KR20220098866A - High-pressure membrane accumulator test method to secure fuel supply safety for eco-friendly ships - Google Patents

Abstract

The present invention relates to a high-pressure membrane accumulator test method for securing fuel supply safety of an eco-friendly ship, which improves the reliability of a test, comprising: a setting value input step (S1); a test equipment mounting step (S2); a measured value generating step (S3); an error check step (S4); and a step (S5) of checking the number of times of operations.

Description

High-pressure membrane accumulator test method to secure fuel supply safety for eco-friendly ships}

The present invention relates to a high-pressure membrane accumulator testing apparatus for securing fuel supply safety of an eco-friendly vessel to which a dual fuel engine is applied, and more particularly, to a test method for performing a fatigue impact test by applying repeated hydraulic pressure to a membrane accumulator.

In order to respond to the International Maritime Organization (IMO) regulations on marine environmental pollution, dual fuel engines with less pollutant emissions have been developed and are increasingly applied to ships. As the hydraulic system of ultra-high pressure is used, the pulsation and vibration in the hydraulic system become very large.

Accordingly, a membrane accumulator is essential to damp the pressure pulsation occurring in the hydraulic system and to minimize shock and vibration. Problems occur frequently, and since the existing accumulator replacement cycle is estimated to be about 2 years, it is shorter than the engine overhaul cycle of 3 years, so failures often occur before the replacement cycle. As it is a part that causes serious problems that require

Therefore, it is essential to develop a membrane accumulator with improved performance and durability, and in particular, it is necessary to conduct an endurance test under pressure conditions that can ensure long-term durability.

Accordingly, in order to evaluate the reliability of the accumulator, Korean Patent Laid-Open No. 10-2017-0114667 “Accumulator Reliability Testing Equipment” is a test method for controlling the number of tests and a relief valve for applying repeated pressure to the accumulator and preventing overflow. Although the technology has been announced,

Since there is no way to predict that the accumulator to be tested will break during the test, there is a difficulty for a long-term continuous test, and there is a safety problem with respect to the breakage of the high-pressure accumulator during the test.

Therefore, there is a need for a test method for a membrane accumulator that can prepare for not only the durability test of the membrane accumulator to be tested, but also damage to the test target that may occur during the test.

Republic of Korea Patent Publication No. 10-2017-0114667 (2017.10.16.)

The present invention was created to solve the above problems, and an object of the present invention is to supply hydraulic pressure having a constant frequency in order to test the durability of a membrane accumulator, and store the test data to obtain a result value for the durability of the test object. To provide a test method for storing

Objects of the present invention are not limited to the objects mentioned above, and other objects not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

In the high-pressure membrane accumulator durability test method for securing fuel supply safety for eco-friendly ships, a set value including one or more of the maximum/minimum value of supply hydraulic pressure, the frequency of flow, and the number of operations according to the specification of the accumulator to be tested is determined. a setting value input step (S1) to be input to the touch panel 31; The accumulator 10 is mounted in the open space of the jig 11, one side of the accumulator 10 is connected to the hydraulic unit 20, the other side is connected to the pressure sensor 13, and a safety cover 12 ) to secure the accumulator (10) inside the test device mounting step (S2); The hydraulic oil in the storage tank is boosted through the motor pump 21 of the hydraulic unit 20 to supply hydraulic pressure to the accumulator 10, and the pressure sensor 13 to measure the hydraulic pressure supplied to the accumulator 10 a measurement value generating step of outputting a value (S3); an error checking step (S4) of comparing the hydraulic pressure measurement value of the pressure sensor 13 corresponding to the set value with an accumulator endurance test standard and outputting error data; and performing the measurement value generating step (S3) again when the number of operations is not completed, and checking the number of operations (S5) of outputting the completion of the endurance test when the number of operations is completed.

And, in the measurement value generating step (S3), the hydraulic pressure supplied to the accumulator 10 has pulsation and vibration through the proportional control valve 22 that controls the opening and closing of the internal flow path in response to the set value. characterized in that

In addition, after the set value input step (S1), the maximum hydraulic pressure of the hydraulic unit 20 is measured in a no-load state without the accumulator 10, and a test preparation step of checking the measured value corresponding to the set value It is characterized in that it further comprises.

In addition, after the set value input step (S1), the measured values for the temperature, oil pressure, and oil level height of the hydraulic oil of the hydraulic unit 20 and the user-set durability test standard for the oil leakage state of the accumulator have, It characterized in that it further comprises a protection circuit operation step (S6) of stopping the motor pump 21 when the measured value and the oil leakage state deviates from the endurance test standard.

In addition, in the error checking step (S4), it characterized in that it further comprises a PID control step of correcting the set value through the error data and reducing the error between the set value and the measured value.

In addition, in the measurement value generating step (S3), the measurement value communicates with an external PC through the DAQ module 34, and the external PC sets an abnormal signal condition by the pressure deviation of the measurement value, and the An accumulator endurance test method, characterized in that the lifespan of the accumulator (10) is estimated by further including a pressure analysis step of generating an alarm for an abnormal signal.

According to the present invention, there are the following effects.

First, according to the specifications of the accumulator, it is possible to perform an endurance test for hydraulic pressure pulsating at different target pressures.

Second, for the hydraulic pressure generated during the endurance test, the test reliability is improved by correcting the set value for the measured value and delivering the correct hydraulic pressure to the accumulator.

Third, a protection circuit to stop the motor pump by operating in a problem situation of temperature, pressure, and leakage of hydraulic oil that occurs during the endurance test is installed, and a safety cover is provided to prevent damage to the accumulator due to high pressure to protect users from safety accidents. and test subjects can be safely protected.

1 is a perspective view of an accumulator durability testing apparatus according to the present invention.
2 is a schematic diagram of a controller unit according to the present invention.
3 is a block diagram of an accumulator durability testing apparatus according to the present invention.
4 is a graph comparing in real time a set value and a hydraulic pressure measurement value according to the present invention.
5 is a flowchart of an accumulator test according to the present invention.

Advantages and features of the present invention, and a method of achieving them, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

Detailed contents for carrying out the present invention will be described in detail with reference to the accompanying drawings below. Irrespective of the drawings, like reference numbers refer to like elements, and "and/or" includes each and every combination of one or more of the recited items.

The terminology used herein is for the purpose of describing the embodiments, and is not intended to limit the present invention. In this specification, the singular also includes the plural, unless specifically stated otherwise in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components in addition to the stated components.

Unless otherwise defined, all terms (including technical and scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of an accumulator durability testing apparatus according to the present invention.

As shown, in order to execute the durability test of the accumulator 10, a jig 11, a safety cover 12, and an oil leak support 14 are installed on a metal structure to fit the user's eye level. There is an endurance test device that can observe the experimental situation.

The jig 11 is an open space in which the accumulator 10 to be tested can be mounted, the accumulator 10 to be tested is fixed so that it does not move, and a rubber base is provided to fit the size of the accumulator 10. The open space can be expanded or reduced to fit, and the accumulator 10 can be prevented from being damaged in the steel structure.

The hydraulic unit 20 is connected to one side of the accumulator 10, and supplies hydraulic pressure to the accumulator 10 by boosting hydraulic oil in the storage tank through the motor pump 21, and there is vibration generated by using the motor. It is desirable to install it in a place that does not affect the durability test equipment.

In addition, in order to prevent the hydraulic oil in the storage tank from being overheated during the test, it is also possible to design a chiller cooler 24 to control the temperature of the hydraulic oil.

The pressure sensor 13 is connected to the other side of the accumulator 10 , measures the pressure of the hydraulic oil supplied to the accumulator 10 , and is fixed to the steel structure so as not to be shaken.

At this time, the hydraulic pressure measurement value of the pressure sensor 13 can be used as data, and the data utilization of the pressure sensor 13 will be described later.

The safety cover 12 has a shape that surrounds the outer circumferential surface of the accumulator 10 under test at regular intervals, protects the inside against safety accidents that may occur during the test, and allows the user to observe the inside during the test. It is desirable to use a transparent material so that

The oil leak support 14 is installed on the lower part of the jig 11, and the upper surface is opened to form a space to accommodate the oil leakage generated by the accumulator 10 inside. (10) It is desirable to prepare for an accident by installing a hydraulic oil detection sensor that can detect oil leakage because it is a case where there is a gap or is damaged or the hydraulic hose of the hydraulic connection part is damaged.

The controller unit 30 is preferably installed on a flat surface at a predetermined distance from the experimental equipment, and is located at a height that a user can use conveniently.

It is possible to input the set value required for the test, and includes a touch panel 31 that displays the state of the experiment, a power button for the hydraulic unit 20, an emergency stop button that can stop the motor pump 21 in an emergency, and If a problem occurs during the test, there is a buzzer that emits a sound and a lamp that emits light so that the user can know.

In addition, it is possible to collect experimental data in real time by configuring a PC, and data communication of the controller unit 30 will be described later.

2 is a schematic diagram of a controller unit according to the present invention.

The controller unit 30 installs the touch panel 31 on the upper surface, the controller unit 30 power switch, the hydraulic unit motor pump 21 power button, and a lamp for knowing the state of the motor pump 21, the motor pump ( When the emergency stop button and the protection circuit 23 that can stop 21) operate, the situation is notified to the user, including a buzzer that sounds and a lamp that lights up.

In addition, the touch panel 31 allows a user to directly input a set value, and can know the current number of repetitions, the state of the proportional control valve 22 , the current pressure of the accumulator 10 and the operating time.

2 is an example for explaining the present invention, and does not limit the configuration thereof.

3 is a block diagram of an accumulator durability testing apparatus according to the present invention.

As shown, the touch panel 31 is capable of inputting a set value including one or more of the maximum/minimum value of the supply hydraulic pressure required for the test, the frequency of the flow, and the number of operations, and the temperature of the hydraulic oil stored in the hydraulic unit 20 , the maximum hydraulic pressure generated by the motor pump 21, the measured value for the height of the hydraulic oil oil level stored in the storage tank, and the leakage state are displayed, and the user can know in real time whether the durability test is suitable.

The values input to the touch panels 31 and 31, the power button, the emergency stop button, the buzzer and the lamp are electrically communicated through the PLC 32, and the command signal is communicated with the hydraulic valve amplifier 33 at 0 to 10V. do.

The hydraulic valve amplifier 33 outputs a signal of 0V to 10V to the proportional control valve 22 with the set value input through the touch panel 31, and the proportional control valve 22 is internally configured to correspond to the input set value. The hydraulic pressure generated by the motor pump 21 in the hydraulic unit 20 is supplied to the accumulator 10 by controlling the spool for adjusting the opening range of the flow path.

Accordingly, the accumulator 10 may receive hydraulic pressure with pulsation and vibration, which may similarly provide an environment with pulsation of high pressure occurring in an actual field.

The pressure sensor 13 transmits the pressure data measured by the pressure sensor 13 in real time with respect to the maximum/minimum values of the hydraulic pressure supplied to the accumulator 10 and the frequency of the flow, the hydraulic valve amplifier 33 and the DAQ module 34. can be transmitted to, and at this time, one or more pressure sensors 13 may be used.

The DAQ module 34 is a device that collects the pressure data measured by the pressure sensor 13 and transmits and receives data to and from an external PC, and the external PC stores the pressure data through the DAQ module 34 and sends By analyzing the applied hydraulic pressure with software included in the external PC, abnormal conditions due to pressure deviation can be set, and an alarm for an abnormal signal can be generated through the touch panel 31 .

The hydraulic valve amplifier 33 installed in the controller unit 30 receives the hydraulic pressure measurement value from the pressure sensor 13 in real time, and compares the measured value of the pressure sensor 13 with the set value set by the user and compares the error data. The test apparatus of the present invention can secure the reliability of the test data because the PID control to obtain a new output value through the corrected set value by correcting the set value as much as the error through the error data.

And, the temperature of the hydraulic oil in the tank, the maximum value of the hydraulic pressure supplied through the motor pump 21, and the height of the oil level of the hydraulic oil inside the tank through the measuring unit comprised of a thermometer, a pressure gauge, and a level gauge provided in the hydraulic unit 20 are the user If it is out of the normal range compared to the accumulator (10) endurance test standard set by , a cutoff signal is transmitted to the hydraulic valve amplifier (33), an alarm message is displayed to the user through the touch panel (31), and the motor pump (21) and a protection circuit 23 to stop it.

In addition, the protection circuit 23 includes a hydraulic oil detection sensor (not shown) installed on the oil leakage support 14, and includes detection of oil leakage due to product damage during the durability test through the detection sensor.

Durability test criteria may include one or more of the criteria for pressure value, temperature value, and oil level value.

The pressure value is instantaneous when the accumulator 10 is damaged or a gap occurs during the endurance test. For example, when the maximum pressure is 400 bar and the minimum pressure is set to 200 bar, a gap is created in the accumulator 10 When the pressure drops, the minimum pressure drops lower than 200 bar, and instantly falls below 150 bar, so the user can set the cutoff reference value to 190 bar to respond to an accident in which the accumulator 10 is damaged or a gap is created.

Next, as for the temperature value, the temperature of the hydraulic oil increases by the frequency of the operation and flow of the pump during the endurance test. can be lowered

However, if the temperature of the hydraulic oil rises due to the failure of the chiller cooler 24, an accurate test is not performed on the accumulator 10 to be tested. Therefore, the temperature value is determined to be less than or equal to the temperature recommended by the test target accumulator 10 .

In addition, the oil level value is the height of the hydraulic oil used during the endurance test. If the hydraulic oil is insufficient, the pressure does not occur in the valves and hydraulic hoses constituting the accumulator test device, so the pressure rises and falls to provide the frequency of the flow. Since the durability test is not performed properly, always maintain the oil level to match the capacity of the hydraulic tank.

In addition, the state of oil leakage is whether oil leakage is detected, and if oil leakage occurs, the test target accumulator 10 is damaged and the connected hydraulic hose is damaged. Send to (33) and stop the motor pump (21) through the PLC (32).

4 is a simulation graph comparing in real time a set value and a hydraulic pressure measurement value according to the present invention.

As shown, the maximum/minimum values of the supply hydraulic pressure and the frequency of the flow appear.

The graph showing the set value shows that the maximum value of the supply oil pressure is 400 bar, the minimum value of the supply oil pressure is 200 bar, the time for the pressure to decrease from the maximum value to the minimum value is 0.5 seconds to 1 second, and the time for the pressure to increase from the minimum value to the maximum value is also 0.5 seconds to 1 second, which is the same as 1 Hz (hertz) to 2 Hz, and because it repeats 10 million times due to the nature of the accumulator endurance test, it cannot be stored in the PLC 32 or the touch panel. Save and analyze.

However, the suggested setting values are merely examples and may be flexibly changed according to the specifications required by the test target accumulator 10 .

And, since the set value is controlled through the PID control, it can be expected that the hydraulic pressure measurement value for the test target accumulator 10 measured by the pressure sensor 13 is also controlled to a very similar value.

In addition, data can be transmitted to software of an external PC through the DAQ module 34 to output and store graphs of time and pressure.

5 is a flowchart of an accumulator test according to the present invention.

As shown, the high-pressure membrane accumulator durability test for securing fuel supply safety for eco-friendly ships is performed by inputting a set value that meets the specifications of the accumulator 10 (S1), installing the test device (S2), measuring the hydraulic pressure (S3), and error Check (S4) and check the number of operations (S5) to test.

First, the set value input step (S1) of inputting a set value including one or more of the maximum/minimum value of the supply hydraulic pressure, the frequency of the flow, and the number of operations to the touch panel 31 according to the specification of the accumulator 10 to be tested carry out

After inputting the set value (S1), close the valve between the outlet of the accumulator 10 and the hydraulic unit 20, measure the maximum hydraulic pressure of the hydraulic unit 20 in a no-load state without the accumulator 10, and set Through the test preparation step (not shown) of checking the operating state of the proportional control valve 22 corresponding to the set value input in the value input step, accidents can be prevented and the reliability of the test can be improved.

In addition, the user has the durability test standard set by the user for the measured values for the temperature, hydraulic pressure, and oil level height of the hydraulic oil of the hydraulic unit 20 and the oil leakage state of the accumulator 10, but the measured values and the oil leakage state are In case of deviating from the endurance test standard, a protection circuit operation step (S6) of stopping the motor pump 21 is additionally included to protect the user and the test device so that a safe test can be performed.

Next, the accumulator 10 is mounted into the open space of the jig 11 , and one side of the accumulator 10 is connected to the hydraulic unit 20 , and the other side is connected to the pressure sensor 13 , and the safety A test instrument mounting step (S2) of securing the accumulator 10 inside by fastening the cover 12 is performed.

The hydraulic oil in the storage tank is boosted through the motor pump 21 of the hydraulic unit 20 to supply hydraulic pressure to the accumulator 10, and the pressure sensor 13 to supply the hydraulic pressure to the accumulator 10. Measured value A measurement value generation step (S3) of outputting is performed.

At this time, since the hydraulic pressure supplied to the accumulator 10 is in the form of pulsation and vibration through the proportional control valve 22 that controls the opening and closing of the internal flow path in response to the set value, the field situation and the test environment are similar. It works.

In addition, the measured value communicates with an external PC through the DAQ module 34, and the external PC creates an abnormal signal condition by the pressure deviation of the measured value, generates an alarm for the abnormal signal, and maintains a database for the abnormal signal. It is possible to predict the lifespan of the accumulator 10 by constructing the accumulator 10 , so that the user can predict the replacement timing of the accumulator 10 .

In other words, during the normal experiment of the accumulator 10, the difference between the set value and the measured value does not differ significantly, but when the accumulator 10 has defects such as upper and lower shell breakage, screw thread defect, membrane breakage, hydraulic hose burnout, etc. The pressure as much as the set value cannot be measured, and such an accident does not happen all at once, but is accompanied by a precursor to an accident, and the pressure deviation is the difference between the graph of the hydraulic pressure obtained during a normal experiment and the graph of the hydraulic pressure that appears at the time of an accident. It can be said that the abnormal signal refers to the pressure graph that is judged as a precursor phenomenon before the pressure deviation occurs.

Then, an error checking step (S4) of comparing the hydraulic pressure measurement value of the pressure sensor 13 corresponding to the set value with the accumulator 10 endurance test standard and outputting error data is performed,

In the error checking step, the error between the set value and the measured value can be reduced by further including a PID control step (S7) of correcting the set value through the error data and obtaining the measured value with the corrected set value.

Finally, when the number of operations is not completed, the measurement value generation step (S3) is performed again, and when the number of operations is completed, the operation number check step (S5) of outputting the completion of the endurance test; The test is completed, and the data generated during the endurance test is saved in an external PC.

Although embodiments of the present invention have been described with reference to the above and the accompanying drawings, those of ordinary skill in the art to which the present invention pertains can practice the present invention in other specific forms without changing its technical spirit or essential features. You will understand that there is Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

10: Accumulator
11: Jig
12: safety cover
13: pressure sensor
14: oil leak support
20: hydraulic unit
21: motor pump
22: proportional control valve
23: protection circuit
24: chiller cooler
30: controller unit
31: touch panel
32: PLC
33: hydraulic valve amplifier
34: DAQ module

Claims (6)

In the high-pressure membrane accumulator durability test method for securing fuel supply safety of eco-friendly ships,
A set value input step (S1) of inputting a set value including one or more of the maximum/minimum value of the supply hydraulic pressure, the frequency of the flow, and the number of operations according to the specifications of the test target accumulator 10 to the touch panel 31;
The accumulator 10 is mounted in the open space of the jig 11, one side of the accumulator 10 is connected to the hydraulic unit 20, the other side is connected to the pressure sensor 13, and a safety cover 12 ) to secure the accumulator (10) inside the test device mounting step (S2);
The hydraulic oil in the storage tank is boosted through the motor pump 21 of the hydraulic unit 20 to supply hydraulic pressure to the accumulator 10, and the pressure sensor 13 to measure the hydraulic pressure supplied to the accumulator 10 a measurement value generation step of outputting a value (S3);
an error checking step (S4) of comparing the hydraulic pressure measurement value of the pressure sensor 13 corresponding to the set value with an accumulator endurance test standard and outputting error data;
Accumulator endurance test method including; . According to claim 1,
In the measurement value generation step (S3),
The hydraulic pressure supplied to the accumulator 10 is,
Accumulator durability test method, characterized in that there is a pulsation and vibration through the proportional control valve (22) that controls the opening and closing of the internal flow path in response to the set value. The method of claim 1,
After the setting value input step (S1),
Accumulator durability test method, characterized in that it further comprises a test preparation step of measuring the maximum hydraulic pressure of the hydraulic unit (20) in a no-load state without the accumulator (10), and checking the measured value corresponding to the set value . According to claim 1,
After the setting value input step (S1),
Have the measured values for the temperature, hydraulic pressure, and oil level height of the hydraulic oil of the hydraulic unit 20 and the durability test standard set by the user for the oil leakage state of the accumulator 10,
The accumulator endurance test method further comprising a protection circuit operation step (S6) of stopping the motor pump (21) when the measured value and the oil leakage state are out of the endurance test standard. According to claim 1,
In the error checking step (S4),
correcting the set value through the error data,
Accumulator endurance test method, characterized in that it further comprises a PID control step (S7) for reducing the error between the set value and the measured value. According to claim 1,
In the measurement value generation step (S3),
The measured value communicates with an external PC through the DAQ module 34,
The external PC sets the abnormal signal condition by the pressure deviation of the measured value,
Accumulator endurance test method, characterized in that the life of the accumulator (10) is predicted by further comprising a pressure analysis step of generating an alarm for the abnormal signal.

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