Disclosure of Invention
The invention aims to provide a fracturing system pressure test control method, which can improve the safety of pressure test operation under a high-pressure working condition.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows: a fracturing system pressure test control method comprises the following steps:
s1, closing a valve of a discharge pipeline of the fracturing device;
s2, the controller outputs a section of pulse signal to drive a motor of the fracturing device to rotate, so that the pressure of the discharge pipeline is increased, and the pressure sensor of the discharge pipeline outputs a pressure signal;
s3, the controller receives the pressure signal, compares the pressure signal with a preset pressure value, maintains the pressure if the pressure signal reaches the preset pressure value, outputs a section of same pulse signal again if the pressure signal does not reach the preset pressure value, and drives a motor of the fracturing device to rotate to enable the pressure of the discharge pipeline to rise until the preset pressure value is reached;
the pressure test operation of the fracturing system is realized through the steps.
In the preferred scheme, the pulse signal is a pulse signal within a preset time, and the duration is 0.1-3 seconds.
In a preferred embodiment, the method further comprises the following steps:
s4, maintaining the pressure for a period of time, reading a current pressure signal output by the pressure sensor, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, completing the pressure test;
if the current pressure value exceeds the preset range interval of the preset pressure value, outputting a fault alarm;
the pressure test operation of the fracturing system is realized through the steps.
In a preferred embodiment, the method further comprises the following steps:
s5, connecting the discharge pipeline of each fracturing device with a trunk pipeline through a branch pipeline, connecting the trunk pipeline with a bus pipeline, arranging a branch valve and a branch pressure sensor on the branch pipeline, arranging a trunk valve and a trunk pressure sensor on the trunk pipeline, and arranging a bus valve and a bus pressure sensor on the bus pipeline;
closing branch valves, and carrying out pressure test operation on each fracturing device;
and completing the pressure test operation of each branch line, and then sequentially completing the pressure test operation of the trunk line and the bus line.
In a preferred scheme, the pressure test operation of each branch line is synchronously performed.
In a preferred embodiment, the method further comprises the following steps:
s6, disconnecting the fracturing devices with faults, closing the main line valves and opening the branch line valves corresponding to the fracturing devices;
s7, the controller of any one or more fracturing devices outputs a section of pulse signal to drive the motor of the fracturing device to rotate, so that the pressure of the discharge pipeline is increased, and the main line pressure sensor outputs a pressure signal;
s8, the controller receives the pressure signal, compares the pressure signal with a preset pressure value, maintains the pressure if the pressure signal reaches the preset pressure value, outputs a section of same pulse signal again if the pressure signal does not reach the preset pressure value, and drives a motor of the fracturing device to rotate to enable the pressure of the discharge pipeline to rise until the preset pressure value is reached;
s9, maintaining the pressure for a period of time, reading a current pressure signal output by the pressure sensor, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, finishing the trunk line pressure test;
if the current pressure value exceeds the preset range of the pressure value, outputting a fault alarm of the main pipeline;
s10, closing the bus valve and opening the main valve;
s11, outputting a section of pulse signal by a controller of any one or more fracturing devices, driving a motor of the fracturing device to rotate, increasing the pressure of a discharge pipeline, and outputting a pressure signal by a bus pressure sensor;
s12, the controller receives the pressure signal, compares the pressure signal with a preset pressure value, maintains the pressure if the pressure signal reaches the preset pressure value, outputs a section of same pulse signal again if the pressure signal does not reach the preset pressure value, drives a motor of the fracturing device to rotate, enables the pressure of the discharge pipeline to rise until the pressure reaches the preset pressure value, and maintains the pressure;
s13, maintaining the pressure for a period of time, reading a current pressure signal output by the pressure sensor, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, completing bus pressure test;
if the current pressure value exceeds the preset range of the pressure value, outputting a fault alarm of the bus pipeline;
the pressure test operation of the fracturing system with a plurality of fracturing devices is completed through the steps.
The preset pressure value is 145-175 MPa.
Under the condition that one set of fracturing device confirms to be reliable, obtaining a pressure increase curve by using a fixed pulse signal, and correcting the pressure increase curve by using a plurality of fracturing devices confirming to be reliable;
and recording a pressure increase curve of the pressure test operation of the subsequent equipment, and comparing the pressure increase curve with a standard pressure increase curve to quickly confirm whether the current equipment for pressure test has faults or hidden fault hazards.
According to the fracturing system pressure test control method provided by the invention, the safety of pressure test operation can be greatly improved, the pressure test efficiency is improved, and in the preferred scheme, the scheme of grouping and calibrating the pressure increase curve is adopted, so that the fault point can be quickly positioned.
Detailed Description
The fracturing device 1 is structurally shown in fig. 2, two output shafts of a double-extension-shaft motor 101 are connected with a multi-cylinder pump 103 through a clutch 102, the multi-cylinder pump 103 adopts a plurality of piston pumps driven by a crankshaft, the position of a pump head is connected with an inlet pipeline through a liquid inlet one-way valve, the inlet pipeline is connected with a sand mixing device, the position of the pump head is connected with a discharge pipeline 104 through a liquid discharge one-way valve, and a valve and a pressure sensor are arranged on the discharge pipeline 104.
Example 1:
as shown in fig. 3, a method for controlling pressure test of a fracturing system includes the following steps:
s1, closing the valve of the discharge line 104 of the fracturing device 1;
s2, the controller outputs a section of pulse signal to drive a motor of the fracturing device 1 to rotate, so that the pressure of the discharge pipeline 104 is increased, and the pressure sensor of the discharge pipeline 104 outputs a pressure signal; preferably, the pulse signal is a pulse signal within a preset time, and the duration is 0.1-2 seconds. The pulse signal is used as an instruction signal of the motor frequency converter, and the motor frequency converter controls the motor to rotate.
S3, the controller receives the pressure signal, compares the pressure signal with a preset pressure value, maintains the pressure if the pressure signal reaches the preset pressure value, outputs a section of same pulse signal again if the pressure signal does not reach the preset pressure value, and drives the motor of the fracturing device 1 to rotate to enable the pressure of the discharge pipeline 104 to rise until the preset pressure value is reached; in a preferable scheme, the preset pressure value is 145-175 MPa. 175MPa is used in this case.
S4, maintaining the pressure for a period of time, reading a current pressure signal output by the pressure sensor, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, completing the pressure test;
if the current pressure value exceeds the preset range interval of the preset pressure value, outputting a fault alarm;
the pressure test operation of the fracturing system is realized through the steps. By adopting the scheme of short-time pulse and pressure feedback implementation, the invention ensures the safety and reliability of the pressure test process of the fracturing device. The probability of personnel and equipment loss is reduced to the minimum.
It is further preferred that in case a set of fracturing units 1 confirms reliability, the pressure increase curve is obtained by the method described above with a fixed pulse signal, as shown in fig. 4. And the pressure increase curves of a plurality of confirmed reliable fracturing devices 1 are corrected, the pressure increase curves of the pressure test operation of the subsequent fracturing devices 1 are recorded and compared with the standard pressure increase curves, and therefore whether faults or hidden troubles of the current fracturing devices 1 for pressure test exist can be quickly confirmed.
Example 2:
on the basis of the embodiment 1, the preferable scheme further comprises the following steps:
s5, as shown in fig. 1, the discharge pipe 104 of each fracturing device 1 is connected to the trunk pipe 3 through the branch pipe 2, the trunk pipe 3 is connected to the bus pipe 4, the branch pipe 2 is provided with the branch valve 21 and the branch pressure sensor 22, the trunk pipe 3 is provided with the trunk valve 31 and the trunk pressure sensor 32, and the bus pipe 4 is provided with the bus valve 41 and the bus pressure sensor 42; preferably, each trunk line 3 is connected to a buffer tank 5, and the buffer tank 5 is connected to the bus line 4. The sand mixing device is characterized in that the sand tanks are connected with the sand mixing device, the liquid tanks are connected with the sand mixing device, and the sand mixing device is one or more than one sand tank. The sand mulling device is connected with the inlet management of each fracturing device 1 through a low-pressure pipeline.
Closing the branch valves 21 and performing pressure test operation on each fracturing device 1;
and completing the pressure test operation of each branch line, and then sequentially completing the pressure test operation of the trunk line and the bus line.
In a preferred scheme, the pressure test operation of each branch line is synchronously performed.
S6, disconnecting the fracturing device 1 with the fault, closing the main line valve 31, opening the branch line valves 21 corresponding to the fracturing devices 1, and closing the main line valve 31;
s7, the controller of any one or more fracturing devices 1 outputs a section of pulse signal to drive the motors of the fracturing devices 1 to rotate, so that the pressure of the discharge pipeline 104 is increased, and the main line pressure sensor 32 outputs a pressure signal;
s8, the controller receives the pressure signal, compares the pressure signal with a preset pressure value, maintains the pressure if the pressure signal reaches the preset pressure value, outputs a section of same pulse signal again if the pressure signal does not reach the preset pressure value, and drives the motor of the fracturing device 1 to rotate to enable the pressure of the discharge pipeline 104 to rise until the preset pressure value is reached;
s9, maintaining the pressure for a period of time, reading a current pressure signal output by the pressure sensor, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, finishing the trunk line pressure test;
if the current pressure value exceeds the preset range of the pressure value, outputting a fault alarm of the main pipeline 3;
s10, closing the bus valve 41 and opening the main valve 31;
s11, the controller of any one or more fracturing devices 1 outputs a section of pulse signal to drive the motors of the fracturing devices 1 to rotate, so that the pressure of the discharge pipeline 104 is increased, and the bus pressure sensor 42 outputs a pressure signal;
s12, the controller receives the pressure signal, compares the pressure signal with a preset pressure value, maintains the pressure if the pressure signal reaches the preset pressure value, outputs a section of same pulse signal again if the pressure signal does not reach the preset pressure value, drives the motor of the fracturing device 1 to rotate, enables the pressure of the discharge pipeline 104 to rise until the pressure reaches the preset pressure value, and maintains the pressure;
s13, maintaining the pressure for a period of time, reading a current pressure signal output by the pressure sensor, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, completing bus pressure test;
if the current pressure value exceeds the preset range of the pressure value, outputting a fault alarm of the bus pipeline 4;
the pressure test operation of the fracturing system having a plurality of fracturing devices 1 is completed through the above steps.
Example 3:
in another optional scheme, a method for controlling pressure test of a fracturing system comprises the following steps:
s01, connecting the discharge pipe 104 of each fracturing device 1 with the trunk pipe 3 through the branch pipe 2, connecting the trunk pipe 3 with the bus pipe 4, arranging the branch valve 21 and the branch pressure sensor 22 on the branch pipe 2, arranging the trunk valve 31 and the trunk pressure sensor 32 on the trunk pipe 3, and arranging the bus valve 41 and the bus pressure sensor 42 on the bus pipe 4;
closing the bus valve 41, and giving a signal by the main controller to enable a part of branch controllers to control the output pressure of the fracturing device 1;
the bus pressure sensor 42 outputs a pressure signal, and the main controller receives the pressure signal and compares the pressure signal with a preset pressure value;
s02, grouping again, the main controller gives out signals to make a part of branch controllers output pressure;
the bus pressure sensor 42 outputs a pressure signal, and the main controller receives the pressure signal and compares the pressure signal with a preset pressure value;
s03, regrouping, wherein the main controller gives signals to make part of branch controllers output pressure;
s04, sequentially executing the steps S02-S03 to enable all the fracturing devices controlled by the branch controllers to participate in pressure output;
s05, when the pressure fed back by the bus pressure sensor 42 reaches a set value, maintaining the pressure;
after the pressure is maintained for a period of time, reading a current pressure signal output by the bus pressure sensor 42, comparing the current pressure signal with a preset pressure value, and if the current pressure value is within a set range of the preset pressure value, completing the pressure test;
if the current pressure value exceeds the preset range interval of the preset pressure value, outputting a fault alarm, and starting a fault positioning step;
the rapid pressure test operation of the fracturing system is realized through the steps. In the pressure test operation process, the fault point can also be quickly positioned.
In the preferred scheme as shown in fig. 4, in the process of pressure test operation, grouping conditions and pressure values after each pressure test operation are recorded to obtain an actual pressure increase curve;
and comparing the actual pressure increase curve with a preset pressure increase curve, and quickly positioning the fault position according to the record of the difference position and the grouping condition.
In a preferred scheme, after each grouping, the number of the fracturing devices 1 outputting pressure is kept consistent, and the pulse signals output each time are kept consistent. The grouping method in this example adopts a round-robin grouping scheme, for example, 10 sets of fracturing devices 1 are grouped into numbers 01-10, and 2 sets are used for pressure testing, wherein the first set is numbers 01 and 02, the second set is numbers 02 and 03, and so on. Each set of fracturing device 1 is ensured to participate in at least one pressure test output, preferably more than 2 pressure test outputs.
In the preferred scheme, if the actual pressure increase curve and the preset pressure increase curve have differences at the output position of each pressure test, the fault is positioned in the bus pipeline 4.
In the preferred scheme, the corresponding grouping condition records are inquired according to the difference points, and the failure probability of more fracturing devices 1 in the grouping is higher. For example, when the positions of pressure test outputs involving the fracturing device No. 03 are different every time, the fault is positioned in the fracturing device No. 03 and the branch pipeline 2 connected with the fracturing device No. 03, the fault point can be quickly found by independently testing the fracturing device No. 03, after the fault point is found, equipment of the fault point is independently disconnected, for example, one or two clutches 102 in the fracturing device No. 1 are disconnected, and the steps are carried out again until all the fault points are eliminated. When the number of the fracturing devices 1 is larger than the number of the members grouped at each time, and each set of the fracturing device 1 can be ensured to participate in at least one pressure test output, the obtained actual pressure increase curve is irrelevant to the number of the fracturing devices 1.
In a preferred scheme, the preset pressure increase curve is obtained by adopting a fault-free fracturing system according to the same grouping number and output pulse signal measurement. In a preferable scheme, the preset pressure value is 145-175 MPa.
The above-described embodiments are merely preferred embodiments of the present invention, and should not be construed as limiting the present invention, and the scope of the present invention is defined by the claims, and equivalents including technical features described in the claims. I.e., equivalent alterations and modifications within the scope hereof, are also intended to be within the scope of the invention. For the sake of brevity, all the combinations of the embodiments are not exemplified, and therefore, the technical features of the embodiments can be combined with each other to generate more technical solutions without conflict.