CN204314001U - Pipe flange stress monitoring system under Moments effect - Google Patents

Abstract

The utility model discloses a pipe flange stress monitoring system under the action of an external bending moment, which comprises a left pipe, a right pipe, and a flange connecting the left pipe and the right pipe. The flange is sealed by a gasket, and the left pipe , the right pipe and the flange form a flange cavity to be tested; the left pipeline is connected to the pump through a valve, and the right pipeline is welded to a blind plate; a temperature sensor and a pressure sensor are arranged in the flange cavity to be tested; the system also includes an external A bending moment loading mechanism and a stress testing mechanism, the stress testing mechanism includes a strain gauge, and the strain gauge is connected with the strain gauge and the computer through a cable. The utility model is applied to the flange under the action of the external bending moment, and can monitor the distribution of the stress on the outer wall of the flange in real time; and the stress measurement is accurate, and has strong guiding significance for scientific research and engineering.

Description

Pipeline flange stress monitoring system under external bending moment

technical field

The utility model relates to a flange testing system, in particular to a pipeline flange stress monitoring system under the action of an external bending moment.

Background technique

Flange connection is a commonly used connection method in petrochemical equipment. Because of its advantages of easy disassembly and installation, it is widely used in pressure vessels and pipelines in petrochemical, nuclear power, metallurgy, pharmaceutical and other industries. With the increasingly prominent contradiction between economic development and energy supply, and the rapid development of oil refining and chemical technology, pipeline flanges are widely used in various refining and chemical equipment. During production and construction, the flange may undergo changes such as deflection, warping, creep, crack growth, etc., and the stress of each part of the flange changes complicatedly; when there is an external bending moment, the stress characteristics of each part of the flange will also change greatly. Changes, deflection, warping, cracks may exacerbate leaks. Flange leakage is one of the main causes of major accidents in petrochemical and other enterprises. Therefore, it is necessary for us to design a pipe flange stress monitoring system under the action of external bending moment to monitor the complex stress on the flange to ensure the safety of the pipe connection.

Utility model content

The purpose of this utility model is to provide a pipeline flange stress monitoring system under the action of external bending moment. The test system is applied to the flange under the action of external bending moment to monitor the distribution of stress on the outer wall of the flange in real time and can accurately monitor the flange. Stress, to ensure the smooth progress of production and construction.

The utility model is achieved in the following way: a stress monitoring system for pipe flanges under the action of external bending moments, which includes left pipes, right pipes, and flanges connecting the left pipes and right pipes, and the flanges are sealed with gaskets , the left pipe, the right pipe, and the flange form a flange cavity to be tested;

The left pipeline is connected to the pump through a valve, and the right pipeline is welded to a blind plate; a temperature sensor and a pressure sensor are arranged in the cavity of the flange to be measured;

The system also includes an external bending moment loading mechanism and a stress testing mechanism. The external bending moment loading mechanism includes a hydraulic loading device, and the hydraulic loading device applies force to the left and right pipelines, and cooperates with the support. An external torque is formed on the pipeline at the location, and the magnitude of the torque can be adjusted freely. The stress testing mechanism includes a strain gauge, and the strain gauge is connected with the strain gauge and the computer through a cable.

The strain gauges are distributed on the left pipe cylinder section, the right pipe cylinder section, the flange taper neck section and the outer wall of the flange plate, and are uniformly distributed along the circumferential direction.

In the pipe flange stress monitoring system under the action of external bending moment, a pump is installed at the left end of the cavity to be tested in the flange, and a valve is installed on the output pipeline of the pump. The output pipeline is directly connected to the left pipeline, and the medium It is transported to the cavity of the flange to be tested, and a pressure sensor and a temperature sensor are set in the cavity of the flange to be tested. The temperature sensor monitors the temperature of the medium in the cavity of the flange to be tested. The pressure in the cavity; the support bracket (support) is set under the pipe, and the exhaust valve is set above the pipe; the flange is connected by bolts and sealed with gaskets.

The external bending moment loading mechanism is mainly composed of a liquid crystal control panel, a hydraulic loading device, a loading bracket and a loading arm; the hydraulic loading device can be controlled by the liquid crystal control panel, and a reasonable loading can be performed according to the needs of the test, that is, it can provide Load from zero to any desired load value within the range. The loading bracket is welded as a whole with the extension rod of the hydraulic loading device. The hydraulic loading device can provide a force of any size within the range. The loading bracket is provided with a loading arm. The loading arm can move left and right on the loading bracket and cooperate with the support under the pipeline to provide different types and sizes of bending (The loading arm can move left and right on the bending moment loading bracket to the inner and outer sides of the support to load different types of bending moments.). The loading arm is in contact with the left pipe and the right pipe.

The flange stress testing mechanism mainly includes strain gauges and strain gauges, and the strain gauges are evenly distributed on the pipe cylinder section, the flange taper neck section and the outer wall of the flange plate, and are evenly distributed along the circumferential direction; the strain gauges The electrical signal changes are transmitted to the strain gauge and the computer by the cable.

The high temperature pipeline flange test system under the action of external bending moment is mainly composed of the pipeline flange connection mechanism (the pipeline flange connection mechanism is composed of pumps, pipes, flanges, blind plates, etc.), external bending moment loading mechanism and stress testing mechanism. The pump creates a high-pressure environment in the cavity of the flange to be tested, and the temperature and pressure sensors measure the temperature and pressure of the cavity to be tested in the flange. The external bending moment loading mechanism exerts any force within the range of the hydraulic loading device on the pipes at both ends of the flange (left pipe, right pipe), and the force is combined with the support below the pipe to form a bending moment. The size of the moment.

The utility model uses a pump or an air compressor to provide a high-pressure environment for the pipeline flange connection mechanism, and can perform tests under multiple sets of pressures to ensure accurate test results. The utility model is suitable for liquid medium and gas medium. The utility model can accurately measure the stress on the pipe cylinder section, the cone neck section and the outer wall of the flange plate connected by the flange under the high-pressure condition and bear the external bending moment, and monitor the stress level on the flange under different pressure conditions in real time. The utility model is applied to the flange under the action of the external bending moment, and can monitor the distribution of the stress on the outer wall of the flange in real time, and judge whether there is an internal crack and the expansion of the crack. The utility model has accurate stress measurement and has strong guiding significance for both scientific research and engineering.

Description of drawings

Figure 1 is a schematic structural diagram of the stress monitoring system for the pipe flange under the action of the external bending moment.

Fig. 2 is an enlarged view of D in Fig. 1 .

In the figure: 1-pump, 2-valve, 3-left pipe, 4-line, 5-bolt, 6-gasket, 7-flange, 8-exhaust valve, 9-blind plate, 10-bottom flow port Valve, 11-support, 12-temperature sensor, 13-pressure sensor, 14-computer, 15-strain gauge, 16-strain gauge, 17-LCD control panel, 18-loading bracket, 19-hydraulic loading device, 20- Loading arm, 21-right pipe.

Detailed ways

Below in conjunction with accompanying drawing, the utility model is described further.

As shown in Figure 1 and Figure 2, a pipeline flange stress monitoring system under the action of external bending moment, it includes a left pipeline 3, a right pipeline 21, and a flange 7 connecting the left pipeline 3 and the right pipeline 21, the method The flange 7 is connected by the bolt 5 and sealed with the gasket 6. The left pipe 3, the right pipe 21, and the flange 7 form a flange cavity to be tested. The right pipe 21 is provided with an underflow valve 10 and an exhaust gas valve 8;

The left pipeline 3 is connected to the pump 1 through the valve 2, and the right pipeline 21 is welded to the blind plate 9; a temperature sensor 12 and a pressure sensor 13 are arranged in the cavity of the flange to be measured, and the temperature sensor 12 monitors the flange The temperature of the medium in the cavity to be measured, the pressure sensor 13 measures the pressure in the cavity of the flange to be measured;

The system also includes an external bending moment loading mechanism and a stress testing mechanism, the external bending moment loading mechanism includes a hydraulic loading device 19 controlled by a liquid crystal control panel 17, and the extension rod of the hydraulic loading device 19 is connected to the loading bracket 18 As a whole, the loading bracket 18 is provided with a loading arm 20, the hydraulic loading device 19 can provide a force of any size in the range, the loading arm 20 is in contact with the left pipeline 3 and the right pipeline 21, and the loading arm 20 can Move left and right on the loading bracket 18, and cooperate with the support 11 under the pipeline to provide different types and different sizes of bending moments; the stress testing mechanism includes strain gauges 16, computers 14 and strain gauges 15, and the strain gauges 16 are as follows: Fig. 2 is evenly distributed on the left pipe cylinder section, the right pipe cylinder section, the flange taper neck section and the outer wall of the flange plate, and is evenly distributed along the circumference, and the strain gauge 16 is connected to the strain gauge 15 through the cable 4 Connect with computer 14.

In order to ensure the accuracy of measurement, a support 11 is provided under the left pipe 3 and the right pipe 21 .

The loading arm 20 can move left and right on the loading bracket 18 to the inside and outside of the support 11 to load different types of bending moments. The loading arm 20 can be symmetrical or asymmetrical to provide different types of bending moments.

The pump 1 is used to transport the medium (liquid or gas) into the cavity of the flange to be tested, forming a high-pressure environment in the cavity of the flange to be tested, and an exhaust valve 8 is arranged on the pipeline of the cavity to be tested in the flange , used for exhausting when the medium is filled into the cavity of the flange to be tested; a temperature sensor 12 and a pressure sensor 13 are arranged in the cavity of the flange to be tested to monitor the temperature and pressure of the medium in the cavity of the flange to be tested in real time . Blind plate 9 is welded on right pipeline 21 ends, and its sealing effect is good.

A hydraulic loading device 19 is fixed above the pipe in the cavity of the flange to be tested. The hydraulic loading device 19 applies a bending moment to the pipes (left pipe, right pipe) at both ends of the flange through the loading bracket 18 welded together with its extension rod. , the hydraulic loading device 19 can be controlled by its own liquid crystal control panel 17 to apply a load in any range; the loading bracket 18 is provided with a loading arm 20, and the loading arm 20 is in contact with the left pipe 3 and the right pipe 21 ; The loading arm 20 can move left and right on the loading bracket 18, and the loading arm 20 and the support 11 (left support, right support) under the pipeline work together to provide different types of bending moments.

As shown in Figure 2, strain gauges 16 are evenly pasted along the outer walls of the flange, taper neck, left pipe, and right pipe, and the strain gauges 16 are evenly distributed along the circumferential direction, and the changes of the electrical signals on the strain gauges 16 are passed through the wires (rows) Line 4) is transmitted to the strain gauge 15, and the strain gauge 16 measures the stress of various parts on the flange, and displays the strain, stress and its variation with time in the strain gauge 15 and the computer 14 in real time.

The temperature sensor 12 and the pressure sensor 13 can send signals to the computer 14 for display, and can also send signals to a single-chip microcomputer for display.

Work engineering of the present utility model:

(1) Before the pipe flange stress monitoring system works under the action of external bending moment, the computer 14 is turned on for standby, the strain gauge 15 is turned on and preheated, and the switch status of the valve 2, the exhaust valve 8, and the bottom outlet valve 10 is checked;

(2) When the pipeline flange stress monitoring system works under the action of external bending moment, the pump 1 fills the cavity of the flange to be tested with the medium, and the pressure sensor 13 displays the pressure in the cavity of the flange to be tested, and adjusts the pressure to the cavity to be tested. Pressure: the temperature in the cavity to be measured of the flange is displayed by means of the temperature sensor 12. Under this working condition, the pressure is maintained for a long enough time, and the stress change on the flange is jointly monitored by the strain gauge 15 and the computer 14.

Claims (6)

1. A pipeline flange stress monitoring system under the action of an external bending moment, which includes a left pipeline, a right pipeline, and a flange connecting the left pipeline and the right pipeline, and the flange is sealed with a gasket, and the left pipeline and the right pipeline are sealed. 1. The flange forms a cavity to be tested by the flange, which is characterized in that: The left pipeline is connected to the pump through a valve, and the right pipeline is welded to a blind plate; a temperature sensor and a pressure sensor are arranged in the cavity of the flange to be measured; The system also includes an external bending moment loading mechanism and a stress testing mechanism, the external bending moment loading mechanism includes a hydraulic loading device, the hydraulic loading device applies force to the left pipe and the right pipe, and cooperates with the support, and the flange An external torque is formed on the pipeline at the joint, and the magnitude of the torque can be adjusted freely; the stress testing mechanism includes a strain gauge, and the strain gauge is connected with the strain gauge and the computer through a cable. 2. The pipeline flange stress monitoring system under the action of external bending moment as claimed in claim 1, characterized in that: the strain gauges are along the left pipeline cylindrical section, the right pipeline cylindrical section, the flange cone neck section and the flange The outer wall of the disc is evenly distributed in the circumferential direction. 3. The pipeline flange stress monitoring system under the action of external bending moment according to claim 1, characterized in that: the extension rod of the hydraulic loading device is welded together with the loading bracket, and the hydraulic loading device can provide Any size of force, the loading bracket is provided with a loading arm, and the loading arm is in contact with the left pipeline and the right pipeline. 4. The pipeline flange stress monitoring system under the action of external bending moment according to claim 1 or 3, characterized in that: the hydraulic loading device is controlled by a liquid crystal control panel. 5. The pipeline flange stress monitoring system under the action of external bending moment as claimed in claim 3, characterized in that: the loading arm can move left and right on the loading bracket, and the loading arm cooperates with the supports on the left and right pipelines , providing different types and sizes of bending moments. 6. The pipeline flange stress monitoring system under the action of external bending moment according to claim 1, characterized in that: the right pipeline is provided with an exhaust valve and a bottom outlet valve.