through the bypass pipeline 500, at this time the second electromagnetic valve 12 is maintained in the open state, the oil is supplied through the DCS manual control oil addition pipeline 400, the oil circuit switching is stable, and the oil level and equipment running state are closely monitored to avoid oil level fluctuation or equipment damage caused by switching. After the fault is eliminated, the automatic mode is restored, the protection value is re-set, and the system is ensured to be safe and stable.

[0034] The main features and advantages of the present application are shown and described above, and for those skilled in the art, it is obvious that the specific embodiments of the present application are not limited to the details of the above exemplary embodiments, and the inventive idea and design idea of the present application can be realized in other specific forms without departing from the spirit or basic characteristics of the present application, which should be equivalent to the protection scope disclosed in the technical scheme of the present application. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

[0035] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description manner of the specification is only for the sake of clarity, those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A steam engine oil filter oil supply pipeline hardening and oil level linkage protection device, comprising an oil tank (1) and an oil filter (2), a liquid level sensor is installed on the oil tank (1), the signal output end of the liquid level sensor is connected to a DCS control system through a cable, the oil filter (2) provides negative pressure suction through a vacuum pump (201), a manual inlet valve (202) is arranged on the oil inlet of the oil filter (2), the oil outlet of the oil filter (2) is connected with the oil tank (1) through an oil filter return oil pipeline (100), a first check valve (203) is arranged on the oil outlet of the oil filter (2), a blowdown pipeline (200) is arranged at the bottom of the oil tank (1), a first shut-off valve (3) is arranged on the blowdown pipeline (200), characterized in that: A filter oil supply pipeline (300) is connected to the blowdown pipeline (200) through a No. 1 tee (4), the filter oil supply pipeline (300) adopts a loose joint connecting metal hose, and the two ends thereof are connected to the inlet of the No. 1 tee (4) and the inlet of the manual inlet valve (202) through internal thread loose joints respectively, the No. 1 tee (4) is located at the outlet side of the first shut-off valve (3), a first manual valve (5) and a first electromagnetic valve (7) are arranged on the filter oil supply pipeline (300) respectively, a second manual valve (6) is arranged on the blowdown pipeline (200) at the outlet side of the first shut-off valve (3), the first electromagnetic valve (7) is connected to the DCS control system through a wireless two-way controller (8) and is controlled in linkage with a liquid level sensor signal to realize automatic adjustment of the oil level.

2. A steam turbine oil filter and oil supply line hardening and oil level interlock protection device according to claim 1, characterized in that: A differential pressure transmitter (9) is arranged on the filter oil supply pipeline (300) in parallel with the first electromagnetic valve (7), the differential pressure transmitter (9) is in real-time communication with the DCS control system through the wireless two-way controller (8) and forms differential pressure linkage control with the first electromagnetic valve (7).

3. A hardening and oil level linkage protection device for an oil filter feed line of a steam turbine as set forth in claim 2, wherein: An oil supplement pipeline (400) is connected to the filter oil supply pipeline (300) through a No. 2 tee (10), the oil supplement pipeline (400) is externally connected to an oil tank (11), a second electromagnetic valve (12) is arranged on the oil supplement pipeline (400), a second shut-off valve (14) is arranged on the outlet of the oil tank (11), the second electromagnetic valve (12) is in real-time communication with the DCS control system through the wireless two-way controller (8) to form oil level signal linkage and ensure stable oil level.

4. A hardening and oil level linkage protection device for an oil filter feed line of a steam turbine as set forth in claim 3, wherein: A second check valve (13) is arranged on the oil supplement pipeline (400), the second check valve (13) is located between the second electromagnetic valve (12) and the second shut-off valve (14) and is used for preventing reverse flow of oil into the oil tank (11).

5. A steam turbine oil filter and oil supply line hardening and oil level interlock protection device according to claim 4, characterized in that: The oil supplement pipeline (400) and the filter oil supply pipeline (300) are connected in communication through a bypass pipeline (500), one end of the bypass pipeline (500) is connected to the inlet side of the second electromagnetic valve (12) through a flange interface, the other end thereof is connected to the inlet side of the first electromagnetic valve (7) through a flange interface, and a manual switching valve (15) is arranged on the bypass pipeline (500), the manual switching valve (15) is used for manually switching the oil circuit in an emergency.

6. A steam turbine oil filter and oil supply line hardening and oil level interlock protection device according to any one of claims 1 to 5, characterized in that: The local protection circuit of the vacuum pump (201) is composed of an intermediate relay, a contactor and a local emergency stop button, the intermediate relay is in real-time communication with the DCS control system through the wireless two-way controller (8) and controls the power supply of the oil filter by controlling the on-off of the contactor coil.

7. A steam turbine oil filter and oil supply line hardening and oil level interlock protection device according to claim 6, characterized in that: The wireless two-way controller (8) is a four-way fixed two-way feedback controller of model HK-FKGD40, the working voltage thereof is 12V, 24V, 220V or 380V, the transmission frequency thereof is 420MHz-450MHz, the output mode thereof is passive normally open / closed output, and the wireless two-way controller (8) supports frequency adjustment, mode adjustment and master-slave mode setting.

Images