Device for testing leakage of condensation pump and ensuring vacuum

Abstract

The utility model relates to a condensation pump, in particular to a vacuum device for leakage test of the condensation pump. Comprising an operation pump and a standby pump. Both are connected with an inlet pipeline and an outlet pipeline; root valves are arranged on the two inlet pipelines; the root valve is positioned between the pump body and the inlet valve; check valves are arranged on the two outlet pipelines; the check valve is arranged between the pump body and the outlet valve; the two outlet pipelines are connected with bypass valves; the bypass valve is connected with the check valve in parallel; the two inlet pipelines and the second inlet pipeline are connected with a before-pump pressure gauge; the before-pump pressure gauge is positioned between the root valve and the pump body; the problems that after the standby pump is overhauled, emptying is not thorough after pump filling of the standby pump, air reversely flows back to an inlet of a running pump body, and air binding of an existing running pump is caused are solved. The method is suitable for pump body leakage detection and normal switching after double-pump deployment and maintenance of a single condensation pump in the operation process of a large turboset.

Description

Technical Field

[0001] The utility model relates to a condensate pump, in particular to a device for ensuring vacuum during the leak test of a condensate pump. Background Technique

[0002] The condensate pump relies on centrifugal force to press a certain mass of liquid out of the impeller to form a local vacuum. Under the action of the local pressure difference, the liquid is sucked into the pump and forms a continuous flow. Usually, two steam turbine condensate pumps are installed at the same time, and one is in operation and the other is in standby during normal operation. If one of the pumps stops due to reasons such as mechanical seal leakage or excessive bearing vibration, the inlet and outlet valves are closed for isolation and maintenance. After the maintenance is completed, due to incomplete evacuation after the standby pump is primed, it cannot be normally put into standby. Moreover, during the process of testing and putting the standby pump into standby, due to the reverse flow of air back into the pump body inlet, it is easy to cause air binding of the currently operating pump, resulting in fluctuations in the outlet pressure, and further affecting the normal operation of the steam turbine or even causing it to stop operating passively.

[0003] After the maintenance of the standby pump is completed, the conventional operation is to open the inlet valve of the condensate pump to prime the repaired pump. After priming, open the pump inlet exhaust valve and the pump body exhaust valve to exhaust air from the condensate pump inlet pipeline. Since the inlet of the condensate pump is in a negative pressure state, the air in the pump body reversely fills into the condensate, making the condensate at the inlet of the operating pump contain air, which is extremely likely to cause air binding of the operating pump, resulting in the operating pump not discharging properly, fluctuations in the outlet pressure, and an increase in the hot well liquid level, affecting the stable operation of the steam turbine unit. Content of the Utility Model

[0004] The utility model overcomes the deficiencies of the prior art and provides a device for ensuring vacuum during the leak test of a condensate pump, which solves the problem that after the maintenance of the standby pump is completed, the evacuation is not thorough after the standby pump is primed, and the reverse flow of air back into the inlet of the operating pump body causes air binding of the currently operating pump.

[0005] In order to achieve the above object, the utility model is realized by the following technical solutions:

[0006] A device for ensuring vacuum during leak testing of a condensate pump, comprising two condensate pumps, one condensate pump serving as the operating pump and the other condensate pump serving as the standby pump; the steam condensate pipeline is connected to the inlet end of the operating pump through the first inlet pipeline, and the steam condensate pipeline is connected to the inlet end of the standby pump through the second inlet pipeline; the outlet end of the operating pump is connected to the condensate external delivery pipeline through the first outlet pipeline, and the outlet end of the standby pump is connected to the condensate external delivery pipeline through the second outlet pipeline; an inlet valve is provided on both the first inlet pipeline and the second inlet pipeline; an outlet valve is provided on both the first outlet pipeline and the second outlet pipeline; a root valve is provided on both the first inlet pipeline and the second inlet pipeline; the root valve is located between the pump body and the inlet valve; a check valve is provided on both the first outlet pipeline and the second outlet pipeline; the check valve is provided between the pump body and the outlet valve; a bypass valve is connected to both the first outlet pipeline and the second outlet pipeline; the bypass valve is connected in parallel with the check valve; a pre-pump pressure gauge is connected to both the first inlet pipeline and the second inlet pipeline, and the pre-pump pressure gauge is located between the root valve and the pump body.

[0007] Further, a pump outlet pressure gauge is connected to both the first outlet pipeline and the second outlet pipeline, and the pump outlet pressure gauge is located between the check valve and the pump body.

[0008] Further, the first inlet pipeline and the second inlet pipeline are respectively connected with a pre-pump exhaust pipeline, and the two pre-pump exhaust pipelines are connected in parallel and then connected to the condenser.

[0009] Furthermore, the pre-pump exhaust pipeline is connected between the pre-pump pressure gauge and the pump body.

[0010] Furthermore, a pre-pump exhaust valve is provided on the pre-pump exhaust pipeline.

[0011] The beneficial effects of the present utility model compared with the prior art are as follows:

[0012] The present utility model adds a cross-connecting valve before and after the check valve at the outlet of the condensate pump, and adds a local pressure gauge at the inlet. After adding the cross-connecting valve, slightly open the outlet valve, and through the cross-connecting valve, the pump can be quickly primed to discharge the gas in the pump, preventing the phenomena of air extraction and the pump not discharging. Adding a local pressure gauge on the inlet pipe can more intuitively understand the air pressure in the pump, timely adjust the opening of the outlet valve, ensure the normal operation of the operating pump during the start-up and repair of the standby pump, and ensure the stable operation of the steam turbine unit.

[0013] After adding a jumper bypass valve at the check valve at the outlet of the condensate pump, after the standby pump is repaired, open the outlet valve of the standby pump, and reverse the pressurized condensate back into the pump body through the jumper pipeline of the outlet check valve for priming the pump. Add a pressure gauge branch line after the inlet valve of the inlet pipe. When priming the pump, remove the pressure gauge and open the root valve to exhaust the air from the pump body. After the exhaust is completed, install a positive pressure gauge and conduct a leak test on the pump body. Through the positive pressure gauge, the air pressure inside the standby pump after maintenance can be more intuitively understood, and the opening degree of the outlet valve can be adjusted in a timely manner to observe the sealing condition of the standby pump. At the same time, ensure the normal operation of the running pump and do not affect the stable operation of subsequent working conditions.

[0014] After the leak check of the standby pump is normal, open the condensate inlet valve of the standby pump, close the jumper of the check valve of the standby pump, and perform the pump starting operation. The outlet pressure of the standby pump is normal, and the running pump is normally switched to the standby pump. Close the root valve of the inlet pressure gauge and replace it with a vacuum pressure gauge. After replacement, open the root valve and use the vacuum gauge to monitor in real time to observe the vacuum degree at the inlet of the condensate pump. Keep one pump running and one pump in standby to maintain the normal operation of the steam turbine unit.

[0015] The utility model is applicable to the leak check of the pump body and the normal switching after the repair of a single condensate pump in the dual-pump deployment during the operation of a large steam turbine unit. Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of the condensate pump leak test and vacuum guarantee device of the utility model;

[0017] In the figure:

[0018] 1 - running pump; 2 - standby pump; 3 - steam condensate pipeline; 4 - first inlet pipeline; 5 - second inlet pipeline; 6 - first outlet pipeline; 7 - condensate external delivery pipeline; 8 - second outlet pipeline; 9 - inlet valve; 10 - outlet valve; 11 - root valve; 12 - check valve; 13 - bypass valve; 14 - pressure gauge in front of the pump; 15 - pressure gauge at the pump outlet; 16 - exhaust pipeline in front of the pump; 17 - condenser inlet pipeline; 18 - exhaust valve in front of the pump. Detailed Embodiments

[0019] In order to make the technical problems, technical solutions and beneficial effects to be solved by the utility model clearer, the utility model is further described in detail below in combination with embodiments and drawings. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model. The technical solutions of the utility model are described in detail below in combination with embodiments and drawings, but the protection scope is not limited by this.

[0020] See Figure 1, this embodiment proposes a device for ensuring vacuum during the leak test of a condensate pump, which includes two condensate pumps. One condensate pump serves as the operating pump 1, and the other condensate pump serves as the standby pump 2; when the two condensate pumps are operating normally, one is in use and the other is in standby.

[0021] The steam condensate pipeline 3 is connected to the inlet end of the operating pump 1 through the first inlet pipeline 4, and the steam condensate pipeline 3 is connected to the inlet end of the standby pump 2 through the second inlet pipeline 5; the outlet end of the operating pump 1 is connected to the condensate external delivery pipeline 7 through the first outlet pipeline 6, and the outlet end of the standby pump 2 is connected to the condensate external delivery pipeline 7 through the second outlet pipeline 8; the first inlet pipeline 4 and the second inlet pipeline 5 are both provided with inlet valves 9; the first outlet pipeline 6 and the second outlet pipeline 8 are both provided with outlet valves 10. The steam condensate from the condenser can enter the operating pump 1 through the first inlet pipeline 4. Similarly, the steam condensate from the condenser can enter the standby pump 2 through the second inlet pipeline 5; the condensate is sent to the pipe network through the first outlet pipeline 6 or the second outlet pipeline 8 by the operating pump 1 or the standby pump 2.

[0022] To prevent air from getting trapped in the pipeline, the first inlet pipeline 4 and the second inlet pipeline 5 are respectively connected with exhaust pipelines 16 in front of the pumps. The two exhaust pipelines 16 in front of the pumps are connected in parallel and then connected to the condenser inlet pipeline 17, and finally sent to the condenser. The exhaust pipeline 16 in front of the pump is connected between the pressure gauge 14 in front of the pump and the pump body, and the exhaust valve 18 in front of the pump is provided on the exhaust pipeline 16 in front of the pump.

[0023] The first inlet pipeline 4 and the second inlet pipeline 5 are both provided with root valves 11; the root valves 11 are located between the pump body and the inlet valve 9; the first outlet pipeline 6 and the second outlet pipeline 8 are both provided with check valves 12; the check valves 12 are arranged between the pump body and the outlet valve 10; the first outlet pipeline 6 and the second outlet pipeline 8 are both connected with bypass valves 13; the bypass valves 13 are connected in parallel with the check valves 12. The first outlet pipeline 6 and the second outlet pipeline 8 are both connected with pressure gauges 15 at the pump outlet, and the pressure gauges 15 at the pump outlet are located between the check valves 12 and the pump body.

[0024] The first inlet pipeline 4 and the second inlet pipeline 5 are both connected with pressure gauges 14 in front of the pumps, and the pressure gauges 14 in front of the pumps are located between the root valves 11 and the pump body.

[0025] The working principle of the device for ensuring vacuum during the leak test of a condensate pump described in this embodiment is as follows:

[0026] After the maintenance of the standby pump 2 is completed, the normal operation is to open the inlet valve 9 of the standby pump 2 to fill the standby pump 2 with liquid. After filling, open the exhaust valve 18 in front of the pump at the inlet of the standby pump 2 to exhaust the gas in the exhaust pipeline 16 in front of the standby pump 2. Since the inlet of the operating pump 1 is in a negative pressure state at this time, the air in the operating pump 1 reversely fills the condensate, making the condensate at the inlet of the operating pump 1 contain air, which is extremely likely to cause the phenomenon of air binding in the operating pump 1, resulting in the operating pump 1 not discharging properly, the outlet pressure fluctuating, and the hot well liquid level rising, affecting the stable operation of the steam turbine unit.

[0027] In the device of this embodiment, bypass valves 13 are connected to both the first outlet pipeline 6 and the second outlet pipeline 8. After the maintenance of the standby pump 2 is completed, open the outlet valve 10 of the standby pump 2, and reverse the pressurized condensate back into the pump body of the standby pump 2 through the reverse connection pipeline of the check valve 12 of the standby pump 2 for liquid filling. Since a pressure gauge 14 in front of the pump is connected to the second inlet pipeline 5, remove the pressure gauge 14 in front of the pump on the second inlet pipeline 5 during liquid filling, open the root valve 11 on the second inlet pipeline 5 to exhaust the gas from the pump body. After the exhaust is completed, install the pressure gauge 14 in front of the pump and conduct a leak check on the pump body. Through the pressure gauge 14 in front of the pump, the air pressure in the pump body of the standby pump 2 after maintenance can be more intuitively understood, the opening degree of the outlet valve can be adjusted in time to observe the sealing condition of the standby pump 2, and at the same time, ensure the normal operation of the operating pump and do not affect the stable operation of the subsequent working conditions.

[0028] After the leak check of the standby pump 2 is normal, open the inlet valve 9 of the standby pump 2, close the bypass valve 13 bypassed by the check valve of the standby pump 2, and perform the operation of starting the pump. The outlet pressure of the standby pump 2 is normal, and the operating pump 1 is normally switched to the standby pump 2. Close the root valve 11 of the pressure gauge at the inlet of the standby pump 2 and replace it with a vacuum gauge. After replacement, open the root valve 11 and use the vacuum gauge to monitor in real time to observe the vacuum degree at the inlet of the condensate pump. The two pumps are kept in a state of one running and one standby to maintain the normal operation of the steam turbine unit.

[0029] This device solves the problem that during the operation of the steam turbine unit, when one pump fails, stops for maintenance, and then starts again, it causes fluctuations and impacts on the operating conditions of the steam turbine unit and even causes the unit to trip. After the maintenance of the standby pump, it can quickly check for leaks, fill with liquid, and be put into normal standby, reducing the risk of system shutdown due to working condition fluctuations and ensuring the stable operation of the steam turbine. The utility model is applicable to the leak check of the pump body and normal switching after the maintenance of a single condensate pump in the double-pump deployment during the operation of a large steam turbine unit.

[0030] The above content is a further detailed description of the present utility model in combination with specific preferred embodiments. It cannot be determined that the specific embodiments of the present utility model are limited to this. For those of ordinary skill in the technical field to which the present utility model belongs, without departing from the premise of the present utility model, several simple deductions or replacements can still be made, which should all be regarded as belonging to the patent protection scope determined by the claims submitted for the present utility model.

Claims

1. A device for ensuring vacuum during the leak test of a condensate pump, comprising two condensate pumps, one condensate pump serving as an operating pump (1) and the other condensate pump serving as a standby pump (2); a steam condensate pipeline (3) is connected to the inlet end of the operating pump (1) through a first inlet pipeline (4), and the steam condensate pipeline (3) is connected to the inlet end of the standby pump (2) through a second inlet pipeline (5); the outlet end of the operating pump (1) is connected to a condensate external delivery pipeline (7) through a first outlet pipeline (6), and the outlet end of the standby pump (2) is connected to the condensate external delivery pipeline (7) through a second outlet pipeline (8); an inlet valve (9) is provided on both the first inlet pipeline (4) and the second inlet pipeline (5); an outlet valve (10) is provided on both the first outlet pipeline (6) and the second outlet pipeline (8); it is characterized in that, Both the first inlet pipeline (4) and the second inlet pipeline (5) are provided with root valves (11); the root valves (11) are located between the pump body and the inlet valve (9); both the first outlet pipeline (6) and the second outlet pipeline (8) are provided with check valves (12); the check valves (12) are arranged between the pump body and the outlet valve (10); both the first outlet pipeline (6) and the second outlet pipeline (8) are connected with bypass valves (13); the bypass valves (13) are connected in parallel with the check valves (12); both the first inlet pipeline (4) and the second inlet pipeline (5) are connected with pre-pump pressure gauges (14), and the pre-pump pressure gauges (14) are located between the root valves (11) and the pump body.

2. The device for ensuring vacuum in leak testing of a condensate pump according to claim 1, characterized in that, Both the first outlet pipeline (6) and the second outlet pipeline (8) are connected with post-pump pressure gauges (15), and the post-pump pressure gauges (15) are located between the check valves (12) and the pump body.

3. The device for ensuring vacuum during the leak test of a condensate pump according to claim 2, characterized in that, The first inlet pipeline (4) and the second inlet pipeline (5) are respectively connected with pre-pump exhaust pipelines (16), and the two pre-pump exhaust pipelines (16) are connected in parallel and then connected to the condenser inlet pipeline (17).

4. A device for ensuring vacuum during leak testing of a condensate pump according to claim 3, characterized in that, The pre-pump exhaust pipeline (16) is connected between the pre-pump pressure gauge (14) and the pump body.

5. The device for ensuring vacuum during leak testing of a condensate pump according to claim 3, characterized in that, The pre-pump exhaust valve (18) is arranged on the pre-pump exhaust pipeline (16).

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