Disclosure of Invention
One of the purposes of the invention is to provide a valve internal leakage rate evaluation device which can realize online monitoring on valve internal leakage.
The utility model provides a leak leakage rate evaluation device in valve, its includes gas holder, air compressor machine, valve two, flowmeter and test valve, the air compressor machine be used for carrying out the punching press to the gas holder, the gas holder with the flowmeter between set gradually the pipeline of connecting on valve two and test valve, test valve on install acoustic sensor, acoustic sensor be connected with acoustics collection equipment through the data line.
As a preferable scheme of the present invention, a pressure gauge is installed on the air storage tank, and when the air compressor presses the air storage tank, the pressure gauge is used to monitor a pressure value.
In another preferred embodiment of the present invention, the test valve is a gate valve or a ball valve.
The ball valve is a floating ball valve, a fixed ball valve, a wafer ball valve, a three-way ball valve or a V-shaped ball valve.
The gate valve is a rising stem gate valve or a non-rising stem gate valve.
According to specifications, the ball valve comprises a ball valve specification of 101 and a ball valve specification of 104, and the ball valve specification of 101 comprises DN100, DN15, DN20, DN25, DN32, DN40, DN50, DN65 and DN 80.
The second objective of the present invention is to provide a method for evaluating the leak rate of valve inner leakage, which can determine the leak rate of valve inner leakage.
A valve internal leakage rate evaluation grade method adopts the valve internal leakage rate evaluation device, acoustic parameters AErms are measured through an acoustic sensor, internal leakage is measured through a flowmeter, a pressure gauge connected to a gas storage tank is used for providing test pressure parameters, and function fitting is carried out according to an internal leakage flow Q-AErms curve so as to obtain a Q-AErms fitting function; and then, according to the Q-AErms fitting function, combining with a flow grade division standard to obtain the AErms evaluation standard for testing the internal leakage of the valve.
More preferably, the above AErms evaluation criteria are:
further preferably, the Q-AErms fitting function is as shown in equation (1):
lg Qg=3.302*lg AErms-4.642 (1);
in the formula: qgIs the gas flow rate in the standard state, m3/h;
AErms is the acoustic parameter measured by the acoustic sensor.
Further, when X < Fγ·XτWhen is, Qg=0.28(X)1/2Yp1Kv
When X is more than or equal to Fγ·XτWhen is, Qg=0.19(Xτ)1/2p1Kv
Wherein: qg- -gas flow rate in standard state, m3/h;
Kv-nominal flow coefficient, dimensionless;
x- - -ratio of differential pressure to absolute inlet pressure (Δ p/p)1) No dimension;
y-expansion systemNumber, Y ═ 1-X/(3X)τ) (when X > F)γ·XτWhen Y is 0.667), no dimension exists;
p1absolute pressure before valve, kPa;
Xτ-the differential pressure ratio coefficient, dimensionless, of a control valve without an attached pipe under choked flow conditions;
Fγcoefficient of specific heat ratio, F of air in a specified temperature rangeγ1, dimensionless.
Further preferably, K is as defined abovevCalculated according to the formulas (2) and (3):
in formula (2): cv- -flow coefficient, Usgal/min;
k is the flow resistance coefficient and is dimensionless;
d- - -valve drift diameter, inch;
Kv=Cv/1.156 (3);
further preferably, the values of the parameters in the formulas (2) and (3) refer to GBT4213-2008 pneumatic control valves and GBT17214.2-2005 industrial process control valves.
Further preferably, when the test valve is a gate valve, the flow resistance K-nominal diameter/mm function is:
when the test valve is a ball valve, the flow resistance coefficient K-nominal diameter/mm function is:
compared with the prior art, the invention has the following beneficial technical effects:
(1) acoustic parameters are obtained through equipment such as an acoustic sensor, and the acoustic emission detection means can effectively perform online detection on the internal leakage of the valve, so that economic loss caused by shutdown is avoided;
(2) the method for evaluating the grade of the leakage rate of the internal leakage of the valve can grade the severity of the internal leakage, and fills the gap that no clear standard exists in the evaluation of the leakage rate of the internal leakage of the valve at present;
(3) the testing valve can be a ball valve or a gate valve, and the type and the caliber of the valve are not limited by the method;
(4) the invention can judge the leakage grade in the valve on line through the acoustic parameters without shutdown. The invention can effectively perform online detection of the internal leakage of the valve by using an acoustic emission detection means, thereby avoiding economic loss caused by shutdown; at present, no clear standard exists for evaluating the size of the leakage rate of the internal leakage of the valve on site, and the evaluation method for the grade of the leakage rate of the internal leakage of the valve can grade the severity of the internal leakage.
(5) The device and the method are safe to use, convenient to implement and capable of being popularized and used in petrochemical enterprises.
Detailed Description
The invention provides a device and a method for evaluating the leakage rate of valve internal leakage, and the invention is described in detail with reference to specific embodiments in order to make the advantages and technical scheme of the invention clearer and clearer.
Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.
Spatially relative terms, such as "below," "lower," "upper," "above," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the object in use or operation in addition to the orientation depicted in the figures. For example, if the items in the figures are turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the elements or features. Thus, the exemplary term "below" can encompass both an orientation of below and above. Other orientations of the components are possible (rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.
The term "air compressor" as used herein refers to an air compressor.
As shown in fig. 1, the valve internal leakage rate evaluation device comprises an air storage tank, an air compressor, a first valve, a second valve, a flowmeter, a test valve and an acoustic sensor, wherein the air compressor is connected with the air storage tank and used for stamping the air storage tank, a pressure gauge is mounted on the air storage tank, when the air compressor stamps the air storage tank, the pressure value is monitored through the pressure gauge, when the index of the pressure gauge reaches the test pressure, the air compressor is stopped, the first valve is closed, and the test is prepared.
The gas storage tank is a device specially used for storing gas, plays a role in stabilizing the pressure of the system, and can be divided into a high-pressure gas storage tank, a low-pressure gas storage tank and a normal-pressure gas storage tank according to different bearing pressures of the gas storage tank. The gas storage tank can be divided into a carbon steel gas storage tank, a low alloy steel gas storage tank and a stainless steel gas storage tank according to different materials of the gas storage tank. In particular, the present invention allows for the conditions that meet the gas phase conditions of different petrochemical scenarios, and therefore prefers a high pressure gas tank that can meet a wide pressure range.
The air compressor is an air compressor, which is a device for compressing air, and has a structure similar to a water pump, and those skilled in the art can realize the air compressor by using the prior art, and the detailed description is omitted here.
The acoustic sensor described above functions by converting acoustic pressure waves into vibrations of a mechanical element and qualitatively detecting these vibrations by changes in the piezoelectric, resistivity, permeability or capacitance.
And a second valve and a test valve are sequentially arranged on a pipeline connected between the gas storage tank and the flowmeter, an acoustic sensor is installed on the test valve, and the acoustic sensor is connected with acoustic acquisition equipment through a data line.
The flowmeter is arranged behind the test valve, the valve II is opened, different flow tests are carried out by adjusting the opening of the test valve, acoustic signals are collected after the test is started, and parameter information such as pressure values, gas flow values and the like is recorded.
The specific structure of the acoustic sensor and the monitoring method thereof are not described in detail, and can be realized by referring to the prior art.
The shape, specification and type of the test valve are not limited, and the test valve is a gate valve or a ball valve. Specifically, the ball valve may be classified into a floating ball valve, a fixed ball valve, a wafer ball valve, a three-way ball valve or a V-shaped ball valve, a stainless steel ball valve, etc. according to its kind.
Specifically, the gate valve may be a rising stem gate valve or a non-rising stem gate valve.
The stainless steel ball valve has the specification such as a 101 ball valve, a 104 ball valve, a 201 ball valve, a 206 flange ball valve, a 216 ball valve and the like. Such as for each of the specifications of the ball valve:
101 ball valves comprise DN100, DN15, DN20, DN25, DN32, DN40, DN50, DN65 and DN 80;
104 the ball valve specifications include: DN10, DN100, DN15, DN20, DN25, DN32, DN40, DN50, DN65, DN8, DN 80;
201 ball valve specification: DN10, DN100, DN15, DN20, DN25, DN32, DN40, DN50, DN65, DN8, DN 80;
specification of 206 flange ball valve: DN100, DN25, DN32, DN40, DN50, DN65, DN 80;
216 ball valve specification: DN15, DN15, DN20, DN20, DN25, DN25, DN32, DN32, DN40, DN40, DN50, and the like.
The types and specifications of the ball valve or the gate valve are not described in detail, and those skilled in the art can reasonably select the type and specification according to actual needs.
The evaluation method of the present invention will be described in detail with reference to specific examples.
Example 1:
a valve internal leakage rate evaluation grade method is characterized in that a valve internal leakage rate evaluation device comprises an air storage tank, an air compressor, a second valve, a flowmeter and a test valve, wherein the air compressor is used for stamping the air storage tank, the second valve and the test valve are sequentially arranged on a pipeline connected between the air storage tank and the flowmeter, an acoustic sensor is mounted on the test valve, and the acoustic sensor is connected with acoustic acquisition equipment through a data line; the air storage tank is provided with a pressure gauge, and when the air compressor punches the air storage tank, the pressure value is monitored through the pressure gauge.
The method for evaluating the grade of the internal leakage rate of the valve specifically comprises the following steps:
firstly, measuring an acoustic parameter AErms through an acoustic sensor, and measuring internal leakage through a flowmeter;
secondly, providing a test pressure parameter through a pressure gauge connected to a gas storage tank, and performing function fitting according to an internal leakage flow Q-AErms curve to further obtain a Q-AErms fitting function;
and thirdly, combining flow grade division standards according to a Q-AErms fitting function to obtain the AErms evaluation standard for testing the internal leakage of the valve.
Example 2:
the valve internal leakage rate evaluation device comprises a gas storage tank, an air compressor, a second valve, a flowmeter and a test valve, wherein the air compressor is used for stamping the gas storage tank, the second valve and the test valve are sequentially arranged on a pipeline connected between the gas storage tank and the flowmeter, an acoustic sensor is mounted on the test valve, and the acoustic sensor is connected with acoustic acquisition equipment through a data line; the air storage tank is provided with a pressure gauge, and when the air compressor punches the air storage tank, the pressure value is monitored through the pressure gauge.
The formula in the calculation standard for the rated capacity of the valve according to GBT4213-2008 pneumatic control valve and GBT17214.2-2005 industrial process control valve part 5-1 is shown in the following table.
TABLE 1 calculation formula for rated capacity of valve
Wherein Q isg- -gas flow rate in standard state, m3/h;
Kv-nominal flow coefficient, dimensionless;
x- - -ratio of differential pressure to absolute inlet pressure (Δ p/p)1) No dimension;
y- - -expansion coefficient, Y1-X/(3X)τ) (when X > F)γ·XτWhen Y is 0.667), no dimension exists;
p1absolute pressure before valve, kPa;
Xτ-the differential pressure ratio coefficient, dimensionless, of a control valve without an attached pipe under choked flow conditions;
Fγcoefficient of specific heat ratio, F of air in a specified temperature rangeγ1, dimensionless;
calculating the rated capacity of the valve according to the formula, wherein the rated flow coefficient KvThe calculation is carried out according to the following formula, wherein the values of all parameters in the formula refer to GBT4213-2008 pneumatic regulating valve and GBT17214.2-2005 industrial process control valve.
Cv- -flow coefficient, Usgal/min;
k is the flow resistance coefficient and is dimensionless;
d- - -valve drift diameter, inch;
Kv=Cv/1.156
the flow coefficients K for the different size and type valves are shown in table 2 below.
TABLE 2 flow resistance coefficient K of different size and type valves
According to the data, the flow resistance coefficient of the ball valve is constant 0.1, while the flow resistance coefficients of the gate valve and the stop valve are not fixed, and the nominal diameter and the flow resistance coefficient of the gate valve and the stop valve are fitted to obtain a flow resistance coefficient K-nominal diameter function, as shown in Table 3.
TABLE 3 flow resistance coefficient K-nominal diameter (mm) function of gate valve and stop valve
The calculation formula of the rated capacity of the stop valve is as follows:
(Usgal/min)
Kv=101.9÷1.156=88.12m3/h
due to the fact that
Thus using the formula
Calculating Q
g。
Qg=18389L/min
According to the algorithm, the rated capacity of the valve is calculated respectively. According to the provisions of GBT4213-2008 pneumatic control valve and GBT17214.2-2005 Industrial Process control valve, Qg×10-4For minor leakage, Qg×10-3For small leakage, Qg×5×10-3In the case of a medium leak,Qg×10-2is a large leak.
Example 3:
the valve internal leakage rate evaluation device comprises a gas storage tank, an air compressor, a second valve, a flowmeter and a test valve, wherein the air compressor is used for stamping the gas storage tank, the second valve and the test valve are sequentially arranged on a pipeline connected between the gas storage tank and the flowmeter, an acoustic sensor is mounted on the test valve, and the acoustic sensor is connected with acoustic acquisition equipment through a data line; the air storage tank is provided with a pressure gauge, and when the air compressor punches the air storage tank, the pressure value is monitored through the pressure gauge.
On the basis of example 2, the test valve is a gate valve under 0.1 MPa.
The pressurization is performed using a compressor. The testing pressure is 0.1MPa, the testing adopts a DN65 gate valve, the leakage flow is adjusted by adjusting the opening of the gate valve, the testing is carried out by a flowmeter, and the leakage rate is tested from 6L/min to 120L/min by a difference value of 6L/min. And acquiring acoustic emission signal data under various working conditions to provide data support for the diagnosis method. And detecting by adopting acoustic emission acquisition equipment, wherein a 30kHz resonance sensor is selected as the sensor.
And performing function fitting according to an internal leakage flow Q-AErms curve to obtain a Q-AErms fitting function.
The gate valve Q-AErms function fitting coefficient R-square of DN65 is 0.8404, accords with the application requirement of engineering R-square >0.9, and the fitting function is lg Q-3.302 lg A Erms-4.642.
And (4) obtaining DN65 gate valve internal leakage AErms evaluation standard by combining the flow grade division standard according to a Q-AErms fitting function, wherein the evaluation standard is shown in a table 4.
TABLE 4 DN65 ball valve internal leakage AErms evaluation criteria
As shown in fig. 2, the AErms evaluation criteria is scaled down by 5% according to engineering criteria, and if the in-valve leak signal AErms is above the micro-leak criterion 95%, the valve is evaluated as a small leak, and if the in-valve leak AErms is below the micro-leak criterion 95%, the valve is evaluated as a small leak.
In conclusion, the method for evaluating the grade of the leakage rate of the valve inner leakage provided by the invention comprises various valve types and valve calibers and meets the measurement requirements of different leakage amounts. The evaluation device for the internal leakage rate of the valve can judge the internal leakage grade of the valve on line through the acoustic parameters without shutdown, and can be popularized and used in petrochemical enterprises.
The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto.
Although terms such as air reservoir, air compressor, flow meter, test valve, etc. are used more often herein, the possibility of using other terms is not excluded, and these terms are used only for the purpose of more conveniently describing and explaining the essence of the present invention; they are to be construed as being without limitation to any additional limitations that may be imposed by the spirit of the present invention.
It is further understood that the specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.