CN109406325B - Method for testing wear resistance of electric detonator leg wire - Google Patents
Method for testing wear resistance of electric detonator leg wire Download PDFInfo
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- CN109406325B CN109406325B CN201811558848.0A CN201811558848A CN109406325B CN 109406325 B CN109406325 B CN 109406325B CN 201811558848 A CN201811558848 A CN 201811558848A CN 109406325 B CN109406325 B CN 109406325B
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- wire
- leg wire
- detonator
- detonator leg
- pivot rod
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/56—Investigating resistance to wear or abrasion
Abstract
The invention discloses a method for testing the wear resistance of a detonator leg wire, which is characterized in that a certain action load is applied to the tested detonator leg wire on a detonator leg wire wear resistance testing device, the tested detonator leg wire is enabled to move on a wear surface at a certain speed, the wear action force applied to the tested detonator leg wire is simulated, the time for an insulating layer to be worn is measured, and the wear resistance of the leg wire is evaluated through the worn time. And discloses the structure of the electric detonator leg wire wear resistance testing device. The method is simple and easy to implement, the testing device is compact in structural design and small in occupied area, the electric detonator leg wire is matched with the tension measuring mechanism, the wire pressing mechanism, the wire guiding mechanism, the tension adjusting mechanism, the rotating mechanism and the like which are sequentially arranged on the frame, the failure rate is low, the reliability is high, and meanwhile, the efficiency of testing the abrasion resistance of the detonator leg wire is improved.
Description
Technical Field
The invention relates to a method and a device for testing the wear resistance of a leg wire of an electric detonator, which are mainly used for simulating the phenomenon that the leg wire of the electric detonator is likely to be worn out and accidently fails in the production, transportation and use processes, and belong to the technical field of explosive detection equipment.
Background
With the rapid development of mining industry and blasting engineering, the demand for detonators is increasing. The detonators are classified into non-electric detonators and electric detonators, wherein the electric detonators comprise industrial electric detonators, electronic detonators and magnetoelectric detonators, and the quantity of the electric detonators is hundreds of millions each year in China. The electric detonator is often out of function due to the damage of the leg wire. The foot wire is worn to cause the short circuit of the two foot wires, the detonator can not be detonated, and the explosive can not be detonated. This will have a significant impact on the engineering blasting and may cause a significant safety accident.
The electric detonator leg wire wear-resisting property testing device is used for simulating the phenomenon that the leg wire is likely to be worn through and accidentally fails in the production, transportation and use processes of the electric detonator. At present, no experimental method for testing the wear resistance of the electric detonator leg wire is established in China, and no equipment of the type is available. If the abrasion resistance of the electric detonator leg wire cannot be reasonably tested, the intrinsic safety level of the detonator is seriously influenced. The existing detonator leg wire wear resistance test mainly adopts manual operation, and only one leg wire can be tested at a time.
In actual production, a detonator leg wire wear-resisting property testing device which is compact in structure, high in efficiency, safe and reliable is needed so as to meet the requirements of actual production.
Disclosure of Invention
The invention aims to provide a method and a device for testing the wear resistance of the electric detonator leg wire, aiming at the defect of the capability of testing the wear resistance of the electric detonator leg wire in the prior art.
In order to achieve the purpose, the invention adopts the following solution: a method for testing the wear-resisting performance of the foot wire of detonator includes such steps as applying a certain action load to the foot wire of electric detonator to be tested, moving it at a certain speed on the wearing surface, simulating the action of the foot wire of electric detonator to be worn, measuring the time for wearing the insulating layer, and evaluating the wear-resisting performance of the foot wire.
Furthermore, the detonator leg wire wear resistance testing device comprises a rack, a tension measuring mechanism, a wire pressing mechanism, a rotating mechanism, a wire guiding mechanism and a tension adjusting mechanism, wherein the tension measuring mechanism, the wire pressing mechanism, the rotating mechanism, the wire guiding mechanism and the tension adjusting mechanism are arranged on the rack; one end of the detonator leg wire is fixed on the tension measuring mechanism, the other end of the detonator leg wire penetrates through the wire guide mechanism and is fixed by the tension adjusting mechanism, and the part to be tested of the detonator leg wire is horizontally placed at the test starting position between the wire pressing mechanism and the rotating mechanism.
Furthermore, the detonator leg wire wear-resisting property testing device also comprises a PLC control system, and the PLC control system controls the components to start and stop according to a logic sequence.
Furthermore, the tension measuring mechanism comprises a gravity sensor and a leg wire fixing nut, the gravity sensor is installed on the rack, and the leg wire fixing nut is installed on the gravity sensor and used for connecting one end of the leg wire of the tested electric detonator.
Furthermore, the wire pressing mechanism comprises a pivot rod seat, a pivot rod, a counterweight rod and a counterweight; the pivot rod seat is arranged on the rack, one end of the pivot rod is connected with the pivot rod seat, the other end of the pivot rod is connected with the counterweight rod, and the counterweight is arranged on the counterweight rod; the lower part of the connecting side of the pivot rod and the counterweight rod is provided with an arc grinding head, and load is applied to the tested leg wire through the rod and the weight.
Furthermore, the rotating mechanism comprises a main shaft, a rotor, a sleeve and a motor; the motor is connected with the main shaft, the sleeve is arranged on the main shaft, and the rotor is arranged on the sleeve.
Furthermore, the rotor is shaped like an equilateral triangle, and the outer surface of each side is pasted with an abrasive belt made of wear-resistant steel, so that good contact between the abrasive belt and the rotor is ensured.
Furthermore, the wire guide mechanism comprises a bearing fixing plate, a wire inlet guide plate and a wire outlet guide plate; the wire inlet guide plate and the wire outlet guide plate are arranged on the rack, and the bearing fixing plate is arranged on the wire inlet guide plate and the wire outlet guide plate and is positioned between the wire inlet guide plate and the wire outlet guide plate.
Furthermore, the tension adjusting mechanism comprises a pulley seat, two pulleys, a pulley shaft and an adjusting nut, wherein the pulley shaft is arranged on the pulley seat, the two pulleys are respectively arranged on two sides of the pulley shaft, the adjusting nut is arranged on the pulley, and the adjusting nut fixes the leg wire at different positions of the pulley according to the size of the required tensile load.
The invention has the beneficial effects that: the method is simple and easy to implement, the testing device is compact in structural design and small in occupied area, the electric detonator leg wire is matched with the tension measuring mechanism, the wire pressing mechanism, the wire guiding mechanism, the tension adjusting mechanism, the rotating mechanism and the like which are sequentially arranged on the rack, the fault rate is low, the reliability is high, and meanwhile, the efficiency of testing the abrasion resistance of the detonator leg wire is improved.
Drawings
The present invention will be described in detail with reference to examples.
FIG. 1: is a structural schematic diagram of the invention;
FIG. 2: is a structural schematic diagram of the rotating mechanism of the invention;
FIG. 3: is a schematic structural diagram of the tension adjusting mechanism.
In the figure: 1. the device comprises a rack, 2, a tension measuring mechanism, 21, a gravity sensor, 22, a leg wire fixing nut, 3, a wire pressing mechanism, 31, a pivot rod seat, 32, a pivot rod, 33, a balance weight, 34, a balance weight, 4, a rotating mechanism, 41, a main shaft, 42, a rotor, 43, a sleeve, 44, a motor, 5, a wire guiding mechanism, 51, a wire inlet guide plate, 52, a bearing fixing plate, 53, a wire outlet guide plate, 6, a tension adjusting mechanism, 61, a pulley seat, 62, a pulley shaft, 63, a pulley, 64 and an adjusting nut.
Detailed Description
Example 1
A method for testing the wear-resisting performance of the foot wire of detonator includes such steps as applying a certain action load to the foot wire of electric detonator to be tested, moving it at a certain speed on the wearing surface, simulating the action of the foot wire of electric detonator to be worn, measuring the time for wearing the insulating layer, and evaluating the wear-resisting performance of the foot wire.
Example 2
As a test device of embodiment 1, as shown in fig. 1, the detonator leg wire wear resistance test device includes a frame 1, a tension measuring mechanism 2 mounted on the frame, a wire pressing mechanism 3, a rotating mechanism 4, a wire guiding mechanism 5, and a tension adjusting mechanism 6; one end of the detonator leg wire is fixed on the tension measuring mechanism 2, the other end of the detonator leg wire passes through the wire guiding mechanism 5 and is fixed by the tension adjusting mechanism 6, and the part to be tested of the detonator leg wire is horizontally placed at the testing initial position between the wire pressing mechanism 3 and the rotating mechanism 4.
The detonator leg wire wear-resisting property testing device further comprises a PLC control system, and the PLC control system controls the components to start and stop according to a logic sequence.
Example 3
As shown in fig. 1, 2 and 3, as an optimization of embodiment 2, the tension measuring mechanism 2 includes a gravity sensor 21 and a leg wire fixing nut 22, the gravity sensor 21 is mounted on the rack 1, and the leg wire fixing nut 22 is mounted on the gravity sensor 21 and is used for connecting one end of a leg wire of the tested electric detonator.
The wire pressing mechanism 3 comprises a pivot rod seat 31, a pivot rod 32, a counterweight rod 33 and a counterweight 34; the pivot rod seat 31 is arranged on the frame 1, one end of the pivot rod 32 is connected with the pivot rod seat 31, the other end is connected with the counterweight rod 33, and the counterweight weight 34 is arranged on the counterweight rod 33; the arc grinding head is arranged at the lower part of the connecting side of the pivot rod 32 and the balance weight rod 33, and the load is applied to the tested leg wire through the rod and the balance weight.
The rotating mechanism 4 comprises a main shaft 41, a rotor 42, a sleeve 43 and a motor 44; the motor 44 is connected to the main shaft 41, the sleeve 43 is mounted on the main shaft 41, and the rotor 42 is mounted on the sleeve 43.
The rotor 42 is shaped like an equilateral triangle, and the outer surface of each side is pasted with an abrasive belt made of wear-resistant steel, so that good contact between the abrasive belt and the rotor is ensured.
The wire guide mechanism 5 comprises a bearing fixing plate 52, a wire inlet guide plate 51 and a wire outlet guide plate 53; the wire inlet guide plate 51 and the wire outlet guide plate 53 are arranged on the frame 1, and the bearing fixing plate 52 is arranged on the wire inlet guide plate 51 and the wire outlet guide plate 53 and is positioned between the two.
The tension adjusting mechanism 6 comprises a pulley seat 61, two pulleys 63, a pulley shaft 62 and an adjusting nut 64, wherein the pulley shaft 62 is arranged on the pulley seat 61, the two pulleys 63 are respectively arranged on two sides of the pulley shaft 62, the adjusting nut 64 is arranged on the pulley 63, and the adjusting nut fixes the leg wire at different positions of the pulley according to the size of the required tensile load, and the two groups of pulleys complete the leg wire test of the electric detonator at each time.
One end of a detonator leg wire is fixed on a leg wire fixing nut 22 connected with the gravity sensor 21, the other end of the detonator leg wire horizontally places the detonator leg wire at a test initial position in parallel through an incoming wire guide plate 51, then passes through an outgoing wire guide plate 53, is fixed through a pulley 62, passes through an adjusting nut 64 and is finally connected with a weight.
Adjusting the position of the rotor 42 to the initial position shown in fig. 1, lifting the hinge arm 32 to a certain height from the center of the rotor, and then fixing the hinge arm 32 at the above position; adjusting the position of the adjusting nut 64 to a specified load; the pivot lever 32 applies a load to the detonator leg wire through the weight lever 33 and the weight 34 placed thereon, and the rotor 42 is activated, and the rotor 42 should be able to automatically stop rotating if the leg wire insulation is worn through (by detecting whether the leg wire core wire is in electrical contact with the abrasive belt or the rotor). The controller records the time from the beginning of the test to the occurrence of the fault (i.e. the insulating layer of the leg wire is worn through), thereby completing the test of the wear resistance of the detonator leg wire.
The testing method of the electric detonator leg wire wear resistance testing device comprises the following steps:
s1, performing a test under a predetermined temperature condition;
s2, adjusting the rotor position to the initial position shown in the figure 1;
s3, lifting the pivot rod to a certain height from the center of the rotor, and fixing the pivot rod at the position;
s4, fixing one end of the detonator leg wire on the tension measuring mechanism through the leg wire fixing nut, as shown in figure 1. If the detonator has two leg wires, the leg wires are not separated, but are horizontally placed at the test starting position in parallel;
s5, adjusting the tensile load to a specified load;
s6, applying different loads to the pivot rod according to different detonator leg wire types (removing the self-adjustable load of the pivot rod);
s7, starting the rotor;
s8, when the pivot rod is lifted by the test piece, the timing device will be triggered automatically;
and S9, if the pin wire insulating layer is worn out (by detecting that the pin wire core wire is in electrical contact with the abrasive belt or the rotor), the rotor automatically stops rotating.
S10, the PLC control system automatically records the time elapsed from the start of the test until failure occurs (i.e., the pin wire insulation is worn through).
The testing device can avoid the over-tightening and breaking of the detonator leg wire in the process of orderly straightening the detonator leg wire before the detonator leg wire enters the host machine, is favorable for the better entering of the leg wire, is favorable for various operations in the testing process, and accurately and reliably realizes the testing of the wear resistance of the detonator leg wire. The device with the related structure is not used for testing the wear resistance of the detonator leg wire, so that the efficiency of testing the wear resistance of the detonator leg wire is improved within a certain range, and the reliability of the device is improved.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention.
Claims (4)
1. A method for testing the wear resistance of a detonator leg wire is characterized by comprising the following steps: the device for testing the wear resistance of the detonator leg wire comprises a rack, a tension measuring mechanism, a wire pressing mechanism, a rotating mechanism, a wire guiding mechanism and a tension adjusting mechanism, wherein the tension measuring mechanism, the wire pressing mechanism, the rotating mechanism, the wire guiding mechanism and the tension adjusting mechanism are arranged on the rack; one end of a detonator leg wire is fixed on a tension measuring mechanism, the other end of the detonator leg wire penetrates through a wire guide mechanism and is fixed by a tension adjusting mechanism, a part to be tested of the detonator leg wire is horizontally placed on a testing starting position between a wire pressing mechanism and a rotating mechanism, the tension measuring mechanism comprises a gravity sensor, a leg wire fixing nut, the gravity sensor is installed on a rack, the leg wire fixing nut is installed on the gravity sensor and is used for connecting one end of the tested electric detonator leg wire, and the wire pressing mechanism comprises a pivot rod seat, a pivot rod, a counterweight rod and a counterweight; the pivot rod seat is arranged on the rack, one end of the pivot rod is connected with the pivot rod seat, the other end of the pivot rod is connected with the counterweight rod, and the counterweight is arranged on the counterweight rod; the lower part of the connecting side of the pivot rod and the counterweight rod is provided with an arc grinding head, a load is applied to a tested leg wire through the rod and a weight, and the rotating mechanism comprises a main shaft, a rotor, a sleeve and a motor; the motor is connected with the main shaft, the sleeve is arranged on the main shaft, the rotor is arranged on the sleeve, and the wire guide mechanism comprises a bearing fixing plate, a wire inlet guide plate and a wire outlet guide plate; the tension adjusting mechanism comprises a pulley seat, two pulleys, a pulley shaft and an adjusting nut, wherein the pulley shaft is arranged on the pulley seat, the two pulleys are respectively arranged on two sides of the pulley shaft, the adjusting nut is arranged on the pulley, and the adjusting nut fixes the leg wire at different positions of the pulley according to the size of the required tensile load.
2. The detonator leg wire wear resistance test method of claim 1, wherein: the detonator leg wire wear-resisting property testing device further comprises a PLC control system, and the PLC control system controls the components to start and stop according to a logic sequence.
3. The detonator leg wire wear resistance test method of claim 1, wherein: the rotor is shaped like an equilateral triangle, and the outer surface of each side is pasted with an abrasive belt made of wear-resistant steel, so that good contact between the abrasive belt and the rotor is ensured.
4. The detonator leg wire wear resistance test method of claim 2, wherein: the test of the detonator leg wire wear resistance test device comprises the following steps:
s1, performing a test under a predetermined temperature condition;
s2, adjusting the position of the rotor to the initial position;
s3, lifting the pivot rod to a certain height from the center of the rotor, and then fixing the pivot rod;
s4, fixing one end of the detonator leg wire on a tension measuring mechanism through a leg wire fixing nut, and horizontally placing the leg wire at a test initial position in parallel;
s5, adjusting the tensile load to a specified load;
s6, applying different loads to the pivot rod according to different detonator leg wire types, and removing the self-adjustable load of the pivot rod;
s7, starting the rotor;
s8, when the pivot rod is lifted by the test piece, the timing device is automatically triggered;
s9, if the insulation layer of the leg wire is worn, the rotor automatically stops rotating by detecting that the leg wire core wire is electrically contacted with the abrasive belt or the rotor;
s10, the PLC control system automatically records the time from the test to the time when the insulating layer of the pin wire is worn through.
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| CN201811558848.0A CN109406325B (en) | 2018-12-19 | 2018-12-19 | Method for testing wear resistance of electric detonator leg wire |
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| CN201811558848.0A CN109406325B (en) | 2018-12-19 | 2018-12-19 | Method for testing wear resistance of electric detonator leg wire |
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| CN109406325B true CN109406325B (en) | 2021-04-20 |
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2300601A1 (en) * | 1999-03-31 | 2000-09-30 | Exponent, Inc. | Method and apparatus for determining the true stress and true strain behavior of a ductile polymer |
| CN1828264A (en) * | 2006-04-18 | 2006-09-06 | 燕山大学 | On-line measuring and testing machine for radial sliding bearing friction and wearing |
| CN101303285A (en) * | 2008-07-09 | 2008-11-12 | 中国科学院力学研究所 | Stretching strain frictional wear test method and test machine thereof |
| CN101556238A (en) * | 2009-05-11 | 2009-10-14 | 中国船舶重工集团公司第七二五研究所 | Device and method for testing linear reciprocating sliding friction and abrasion |
| CN102507357A (en) * | 2011-10-24 | 2012-06-20 | 温州意华通讯接插件有限公司 | Plating surface wear resistance tester |
| CN103207123A (en) * | 2012-01-11 | 2013-07-17 | 住友电装株式会社 | Method of testing wear resistance of wire covering material |
| CN204086048U (en) * | 2014-10-14 | 2015-01-07 | 江苏省优联检测技术服务有限公司 | A kind of cable roller pressure durable test device |
| CN104374805A (en) * | 2013-08-15 | 2015-02-25 | 中国石油天然气集团公司 | Conductive characteristic-based coating wear resistance testing apparatus and testing method thereof |
| CN206146769U (en) * | 2016-11-07 | 2017-05-03 | 红河学院 | Reciprocating type friction wear testing machine |
| CN107271306A (en) * | 2017-07-27 | 2017-10-20 | 西南科技大学 | It is a kind of to carry drawing, the friction-wear detecting apparatus of press mechanism and method of testing |
| CN107870135A (en) * | 2017-12-13 | 2018-04-03 | 西华大学 | The cable life test device and method of testing of a kind of variable element |
-
2018
- 2018-12-19 CN CN201811558848.0A patent/CN109406325B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2300601A1 (en) * | 1999-03-31 | 2000-09-30 | Exponent, Inc. | Method and apparatus for determining the true stress and true strain behavior of a ductile polymer |
| CN1828264A (en) * | 2006-04-18 | 2006-09-06 | 燕山大学 | On-line measuring and testing machine for radial sliding bearing friction and wearing |
| CN101303285A (en) * | 2008-07-09 | 2008-11-12 | 中国科学院力学研究所 | Stretching strain frictional wear test method and test machine thereof |
| CN101556238A (en) * | 2009-05-11 | 2009-10-14 | 中国船舶重工集团公司第七二五研究所 | Device and method for testing linear reciprocating sliding friction and abrasion |
| CN102507357A (en) * | 2011-10-24 | 2012-06-20 | 温州意华通讯接插件有限公司 | Plating surface wear resistance tester |
| CN103207123A (en) * | 2012-01-11 | 2013-07-17 | 住友电装株式会社 | Method of testing wear resistance of wire covering material |
| CN104374805A (en) * | 2013-08-15 | 2015-02-25 | 中国石油天然气集团公司 | Conductive characteristic-based coating wear resistance testing apparatus and testing method thereof |
| CN204086048U (en) * | 2014-10-14 | 2015-01-07 | 江苏省优联检测技术服务有限公司 | A kind of cable roller pressure durable test device |
| CN206146769U (en) * | 2016-11-07 | 2017-05-03 | 红河学院 | Reciprocating type friction wear testing machine |
| CN107271306A (en) * | 2017-07-27 | 2017-10-20 | 西南科技大学 | It is a kind of to carry drawing, the friction-wear detecting apparatus of press mechanism and method of testing |
| CN107870135A (en) * | 2017-12-13 | 2018-04-03 | 西华大学 | The cable life test device and method of testing of a kind of variable element |
Non-Patent Citations (2)
| Title |
|---|
| 工业电雷管国标与国外先进标准的比较;肖月华等;《爆破器材》;20050228;15-16 * |
| 电雷管脚线成型工艺设备现状与发展趋势;杨民刚;《煤矿爆破》;20141231;6-14 * |
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