CN103203874B - Device and method for stripping test of electro-fusion joint - Google Patents
Device and method for stripping test of electro-fusion joint Download PDFInfo
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- CN103203874B CN103203874B CN201310125905.7A CN201310125905A CN103203874B CN 103203874 B CN103203874 B CN 103203874B CN 201310125905 A CN201310125905 A CN 201310125905A CN 103203874 B CN103203874 B CN 103203874B
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- 238000012360 testing method Methods 0.000 title claims abstract description 50
- 238000000034 method Methods 0.000 title claims abstract description 19
- 230000004927 fusion Effects 0.000 claims abstract description 15
- 238000003825 pressing Methods 0.000 claims description 34
- 238000002844 melting Methods 0.000 claims description 25
- 230000008018 melting Effects 0.000 claims description 24
- 238000003466 welding Methods 0.000 claims description 9
- 238000006073 displacement reaction Methods 0.000 claims description 4
- 238000003754 machining Methods 0.000 claims description 4
- 230000010354 integration Effects 0.000 claims description 3
- 238000012545 processing Methods 0.000 claims description 2
- 230000007613 environmental effect Effects 0.000 abstract description 2
- 230000002349 favourable effect Effects 0.000 abstract 1
- 238000009864 tensile test Methods 0.000 abstract 1
- 239000004698 Polyethylene Substances 0.000 description 11
- -1 Polyethylene Polymers 0.000 description 10
- 229920000573 polyethylene Polymers 0.000 description 10
- 238000010998 test method Methods 0.000 description 9
- 238000010586 diagram Methods 0.000 description 7
- 238000003723 Smelting Methods 0.000 description 2
- 230000001066 destructive effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 206010058031 Joint adhesion Diseases 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000007373 indentation Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 238000001304 sample melting Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229920002554 vinyl polymer Polymers 0.000 description 1
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- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention relates to a stripping test of an electro-fusion joint and aims at providing a device and method for a stripping test of an electro-fusion joint. The device comprises a carrying platform, an end plate pressure plate, a tail part pressure plate, a detachable joint and a chain, wherein the end part pressure plate, the tail part pressure plate and the carrying platform are connected through bolts and used for fixing a test sample; a carrying flat plate is further connected with the detachable joint through a bolt, and the detachable joint is linked with a lower clamp of a tensile testing machine through a pin; and one end of the chain is linked with an upper clamp of the testing machine, and the other end of the chain is connected with a towing hole formed in the test sample through the pin. According to the device provided by the invention, the effective length in the position of the combination surface of weld joints is reduced, and the strength is reduced so as to be favorable for realizing effective stripping of a high-strength joint test sample; and the difficulty in stripping a fusion area of the joint test sample is embodied, the influence of environmental factors is smaller, and the bonding strength of the joint can be objectively and quantitatively evaluated without relying on the subjective judgment of testing staff.
Description
Technical field
The present invention relates to and a kind ofly check high strength electric fusion joint adhesion strength and facilitate the disbonded test method of objective quantitative and a set of corresponding experimental rig, particularly a kind of device and method for electric fusion joint disbonded test.
Background technology
Polyethylene pipe good toughness, shock resistance, corrosion-resistant, and long service life, operation energy consumption and maintenance cost are low, obtain increasing application in fields such as oil, chemical industry, municipal administrations.Electric fusion joint is one of the most widely used connected mode of polyethylene pipe, is also the weak link of pipe-line system safety.Research shows that the dominant failure reason of electric fusion joint is that between tubing and sleeve, the adhesive property of weld interface does not reach requirement.
Disbonded test can the effective process that is stripped of analog electrical welded joint, can reflect joint peeling resistance, be considered to one of effective means evaluating polyvinyl piping materials/electric smelting bellmouth welding quality.ISO13954-1997 Peel decohesion test for PE electrofusion assemblies of nominal outside diameter greater than or equal to 90mm and domestic equivalent with it GB/T 19808-2005 " plastic pipe and pipe fitting, nominal outside diameter is more than or equal to the stretch release test of the polyethylene electric-melting assembly of 90mm ", be the Primary Reference standard of carrying out stretch release test at present.Standard describes stretch release test method in detail: the test bars cut down from electric fusion joint, vertically fixes, and under the effect of tensile load, sample melting face is stripped gradually.
Once effectively peel off require sample along or lost efficacy near melting zone plane.But research shows, the power that the power that solder bond face can bear can bear higher than sleeve and tubing itself.Therefore when the stretch release test method specified according to existing standard is to detect high-strength joint welding quality, tubing can rupture before melting face is stripped, and is difficult to realize effectively peeling off.Concrete reason is: in stripping process, and sample bears tensile load; When tensile force is less, because high-strength joint makes melting zone have very high bulk strength, weld interface can not destroy; Meanwhile, the tubing generation severe bends distortion that intensity is relatively little and stretcher strain; Tensile load continues to increase, and the polyethylene preferential yield of welding region compared by tubing place polyethylene, and before melting plane is stripped, ductile failure occurs.Therefore conventional peel test method cannot detect the melting zone quality of high-strength joint.
In addition, existing standard peels off by the destructive characteristics after tube wall, pipe wall or the stripping of fusion face and fragility the peel strength that percentage characterizes assembly.On the one hand, specimen surface destructive characteristics is subject to experimental enviroment and test operation impact, is unfavorable for the degree of accuracy ensureing testing result; On the other hand, fragility is peeled off percentage and is depended on the subjective judgement of human eye to failure mode, is unfavorable for the precision ensureing testing result.Therefore, the disbonded test method specified according to existing standard, is difficult to develop an objective quantitative index to characterize the peel strength of electric smelting assembly, constrains the further genralrlization of standard.
Along with the development of electric fusion joint technology, detected strength of joint improves constantly, and it is a kind of effective and facilitate the disbonded test method of its adhesion strength of objective quantitative for high-strength joint to need.But, there is no the disbonded test method meeting above-mentioned requirements both at home and abroad.
Summary of the invention
The technical problem to be solved in the present invention is, overcomes deficiency of the prior art, provides a kind of can being used for check high-strength joint welding quality and facilitate peel test device and the method for objective quantitative.
For technical solution problem, solution of the present invention is:
A kind of device for electric fusion joint disbonded test is provided, comprises mechanical stretch testing machine, also comprise carrying platform, end pressing plate, afterbody pressing plate, detachable connector and chain; The zone line of carrying platform upper surface, end pressing plate lower surface and afterbody pressing plate lower surface all have staggered lines in length and breadth; End pressing plate, to be bolted between afterbody pressing plate and carrying platform for fixing sample; Loading plate is also connected with detachable connector by bolt, and detachable connector and cupping machine lower clamp are connected by pin; On one end of chain and testing machine, fixture is connected, and the other end is connected with the towing pad be located on sample by pin.
Improve as one, described carrying platform has 8 tapped through holes run through, its lower surface has 4 tapped blind holes around Platform center; End pressing plate has two unthreaded holes run through, and afterbody presses off four unthreaded holes run through; Described detachable connector comprises flange and cylindrical seat, and flange has four unthreaded holes at the relative position of four screwed holes of corresponding carrying platform lower surface, and cylindrical seat has horizontal pin-and-hole.
As further goal of the invention, for the method for electric fusion joint disbonded test in the present invention, comprise the following steps:
(1) according to the requirement processing sample of GB/T 19808-2005, the groove of resistive heater upper surface is then deep in the Surface Machining one of sample electric melting sleeve, to reduce the effective length at weld seam composition surface place; And offer towing pad at the sleeve elongation end of sample, the center line being up and down centrally located at sleeve of towing pad, and equal with the distance between first resistance wire, sleeve root;
(2) sample is placed on carrying platform central authorities, fixes sample tubing extension with afterbody pressing plate and prop up the root of sample sleeve as far as possible; According to the position of towing pad in the length of sample blank area and sample, after determining the position of end pressing plate, clamp the joint of sample;
(3) be connected by fixture on one end of chain and testing machine, the other end is connected with the towing pad of sample by pin;
(4) confirm that carrying platform is close to by fixed, the tubing of sample, and towing pad center, carrying platform center is all on the central axis of upper lower clamp;
(5) disbonded test of sample is started; In whole stripping process, external applied load, perpendicular to weld interface, is mainly carried by melting zone, and the inefficacy of high-strength joint sample is located on or near welding plane, and tubing and sleeve remain intact, for once effectively peeling off; Stop test, preserve data;
(6) obtained the stretch release energy of whole stripping process by the power-displacement integration at external load function point place, be used for characterizing joint bonding intensity.
Disbonded test method of the present invention is by a set of stripping off device, sample level is fixed, and melting face realizes effectively peeling off under vertical force, is characterized the adhesion strength of joint by mechanical stretch testing machine record related data.
Sample of the present invention is processed according to the requirement of GB/T 19808-2005, then at Surface Machining groove of sample sleeve part, is deep to resistive heater upper surface, thus reduces the effective length at weld seam composition surface place.
In peel test device of the present invention, end pressing plate can adjust according to different joint samples with the relative position that afterbody pressing plate is connected from carrying platform.
Disbonded test side of the present invention ratio juris is, the tensile load that mechanical stretch testing machine is applied by chain vertically acts on joint melting face, and because batten is fixed by level firmly, external applied load is born primarily of weld interface.Along with the continuous increase of external applied load, weld seam indentation, there is opened gradually, until weld seam composition surface place tears.In whole stripping process, power and the displacement at external load function point place are recorded.
Now for prior art, beneficial effect of the present invention is:
Utilize the present invention the inefficacy of high-strength joint sample can be guided to or close welding plane, thus realize the effective stripping to high-strength joint.Be embodied in:
(1) specimen surface open channels, is divided into two parts by whole melting zone.The effective length at weld interface place reduces, and intensity reduces, and contributes to the effective stripping realizing high-strength joint sample.The polyethylene of whole melting zone is uniformly distributed, and axial mechanical property is consistent, and the adhesion strength of Gu Bufenrongrongqu can represent the adhesion strength level of the front whole melting zone of fluting;
(2) increase the roughness on apparatus parts surface, can prevent sample from skidding under the effect of external applied load or being hauled out, strengthen the fixing of sample;
(3) link position of pressing plate and carrying platform can adjust, and assurance device is to the applicability of different size high-strength joint sample;
(4) main part of device and cupping machine lower clamp are connected by detachable connector, and the tensile load by mechanics machine peels off joint samples, greatly facilitate the use of disbonded test method of the present invention;
(5) sample horizontal positioned, two ends by firm grip between carrying platform and pressing plate, bending, the stretcher strain of sample in stripping process can be prevented, thus avoid the tube portions of sample, because of large deformation, ductile failure occurs, contribute to the effective stripping realizing high-strength joint sample;
(6) whole disbonded test process, external applied load is vertical all the time with joint release surface, can prevent sample from being hauled out by level on the one hand, be conducive to the fixing of sample, external applied load carries primarily of melting zone on the other hand, not only contribute to the effective stripping realizing high-strength joint sample, also can get rid of the impact of tubing carrying on testing result;
(7) the relevant Mechanical Data of testing machine system log (SYSLOG), embodies the complexity peeling off joint samples melting zone, less by such environmental effects, and does not rely on the subjective judgement of testing crew, can be used for objective quantitative joint bonding intensity.
Accompanying drawing explanation
Fig. 1 electric fusion joint sample structure schematic diagram;
The carrying platform schematic diagram of Fig. 2 specific embodiment of the invention;
The end pressing plate schematic diagram of Fig. 3 specific embodiment of the invention;
The afterbody pressing plate schematic diagram of Fig. 4 specific embodiment of the invention;
The detachable connector schematic diagram of Fig. 5 specific embodiment of the invention;
The apparatus main body schematic diagram of Fig. 6 specific embodiment of the invention;
The test assembling schematic diagram of Fig. 7 specific embodiment of the invention.
Reference numeral in Fig. 1: electric melting sleeve 1, resistive heater 2, groove 3, towing pad 4, polyethylene pipe 5, actual stripping area 6;
Reference numeral in Fig. 6: carrying platform 7, end pressing plate 8, packing ring 9, afterbody pressing plate 10, hexagon socket head cap screw 11, detachable connector 12.
Detailed description of the invention
Sample to be detected: require the sample to be detected made according to GB/T 19808-2005, be deep to the narrow groove 3 of resistive heater 2 upper surface in the Surface Machining one of sample electric melting sleeve 1, groove 3 is between the 6th and the 7th resistance wire.Towing pad is offered, the center line being up and down centrally located at sleeve of towing pad at the sleeve elongation end of sample, and equal with the distance between first resistance wire, sleeve root.As Fig. 1.
As shown in Figure 2, carrying platform 7 has 8 tapped through holes to the carrying platform 7 of peel test device, and lower surface has 4 tapped blind holes around Platform center, and upper surface central area is processed with staggered lines in length and breadth.As shown in Figure 3, end pressing plate 8 has two unthreaded holes to end pressing plate 8, and its lower surface is processed with lines.As shown in Figure 4, afterbody pressing plate 10 has four unthreaded holes to afterbody pressing plate 10, and its lower surface is processed with lines.Detachable connector 12 comprises flange and cylindrical seat as Fig. 5, and flange, at the relative position of four screwed holes of corresponding carrying platform 7 lower surface, has four unthreaded holes, cylindrical seat has pin-and-hole.
End pressing plate 8, afterbody pressing plate 10 are connected with carrying platform 7 by hex bolts with detachable connector 12, the assembling of finishing device main body, as shown in Figure 6.Utilize pin to be connected with mechanical stretch testing machine by detachable connector, device installs.
In the present embodiment, the disbonded test of electric fusion joint is implemented according to following steps:
(1) sample is placed on the rough region of carrying platform 7 central authorities, polyethylene pipe 5 extension of sample is fixed with afterbody pressing plate 10, the root of electric melting sleeve 1 will be propped up as far as possible, according to the length of blank area and the position of towing pad 4, determine the joint of the position clamping sample of end pressing plate 8, as shown in Figure 7;
(2) one end of chain is connected with sample by pin, the upper fixture of the other end direct joint test machine;
(3) confirm that device is installed correct, sample is fixed, and input test parameters, starts disbonded test;
(4) for the sample of Fig. 1 form, sample welding plane is finally as follows by the basic process of complete strip off: along with the increase of additional tensile load, and sample batten, at towing pad 4 place, slight flexural deformation occurs.Then in towing pad side, efficient melting district, the gap between electric melting sleeve 1 and polyethylene pipe 5 is opened, and melting zone starts to be torn.Along with the continuation of external applied load increases, weld seam breach opens gradually, and electric fuse comes off gradually, until whole weld seam composition surface place tears.In whole stripping process, external applied load, perpendicular to weld interface, is mainly carried by melting zone, and the inefficacy of high-strength joint sample is located on or near welding plane, and polyethylene pipe 5 and electric melting sleeve 1 remain intact, for once effectively peeling off.Stop test, preserve data;
(5) obtained the stretch release energy of whole stripping process by the power-displacement integration at external load function point place, be used for characterizing joint bonding intensity.
What enumerate it is also to be noted that above is only specific embodiments of the invention.Obviously, the present invention does not limit above embodiment, can also have many distortion.Those of ordinary skill in the art can directly derive from content disclosed by the invention or contact all distortion expected, all should think protection scope of the present invention.
Claims (3)
1. for electric fusion joint peel test device, comprise mechanical stretch testing machine, it is characterized in that, also comprise carrying platform, end pressing plate, afterbody pressing plate, detachable connector and chain; The zone line of carrying platform upper surface, end pressing plate lower surface and afterbody pressing plate lower surface all have staggered lines in length and breadth; End pressing plate, to be bolted between afterbody pressing plate and carrying platform for fixing sample; Carrying platform is also connected with detachable connector by bolt, and detachable connector and cupping machine lower clamp are connected by pin; On one end of chain and testing machine, fixture is connected, and the other end is connected with the towing pad be located on sample by pin.
2. device according to claim 1, is characterized in that, described carrying platform has 8 tapped through holes run through, and its lower surface has 4 tapped blind holes around Platform center; End pressing plate has two unthreaded holes run through, and afterbody presses off four unthreaded holes run through; Described detachable connector comprises flange and cylindrical seat, and flange has four unthreaded holes at the relative position of four screwed holes of corresponding carrying platform lower surface, and cylindrical seat has horizontal pin-and-hole.
3. for the method for electric fusion joint disbonded test, it is characterized in that, comprise the following steps:
(1) according to the requirement processing sample of GB/T 19808-2005, the groove of resistive heater upper surface is then deep in the Surface Machining one of sample electric melting sleeve, to reduce the effective length at weld seam composition surface place; And offer towing pad at the sleeve elongation end of sample, the center line being up and down centrally located at sleeve of towing pad, and equal with the distance between first resistance wire, sleeve root;
(2) sample is placed on carrying platform central authorities, fixes sample tubing extension with afterbody pressing plate and prop up the root of sample sleeve as far as possible; According to the position of towing pad in the length of sample blank area and sample, after determining the position of end pressing plate, clamp the joint of sample;
(3) be connected by fixture on one end of chain and testing machine, the other end is connected with the towing pad of sample by pin;
(4) confirm that carrying platform is close to by fixed, the tubing of sample, and towing pad center, carrying platform center is all on the central axis of upper lower clamp;
(5) disbonded test of sample is started; In whole stripping process, external applied load, perpendicular to weld interface, is mainly carried by melting zone, and the inefficacy of joint samples is located on or near welding plane, and tubing and sleeve remain intact, for once effectively peeling off; Stop test, preserve data;
(6) obtained the stretch release energy of whole stripping process by the power-displacement integration at external load function point place, be used for characterizing joint bonding intensity.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310125905.7A CN103203874B (en) | 2013-04-11 | 2013-04-11 | Device and method for stripping test of electro-fusion joint |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201310125905.7A CN103203874B (en) | 2013-04-11 | 2013-04-11 | Device and method for stripping test of electro-fusion joint |
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| CN103203874A CN103203874A (en) | 2013-07-17 |
| CN103203874B true CN103203874B (en) | 2015-05-20 |
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| CN105277794B (en) * | 2015-11-19 | 2018-06-08 | 广州供电局有限公司 | Cable connector crimps the measuring method and system of resistance |
| CN116967583A (en) * | 2023-09-22 | 2023-10-31 | 中汽研（天津）汽车工程研究院有限公司 | Spot welding sample preparation test system and clamping device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101594963A (en) * | 2006-09-16 | 2009-12-02 | 申克索诺系统有限责任公司 | Be used for when ultrasonic bonding, carrying out the method for quality-monitoring |
| CN102009474A (en) * | 2010-08-31 | 2011-04-13 | 浙江大学 | Method for testing welding quality of electro-fusion joint and realizing automatic evaluation |
| CN102285120A (en) * | 2011-07-27 | 2011-12-21 | 浙江大学 | Method for determining electro-fusion joint cold-welding defects |
| CN203259456U (en) * | 2013-04-11 | 2013-10-30 | 浙江大学 | Device for electric fusion joint peeling test |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4603680B2 (en) * | 2000-12-22 | 2010-12-22 | 大日本プラスチックス株式会社 | Welding confirmation method for thermoplastic resin pipe joints |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101594963A (en) * | 2006-09-16 | 2009-12-02 | 申克索诺系统有限责任公司 | Be used for when ultrasonic bonding, carrying out the method for quality-monitoring |
| CN102009474A (en) * | 2010-08-31 | 2011-04-13 | 浙江大学 | Method for testing welding quality of electro-fusion joint and realizing automatic evaluation |
| CN102285120A (en) * | 2011-07-27 | 2011-12-21 | 浙江大学 | Method for determining electro-fusion joint cold-welding defects |
| CN203259456U (en) * | 2013-04-11 | 2013-10-30 | 浙江大学 | Device for electric fusion joint peeling test |
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Application publication date: 20130717 Assignee: NINGBO AOPU PIPE TECHNOLOGY CO., LTD. Assignor: Zhejiang University Contract record no.: 2013330000400 Denomination of invention: Device and method for stripping test of electro-fusion joint License type: Exclusive License Record date: 20131220 |
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