CN104122042A - Pressure resistance testing method of large-diameter welding structure metal pipeline - Google Patents
Pressure resistance testing method of large-diameter welding structure metal pipeline Download PDFInfo
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- CN104122042A CN104122042A CN201410342202.4A CN201410342202A CN104122042A CN 104122042 A CN104122042 A CN 104122042A CN 201410342202 A CN201410342202 A CN 201410342202A CN 104122042 A CN104122042 A CN 104122042A
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- welded structure
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Abstract
The invention provides a pressure resistance testing method which can be used for a high-pressure operation welding structure metal pipeline. The pressure resistance testing method comprises the steps of performing water filling and pressurization on a small-size annular sealing cavity between the welding structure metal pipeline to be tested and a built-in concentric metal tubular part, and evaluating the pressure resistance capacity of the high-pressure operation welding structure metal pipeline. By adoption of the pressure resistance testing method and decrease of pressure-bearing areas of sealing plates at two ends of the pipeline, the axial stress degree of the sealing plates at two ends is reduced, and further the safety of connecting portions of the sealing plates and the welding structure metal pipeline to be tested is ensured. When the connecting portions of the sealing plates and the welding structure metal pipeline to be tested are identical in connecting strength and compared with a traditional pipeline pressure-bearing testing method, a device adopted by the method can achieve pressure-bearing testing of high pressure in the welding structure metal pipeline and meanwhile can save more energy and more environment-friendly.
Description
Technical field
The present invention relates to major diameter welded structure metallic conduit 1 to carry out resistance test technical field, is a kind of structure withstand voltage test method of welded structure metallic conduit 1.
Background technology
Welded structure metallic conduit is a kind of conventional transmission system member, can be used for the every field such as oil transportation, water delivery, gas transmission.The voltage endurance capability of welded structure metallic conduit and sealing are to weigh the major criterion of its quality of production.In order to guarantee the security in welded structure metallic conduit military service process, according to relevant criterion, conventionally before formal use, it is carried out to voltage-withstand test.Traditional pipeline withstand voltage test method is: 1), pipe ends is adopted to seal pad sealing, sealing means can adopt welding, and the mode that also can adopt flange to coordinate with O-ring seal realizes; 2), by water filling or gas injection in provided pipe road direction annular seal space, suppress external tensimeter monitoring pressure in real time value; 3), under the testing pressure of setting standing certain hour, whether have the situation of leaking or ftractureing, obtain its voltage endurance capability if observing pipe under test outer wall.
When pipe diameter is larger, for example, when pipe diameter is greater than 500mm, concrete voltage-withstand test mode as shown in Figure 1, by welded structure metallic conduit to be measured (1) and convex seal pad (2) sealing, on seal pad (2) top, reserved exhausr port (3) and water inlet (4), be sidelong and put tensimeter (5) at water inlet (4).Suppose that pipe diameter is D, test pressure is P, while adopting this kind of conventional pipelines withstand voltage test method, pipeline and seal pad connecting portion axially loaded F can be expressed as:
F＝πPD
2/4
By above-mentioned formula, can be found out, while adopting the voltage endurance capability of classic method testing conduit, pipeline and seal pad square being directly proportional of connecting portion axially loaded and pipe under test diameter.Therefore,, when pipe diameter becomes large, pipeline is often stressed larger than tube wall to be measured with the connecting portion of seal, carry out in this case voltage-withstand test, conventionally the risk that exists pipeline and seal connecting portion to lose efficacy in advance, and then cause the voltage endurance capability test crash to tube wall, even cause security incident.
Summary of the invention
The invention provides a kind of security performance high, water consumption is few, and can be used for the withstand voltage test method of the welded structure metallic conduit of high hydraulic pressure test.Technical scheme of the present invention is:
1) in voltage-withstand test welded structure metallic conduit (1) inner concentric position, insert an assistant metal tube-like piece (6) that length is smaller;
2) adopt circular weld (10) assistant metal tube-like piece (6) one end external diameter of welding to be greater than to external diameter, the internal diameter metallic ring-plate (7) identical with assistant metal tube-like piece (6) internal diameter of voltage-withstand test welded structure metallic conduit (1), and metallic ring-plate (7) and voltage-withstand test welded structure metallic conduit (1) are tightly connected;
3) assistant metal tube-like piece (6) is welded to the internal diameter that an external diameter is less than voltage-withstand test welded structure metallic conduit (1) in one end in addition, internal diameter is less than the metallic ring-plate (9) of assistant metal tube-like piece (6) internal diameter;
4) in assistant metal tube-like piece (6) inside, install support reinforcing ring flat-plate (14) additional;
5) adopt middle cushion rubber (12) sealing annular metal sheet (8) and metallic ring-plate (9), adopt afterwards double-screw bolt (11) fastening, the reserved vent port (13) in annular metal sheet (8) surface and inlet opening;
6) seal welding annular metal sheet (8) and voltage-withstand test welded structure metallic conduit (1) have formed the annular seal space of reserved inlet opening and vent port (13) between voltage-withstand test welded structure metallic conduit (1) and assistant metal tube-like piece (6);
7) by inlet opening to water filling in annular seal space, air in vent port (13) discharge side, air drains rear employing welded seal or rubber sealing mode is carried out shutoff to vent port (13);
8) continue, to water filling pressurization in inlet opening, to adopt tensimeter Real-Time Monitoring, reach standing a period of time after test pressure, observe sealing and the withstand voltage properties of welded structure metallic conduit (1).
Technique effect:
The invention provides a kind of withstand voltage test method of welded structure metallic conduit, and device corresponding to the method and assembling mode are provided, there is following technological merit: the pressure of 1, supposing voltage-withstand test is P, the welded structure metallic conduit internal diameter of voltage-withstand test is D, the external diameter of assistant welding structure metallic conduit is d,, in voltage-withstand test process, pipeline end face connecting portion axially loaded F can be expressed as: F=π P (D
2-d
2)/4, with conventional test methodologies ratio, the present invention, by built-in assistant metal pipe, has reduced the axially loaded degree of pipeline end face connecting portion.And, adopt method provided by the invention, any inside diameter D for different voltage-withstand test metal tubes, and test pressure P arbitrarily, by adjusting the outside diameter d of built-in metal pipe, all the axially loaded F of welcome adjustment connecting portion, makes it in tolerance zone, so the present invention can be used for the elevated pressures voltage-withstand test of major diameter welded structure metallic conduit; 2, according to method provided by the invention, when voltage-withstand test welded structure metallic conduit wall thickness is greater than assistant metal tube-like piece wall thickness, or voltage-withstand test metal tube test pressure requires higher than 10MPa, or voltage-withstand test metal tube length-diameter ratio is greater than at 3 o'clock, in assistant metal tube-like piece inside, install one or more support reinforcing ring flat-plates additional, support reinforcing ring flat-plate can promote the bearing capacity of built-in assistant metal tube-like piece greatly, has guaranteed that it can not be out of shape or lose efficacy under test pressure.
Accompanying drawing explanation
Fig. 1 is traditional welding structural metal pipeline voltage-withstand test schematic diagram.
Fig. 2 is that two ends are without the welded structure metal circular tube pressure resistant testing device wiring layout of flange-interface.
Fig. 3 is the welded structure metal circular tube pressure resistant testing device wiring layout of the flanged interface in one end.
In accompanying drawing
1 welded structure metal tube; 2 convex seal pads;
3 exhausr ports; 4 water inlets;
5 tensimeters; 6 assistant metal tube-like pieces;
7 annular metal sheets; 8 annular metal sheets;
9 open the metallic ring-plate of threaded hole; 10 weld seams;
11 double-screw bolts; 12 cushion rubbers;
13 vent ports; 14 support reinforcing ring flat-plates;
The 15 flanged (FLGD) welded structure metal circular tubes in end; 16 bolts;
17 cushion rubbers.
Embodiment:
The present invention is that a kind of security performance is high, and water consumption is few, and can be used for the withstand voltage test method of the welded structure metallic conduit of high hydraulic pressure test, its for welded structure metallic conduit diameter be more than or equal to 500mm, the specific embodiment of the present invention is:
Embodiment mono-: as shown in Figure 2, the voltage-withstand test welded structure metallic conduit 1 that there is no flange for two ends, its pressure resistant testing device and concrete implementation step are as follows: 1), in voltage-withstand test welded structure metallic conduit 1 inner concentric position, insert an assistant metal tube-like piece 6 that length is smaller; 2), assistant metal tube-like piece 6 one end external diameters of welding are greater than to external diameter, the internal diameter metallic ring-plate 7 identical with assistant metal tube-like piece 6 internal diameters of voltage-withstand test welded structure metallic conduit 1, its weld seam is 10, and by metallic ring-plate 7 and voltage-withstand test welded structure metallic conduit 1 seal welding; 3), the other one end of assistant metal tube-like piece 6 external diameter of welding is less than to the internal diameter of voltage-withstand test welded structure metallic conduit 1, internal diameter is less than the metallic ring-plate 9 of assistant metal tube-like piece 6 internal diameters; 4), when voltage-withstand test welded structure metallic conduit 1 wall thickness is greater than assistant metal tube-like piece 6 wall thickness, or voltage-withstand test welded structure metallic conduit 1 test pressure requires higher than 5MPa, or the length-diameter ratio of voltage-withstand test metal tube 1 is greater than at 3 o'clock, in assistant metal tube-like piece 6 inside, install one or more support reinforcing ring flat-plates 14 additional; 5), to adopt annular metal sheet 8 sealing metal ring flat-plates 9, sealing means be that double-screw bolt 11 is fastening after middle cushion rubber 12 sealings, the annular metal sheet 8 reserved vent port 13 in surface and inlet openings; 6), adopt annular metal sheet 8 sealing voltage-withstand test welded structure metallic conduits 1, sealing means is welded seal.So far, between voltage-withstand test welded structure metallic conduit 1 and assistant metal tube-like piece 6, formed the annular seal space of reserved inlet opening and vent port 13; 7), by inlet opening to water filling in annular seal space, air in vent port 13 discharge sides, air drains rear employing welded seal or rubber sealing mode is carried out shutoff to vent port 13; 8), continue, to water filling pressurization in inlet opening, to adopt tensimeter Real-Time Monitoring, reach shutoff water inlet after test pressure; 9), under test pressure standing a period of time, according to relevant criterion, observe sealing and the withstand voltage properties of pipeline.
Embodiment bis-: as shown in Figure 3, for one end flanged (FLGD) voltage-withstand test welded structure metallic conduit 15, its pressure resistant testing device and concrete implementation step are as follows: 1), in voltage-withstand test welded structure metallic conduit 1 inner concentric position, insert an assistant metal tube-like piece 6 that length is smaller; 2), assistant metal tube-like piece 6 one end external diameters of welding are greater than to external diameter, the internal diameter metallic ring-plate 7 identical with assistant metal tube-like piece 6 internal diameters of voltage-withstand test welded structure metallic conduit 1, its weld seam is 10, and metallic ring-plate 7 and voltage-withstand test welded structure metallic conduit 15 flanged plates are adopted to cushion rubber 17 sealings, bolt 16 is fastening; 3), the other one end of assistant metal tube-like piece 6 external diameter of welding is less than to the internal diameter of voltage-withstand test welded structure metallic conduit 1, internal diameter is less than the metallic ring-plate 9 of assistant metal tube-like piece 6 internal diameters; 4), when voltage-withstand test welded structure metallic conduit 1 wall thickness is greater than assistant metal tube-like piece 6 wall thickness, or voltage-withstand test welded structure metallic conduit 1 test pressure requires higher than 5MPa, or the length-diameter ratio of voltage-withstand test metal tube 1 is greater than at 3 o'clock, in assistant metal tube-like piece 6 inside, install one or more support reinforcing ring flat-plates 14 additional; 5), to adopt annular metal sheet 8 sealing metal ring flat-plates 9, sealing means be that double-screw bolt 11 is fastening after middle cushion rubber 12 sealings, the annular metal sheet 8 reserved vent port 13 in surface and inlet openings; 6), adopt annular metal sheet 8 sealing voltage-withstand test welded structure metallic conduits 1, sealing means is welded seal.So far, between voltage-withstand test welded structure metallic conduit 1 and assistant metal tube-like piece 6, formed the annular seal space of reserved inlet opening and vent port 13; 7), by inlet opening to water filling in annular seal space, air in vent port 13 discharge sides, air drains rear employing welded seal or rubber sealing mode is carried out shutoff to vent port 13; 8), continue, to water filling pressurization in inlet opening, to adopt tensimeter Real-Time Monitoring, reach shutoff water inlet after test pressure; 9), under test pressure standing a period of time, according to relevant criterion, observe sealing and the withstand voltage properties of pipeline.
For the equal flanged (FLGD) voltage-withstand test welded structure metallic conduit in both sides, its pressure resistant testing device and embodiment reference implementation scheme two are carried out, unique different be that its two end flanges side all adopts rubber sealing, bolted.
The welded structure metallic conduit withstand voltage test method that the present invention proposes, security increases substantially, more energy-conservation, more environmental protection; In addition, for large diameter welded structure metallic conduit, or the larger welded structure metallic conduit of length, the device water consumption that the inventive method relates to is little, and testable pressure is higher.
Finally, protection scope of the present invention is not limited to the above embodiments.Obviously, those skilled in the art can carry out various changes and distortion and not depart from the scope of the present invention and spirit the present invention.If these changes and distortion belong in the scope of the claims in the present invention and equivalent technologies thereof, the present invention is also intended to comprise these changes and is out of shape interior.
Claims (8)
1. a withstand voltage test method for major diameter welded structure metallic conduit, is characterized in that:
This technique comprises the steps:
1) in voltage-withstand test welded structure metallic conduit (1) inner concentric position, insert an assistant metal tube-like piece (6) that length is smaller;
2) adopt circular weld (10) assistant metal tube-like piece (6) one end external diameter of welding to be greater than to external diameter, the internal diameter metallic ring-plate (7) identical with assistant metal tube-like piece (6) internal diameter of voltage-withstand test welded structure metallic conduit (1), and metallic ring-plate (7) and voltage-withstand test welded structure metallic conduit (1) are tightly connected;
3) assistant metal tube-like piece (6) is welded to the internal diameter that an external diameter is less than voltage-withstand test welded structure metallic conduit (1) in one end in addition, internal diameter is less than the metallic ring-plate (9) of assistant metal tube-like piece (6) internal diameter;
4) in assistant metal tube-like piece (6) inside, install support reinforcing ring flat-plate (14) additional;
5) adopt middle cushion rubber (12) sealing annular metal sheet (8) and metallic ring-plate (9), adopt afterwards double-screw bolt (11) fastening, the reserved vent port (13) in annular metal sheet (8) surface and inlet opening;
6) seal welding annular metal sheet (8) and voltage-withstand test welded structure metallic conduit (1) have formed the annular seal space of reserved inlet opening and vent port (13) between voltage-withstand test welded structure metallic conduit (1) and assistant metal tube-like piece (6);
7) by inlet opening to water filling in annular seal space, air in vent port (13) discharge side, air drains rear employing welded seal or rubber sealing mode is carried out shutoff to vent port (13);
8) continue, to water filling pressurization in inlet opening, to adopt tensimeter Real-Time Monitoring, reach standing a period of time after test pressure, observe sealing and the withstand voltage properties of welded structure metallic conduit (1).
2. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, is characterized in that: welded structure metallic conduit (1) internal diameter that adopts the method to carry out voltage-withstand test is more than or equal to 500mm.
3. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, is characterized in that: the internal diameter of accepting the welded structure metallic conduit (1) of voltage-withstand test is greater than the external diameter of assistant metal tube-like piece (6).
4. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, it is characterized in that: when accepting voltage-withstand test welded structure metallic conduit (1) wall thickness and be greater than assistant metal tube-like piece (6) wall thickness, in assistant metal tube-like piece (6) inside, install support reinforcing ring flat-plate (14) additional.
5. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, it is characterized in that: when welded structure metallic conduit (1) test pressure requires higher than 10MPa, in assistant metal tube-like piece (6) inside, install support reinforcing ring flat-plate (14) additional.
6. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, it is characterized in that: when welded structure metallic conduit (1) length-diameter ratio is greater than 3, in assistant metal tube-like piece (6) inside, install support reinforcing ring flat-plate (14) additional.
7. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, is characterized in that: when voltage-withstand test metal tube (1) end cannot be blue, by its end and butt-end packing plate (7) and (8) employing welded seal.
8. the withstand voltage test method of major diameter welded structure metallic conduit according to claim 1, it is characterized in that: when there is flange voltage-withstand test metal tube (1) end, the flange that can match in the configuration of assistant metal tube-like piece (6) end, adopts bolt (16) merging with cushion rubber (17) sealing between two flanges.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410342202.4A CN104122042B (en) | 2014-07-18 | 2014-07-18 | A kind of voltage-withstand test method of major diameter welding structure metallic conduit |
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|---|---|---|---|
| CN201410342202.4A CN104122042B (en) | 2014-07-18 | 2014-07-18 | A kind of voltage-withstand test method of major diameter welding structure metallic conduit |
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| Publication Number | Publication Date |
|---|---|
| CN104122042A true CN104122042A (en) | 2014-10-29 |
| CN104122042B CN104122042B (en) | 2017-07-11 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104865127A (en) * | 2015-04-07 | 2015-08-26 | 昆明理工大学 | Testing apparatus and detection method for welding strength of plastic sewer inspection pit |
| CN106442157A (en) * | 2016-12-07 | 2017-02-22 | 贵州黎阳航空动力有限公司 | Subarea detection casing hydraulic strength testing device |
| CN107860661A (en) * | 2017-10-25 | 2018-03-30 | 李厚兵 | A kind of high pressure resistant oil-gas pipeline hydraulic pressure testing device |
| CN110398420A (en) * | 2019-08-19 | 2019-11-01 | 艾尔希庆华(西安)汽车有限公司 | A kind of quick-fried reinspection test method of gas generator liquid |
| CN112179569A (en) * | 2020-09-18 | 2021-01-05 | 中国水利水电第五工程局有限公司 | Water supply steel pipe hydrostatic test inner plugging head and plugging method thereof |
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| CN103558090A (en) * | 2013-11-18 | 2014-02-05 | 中建五局工业设备安装有限公司 | Water pressure testing device and method for single joint of major-diameter pressure-bearing pipeline |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104865127A (en) * | 2015-04-07 | 2015-08-26 | 昆明理工大学 | Testing apparatus and detection method for welding strength of plastic sewer inspection pit |
| CN106442157A (en) * | 2016-12-07 | 2017-02-22 | 贵州黎阳航空动力有限公司 | Subarea detection casing hydraulic strength testing device |
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| CN112179569A (en) * | 2020-09-18 | 2021-01-05 | 中国水利水电第五工程局有限公司 | Water supply steel pipe hydrostatic test inner plugging head and plugging method thereof |
| CN112179569B (en) * | 2020-09-18 | 2021-06-15 | 中国水利水电第五工程局有限公司 | Water supply steel pipe hydrostatic test inner plugging head and plugging method thereof |
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