43results about How to "Eliminate the risk of short circuits" patented technology

The invention provides an electrode subassembly, a preparation method thereof and a lithium secondary battery. The electrode subassembly is composed of a positive plate, separating layers and negative plates. The positive plate is a continuous positive plate; the two surfaces of an anode current collector of the positive plate are coated with an anode active material; and the positive plate is folded continuously so as to obtain a Z-shaped vertical section. The two surfaces of a cathode current collector of each negative plate are coated with a cathode active material, and are respectively arranged to be opposite to two positive plate opposite surfaces which are formed because of folding, so that the two negative plate surfaces which are coated with the cathode active material are respectively opposite to the two positive plate surfaces which are formed by folding, but positive plate outer surfaces which are formed by folding are not opposite to the surfaces of the negative plate. Each separating layer is arranged between a surface of the positive plate and a surface of a negative plate, wherein the surface of the positive plate and the surface of the negative plate are arranged oppositely. The positive plate and the negative plates are respectively provided with a contact area used for connection of lead wires. The electrode subassembly is easy for preparation, and is suitable for large-scaled production; materials are fully used; and cost is reduced.

The invention discloses a micro electromechanical resonator based on a structural self-excited vibration principle, which comprises an insulation support pedestal, a conducting micro beam, two direct current driving electrodes and a substrate, wherein the insulation support pedestal is neither connected with any electrode nor grounded, that is electric potential is floating; one end of the conducting micro beam is fixed on the insulation support pedestal; the other end of the conducting micro beam is horizontally overhung; the two direct current driving electrodes are placed on the two sides of the conducting micro beam; one of the direct current driving electrodes is connected into direct current positive voltage; the other direct current driving electrode is connected into direct current negative voltage; a certain distance is kept between the two direct current driving electrodes; and the insulation support pedestal and the direct current driving electrodes are fixed on the substrate. The micro electromechanical resonator abandons a complicated alternating current driving / detection circuit essential to the traditional resonator, and eliminates a short circuit risk arising from structure destabilization; a structure is simplified; and resonance amplitude is increased greatly.

The invention discloses a non-contact liquid cooling system for high-power charging and a liquid cooling method of the non-contact liquid cooling system, the non-contact liquid cooling system comprises a liquid cooling cable, a cable built-in pipeline is arranged in the center of the liquid cooling cable, a quick connector is arranged at the rear end of the cable built-in pipeline, and the cable built-in pipeline is coated with a cable conductor. A cable outer insulating layer is arranged on the outer side of the cable conductor, a power terminal is connected to the rear end of the cable conductor in a pressing mode, the quick connector is fixedly installed on a liquid cooling cavity, and an insulating heat conduction piece is arranged in the liquid cooling cavity. According to the non-contact liquid cooling system for high-power charging and the liquid cooling method of the non-contact liquid cooling system, heat generated on the power terminals during charging is transmitted to and exchanged to the cooling liquid through the insulating heat conduction piece, the rapid circulating cooling liquid transmits heat, the cooling is rapid, a non-contact mode is adopted, the cooling liquid is safer, the short-circuit risk is eliminated, and through the I-shaped design of the insulating heat conduction piece, the heat dissipation is more comprehensive and effective.

The invention provides a modular multilevel-based STATCOM device for inhibiting ripples of capacitive voltage. The STATCOM device comprises an STATCOM system which is directly connected to a common node through a connection inductor in parallel, wherein the STATCOM system comprises a bridge arm phase A, a bridge arm phase B, a bridge arm phase C and a bridge arm phase D. On the basis of an MMC topology, the DC bus voltage of the MMC is eliminated, the hidden danger of a short circuit of a common bus of a DC side is eliminated and the security of the device is improved; the low-frequency ripples of capacitive voltage of an upper bridge arm and a lower bridge arm of each bridge arm phase are inhibited by using a low-voltage and low-capacity capacitor, so that use of lower capacitance of a sub-module is facilitated, the cost of a system is reduced and the volume of the device is reduced. The bride arm phases of switching devices are replaced with buffer inductors, the quantities of the capacitors and the switching devices are reduced to 3 / 4 of those of a conventional structure, so that the cost and the volume of the device are significantly reduced and the loss of the system is reduced. The application of the bridge arm phase is not limited to the application scene of reactive power compensation and an existing bridge arm phase adopting cascaded H-bridge multilevel topological devices can be replaced.

Disclosed is an embedded type wiring terminal sealing cover for large aluminium electrolytic capacitors, wherein an insulating material which is identical with a terminal cover and integrated with an insulating terminal block is used for coating a naked positive wiring terminal post and a naked negative wiring terminal post respectively or integrally, or the wiring terminal posts are embedded into the insulating material body of the cover, so that the distance between the positive wiring terminal post and the negative wiring terminal post in the insulating material is reduced, the area of a loop is reduced, the equivalent series inductance (ESL) value is reduced, and at the same time, the risk that the positive pole and the negative pole are short-circuited caused by an electrolyte splashed during release of a pressure valve is eliminated.

A heat sink includes a base and at least one spring retainer. A spring is sleeved on the spring retainer; a through hole allowing the spring retainer to pass through is formed on the base; a buckle is arranged in the through hole or nearby the through hole on the base; and the buckle clips at least one spring ring of the spring between the base and the buckle. Compared with the prior art, the invention uses the buckle on the base to replace a retaining ring, reduces cost for retaining ring assembly and materials, and eliminates risk of short-circuited circuit board caused by retaining ring falling off.

The invention relates to a manufacturing method of a lead-acid storage battery negative grid, and the manufacturing method comprises the following steps of a, stretching a copper plate to be reticulate so as to form copper stretch metal, and tailoring the copper stretch metal into a rectangular structure; b, pouring lead alloy on one end of the copper stretch metal to form a lug; c, electroplating lead on the surface of the copper stretch metal with the lug, and forming a lead-plated layer on the surface of the copper stretch metal; and d, carrying out the injection molding on the other end of the width direction and two ends of the length direction of the copper stretch metal to form a plastic frame. By adopting the manufacturing method, after the copper stretch metal is stretched, the operation for curling the frame is not needed; after a copper frame is removed and the molded frame is adopted for the copper stretch metal, no conditioning fluid remains in the lead electroplating process, so that the electroplating quality is guaranteed, and the rejection rate is reduced; and due to the adoption of the plastic frame, the strength of the grid can be guaranteed, the short-circuit potential danger of the negative electrode and the positive electrode can be eliminated, and components such as a frame protection sleeve are not needed.

The invention provides an electrochemical production device of high-alkalization-degree aluminum polychlorid and Al13 chloride. The electrochemical production device comprises a reaction container, a pump, an electrolytic cell stack and a flow rate indicator, which form a closed loop and are sequentially connected with one another, wherein the electrolytic cell stack consists of a plastic partition plate and an electrolytic cell group which are clamped, the electrolytic cell group consists of two inert electrodes which are adjacent to two sides of the plastic partition plate, both the plastic partition plate and each inert electrode are provided with a raw material liquid inlet and a product and half-finished product liquid outlet, respectively, and the inlet is connected with the outlet through a runner which is provided with a turbulence promotion grid. The invention also provides a manufacturing method of the high-alkalization-degree aluminum polychlorid and Al13 chloride by utilizing the production device. By adopting the device and the method, the distance between the electrodes and the polarization in an electrolysis process can be greatly reduced, the voltage loss in the electrolysis process can be reduced, and the energy consumption is reduced; rubber partitions such as aluminum hydroxide can be eliminated, and the aluminum polychlorid with high purity and alkalization degree and even the pure Al13 chloride can be directly produced.

The invention relates to a cooling device for a bearing and a sliding ring of a doubly fed wind driven generator. The device comprises a main shaft, one end of the main shaft penetrates through a bearing installing motor end cover, a wind blocking hood is arranged on the inner side of the motor end cover, a wind blocking hood cavity is formed in the part between the wind blocking shield and the motor end cover, a wind blocking hood cavity inlet and a wind blocking hood cavity outlet are formed in the end face of the motor end cover, the wind blocking hood cavity outlet is communicated with a sliding ring chamber through a wind induction pipe, and a ventilation fan is installed on the outer side wall of the sliding ring chamber; the sliding ring and a carbon brush are installed at one end of the main shaft and embedded in the sliding ring chamber; a sliding ring chamber first air inlet and a sliding ring chamber second air inlet are formed in the side wall of the sliding ring chamber. The structure of the cooling device is simple, the problem of excessively high temperature during the operation process of a bearing on the side of a shaft band centrifugal fan of the doubly fed wind driven generator resulting in the locking of the bearing and the reduction of the service life of the bearing is solved, the cooling effect on the sliding ring and the carbon brush can be ensured, carbon powder in the sliding ring chamber does not easily accumulate, and the problem of the short circuit of the sliding ring and the carbon brush due to the fact that the carbon powder is not dischargedsmoothly is solved.

The invention discloses a filter with an adjustable inner space for a filter pool. The filter with the adjustable inner space for the filter pool is characterized in that the filter is a filter for the filter pool, and according to the filter, the inner space size is adjustable, and a filter material can be subjected to rolling cleaning. The filter comprises an arc-shaped grid mesh cover capable of folding, pressing, opening and loosening the filter material on the upper part, a pneumatic pressing and fixing device on the top, a semicircular horizontal cylindrical main body for placing the filter material in the middle, a porous water outlet plate on the lower part, a water collection tank at the bottom, a water outlet pipe and a backwash water inlet device, wherein a stirrer is arranged on a center shaft of the filter, and a cylinder wall plate and a bracket are arranged at two ends of the filter; a mechanical device assembly which drives the arc-shaped grid mesh cover to fold and unfold by virtue of a cylinder, a gear and a rack is arranged at one end of the center shaft; a mechanical device assembly which drives the center shaft and the stirrer to rotate so as to perform rolling cleaning on the filter material by virtue of a motor is arranged at the other end of the center shaft; the stirrer is connected with an air compression conveyer unit; and the filter is arranged in the filter pool, and the water is filtered.

The invention discloses an electrostatic generation device and an electrostatic dust remover. The electrostatic generation device comprises multiple anode needles for discharging; the anode needles are mounted in mounting holes, and needle points are downwards; and cathode plates are arranged around the needle points of the multiple anode needles, so that each anode needle is positioned in independent space. The anode needles are connected with a positive pole of a power supply; and the cathode plates are connected with a negative pole of the power supply. A lot of positive and negative charges are generated in the discharging process of the anode needles; and the charges are combined with dust particles in air currents. Meanwhile, in the discharging process, cell walls of bacteria can bebroken through to achieve a sterilization effect. The electrostatic dust remover comprises a dust collecting device and the electrostatic generation device; the dust collecting device comprises multiple dust collecting units arranged rightly above the electrostatic generation device from top to bottom; the dust collecting units comprise frames; and multiple dust collecting plates vertically arranged in parallel are arranged in the frames. The multiple dust collecting units can be provided for widening the absorbing range.

The invention provides a broken-line etching design method of a soft printed circuit board electroplating lead, comprising the following steps: (1) previously opening a broken-line hole on a solder mask layer, keeping the position of the broken-line hole corresponding to the position of the electroplating lead which requires to be broken on a circuit layer so as to expose the electroplating lead which requires to be broken out of the broken-line hole; (2) fully covering the broken-line hole with a film made of a plating-proof medium, and performing electroplating treatment on the position of a circuit board in need of electroplating; (3) removing the film made of the plating-proof medium at the position of the broken-line holes after electroplating treatment so as to expose the electroplating lead out of the broken-line hole; (4) covering the part of the circuit board besides the broken-line hole by the film made of the plating-proof medium so as to expose the electroplating lead out of the broken-line hole; and (5) removing the electroplating lead exposed in the broken-line hole by an etching method so as to disconnect the electroplating lead. For the circuit board made by the method, cabling on other layers is not affected by the broken-line hole, and short-circuit hidden trouble does not occur.

The invention provides a graphene quantum dot modified electrolyte and a preparation method thereof, and belongs to the field of lithium metal battery electrolytes. By adding graphene quantum dots anda polymer in the commercial electrolyte, the graphene quantum dots can continuously provide nucleation sites, and the polymer enables uniform dispersion of the graphene quantum dots in the electrolyte, thereby obtaining simple process and obviously improving cycling and multiplying performance of lithium metal batteries under operating conditions of high current and high capacity. When the lithium metal batteries in the graphene quantum dot modified electrolyte have a current density reaching 4mA / cm2 and a cycling capacity reaching 4mAh / cm2, there is still no short circuit caused by lithium dendrites, and good charging and discharging performance is kept, thereby having potential application in the field of lithium metal batteries, and realizing the purpose of lithium negative protectionunder high current and high capacity.

The invention relates to a fixing device combination, comprising a substrate and at least one spring fastener. Each spring fastener comprises a body and a spring sleeved on the body; a pressing portion is formed at one end of the body; a buckling portion is formed at the other end of the body opposite to the pressing portion, the body further comprises a slender rod portion between the pressing portion and the buckling portion; the substrate is provided with at least one mounting groove communicating with the substrate, an opening is formed at the outer side of the mounting groove; the width of the mounting groove is less than the outer diameter of the buckling portion but is not less than the outer diameter of the slender rod portion; the slender rod portion is clamped in the mounting groove from the opening; the buckling portion is located below the mounting groove and supports against the lower side of the mounting groove; at least one stopping portion is formed in the position where the substrate is adjacent to the mounting groove and supports against the spring fastener to prevent the spring fastener from dropping from the opening of the mounting groove.

The invention discloses an oil-resistant drag chain wire, and the wire comprises a plurality of core wire layers; each core wire layer comprises a Kevlar wire inner layer, a conductor and an insulating layer; the Kevlar wire inner layer is arranged in the center of the conductor, the conductor is tightly coated on the outer surface layer of the Kevlar wire inner layer, and the insulating layer istightly coated on the outer side of the conductor. The plurality of core wire layers are annularly arranged, a Kevlar wire central layer is arranged in the center of the annular arrangement of the plurality of core wire layers, and the outer sides of the plurality of core wire layers are tightly coated with an outer coating layer; according to the drag chain wire, a plurality of machine tool corewires in the prior art are directly compounded into one wire and separated through the insulating layer, only one wire harness needs to be fixed in a machine tool, and the problems that due to the fact that multiple existing machine tool wire harnesses need to be tightly bound together, a cable insulating layer is often damaged to a certain extent due to tight binding, and equipment often operatesin an overload mode, the cable is scrapped in advance due to excessive use or bad use when the cable does not reach the expected service life value is solved.

The invention discloses an array type positive electrode current collector for a liquid metal battery. By arranging a columnar array pointing to the direction of a negative electrode at the bottom ofa positive electrode current collector shell, the distribution uniformity of the positive electrode interface of the liquid metal battery is effectively improved, the internal stress of an interface alloy layer is reduced, more attachment sites are provided for the alloy layer, and the short-circuit risk in the operation process of a large-size battery is effectively eliminated, at the same time,the mass transfer process of the battery charging and discharging process can be effectively ensured, and the safe, stable and efficient battery operation is promoted.

The invention discloses a wall-hanging fresh air fan which comprises a shell. A fresh air port communicating with the outdoor, an air return port, and an air outlet are formed in the shell; the air return port and the air outlet communicate with the indoor; a fresh air fan, an air return fan and an air outlet fan are arranged on the fresh air port, the air return port and the air outlet; and onlyone of the air return port and the fresh air port can be opened at the same time. The wall-hanging fresh air fan further comprises an electrostatic precipitation device and a heat accumulator carryingout heat exchange with an air flow, wherein the electrostatic precipitation device and the heat accumulator are arranged in the shell. According to the wall-hanging fresh air fan with the structure,the heat accumulator is utilized for balancing the temperature difference between fresh air and indoor air so as to discharge air, so that the use comfort of the fresh air fan is greatly improved.

The invention relates to the design field of a circuit, and particularly relates to an automatic mounting and tin block addition-based through hole reflow soldering. By applying automatic mounting andtin block addition-based through hole reflow soldering, a tin block material is loaded by a braided band, so that automatic material taking and tin block mounting and adding are realized; and the problems of less tin and poor soldering caused by the generated tin balls in the through hole reflow soldering are solved, reliability of through hole reflow soldering is improved, the processing qualityof a PCBA board is improved, the repair cost in manpower tin-supplementing soldering is lowered, and the hidden risk of short circuit caused by tin ball residue is eliminated.

The invention provides a lithium ion battery negative electrode packaged integrally by using diaphragm paper through coating and hot melting. The lithium ion battery negative electrode comprises a lithium ion battery negative electrode piece, wherein the negative electrode piece is coated by two layers of diaphragm paper which is slightly larger than the negative electrode piece, and hot-molten around the diaphragm paper, and the diaphragm paper and the negative electrode piece are packaged integrally to form the lithium ion battery negative electrode, and an opening is formed in one end head of the lithium ion battery negative electrode packaged integrally and is positioned in one side of the diaphragm paper. According to the lithium ion battery negative electrode, the negative electrode piece is completely coated by adopting the diaphragm paper, and hot-molten around the diaphragm paper, the negative electrode piece and the diaphragm paper are packaged integrally to form the lithium ion battery negative electrode; then the lithium ion battery negative electrode and a positive electrode pole piece are coiled to form a battery cell. Because the negative electrode piece is coated by the diaphragm paper, and then is hot-molten and packaged, the battery cell is not in contact with the positive electrode pole piece when being coiled, so that the short circuit hidden danger inside the battery cell is eliminated, and the safety and reliability of the battery are improved. The lithium ion battery negative electrode has a good popularization and reference function to the manufacture of similar lithium ion battery cells.

The invention provides a permanent magnet motor comprising an angle detection device. The permanent magnet motor comprises a permanent magnet motor body and a rotation angle detection device, whereinthe permanent magnet motor body comprises a motor stator and a permanent magnet rotor; magnetic poles of the permanent magnet rotor are alternately distributed along the circumferential direction; therotation angle detection device comprises a stator and a rotor; the permanent magnet rotor and the rotor are installed on the same shaft and rotate coaxially; the stator comprises a stator yoke and stator detection teeth located on the stator yoke; at most one coil is wound on each stator detection tooth; the inductance of each coil changes along with the change of the rotation angle of the rotorso as to be used for detecting the rotation angle of the rotor. The reliability of the permanent magnet motor is greatly improved.

The invention discloses a power signal wall through connecting device avoiding short circuit. The power signal wall through connecting device comprises a circuit board, an insulator and a connecting line, wherein a small hole is formed on the circuit board, the insulator is inserted in the small hole on the circuit board, and the connecting line passes through the insulator and is in welding connection with the circuit board. By the power signal wall through connecting device disclosed by the invention, the board is convenient to install and uninstall, and a hidden hazard that a circuit which is externally connected with the insulator and the shell of the insulator is shorted out is eliminated; simultaneously, influences of thermal expansion contraction on a welding part also can be reduced, and the power signal wall through connecting device is convenient to operate and has good practicability.

The invention discloses a filter with an adjustable inner space for a filter pool. The filter with the adjustable inner space for the filter pool is characterized in that the filter is a filter for the filter pool, and according to the filter, the inner space size is adjustable, and a filter material can be subjected to rolling cleaning. The filter comprises an arc-shaped grid mesh cover capable of folding, pressing, opening and loosening the filter material on the upper part, a pneumatic pressing and fixing device on the top, a semicircular horizontal cylindrical main body for placing the filter material in the middle, a porous water outlet plate on the lower part, a water collection tank at the bottom, a water outlet pipe and a backwash water inlet device, wherein a stirrer is arranged on a center shaft of the filter, and a cylinder wall plate and a bracket are arranged at two ends of the filter; a mechanical device assembly which drives the arc-shaped grid mesh cover to fold and unfold by virtue of a cylinder, a gear and a rack is arranged at one end of the center shaft; a mechanical device assembly which drives the center shaft and the stirrer to rotate so as to perform rolling cleaning on the filter material by virtue of a motor is arranged at the other end of the center shaft; the stirrer is connected with an air compression conveyer unit; and the filter is arranged in the filter pool, and the water is filtered.

The invention provides a broken-line etching design method of a soft printed circuit board electroplating lead, comprising the following steps: (1) previously opening a broken-line hole on a solder mask layer, keeping the position of the broken-line hole corresponding to the position of the electroplating lead which requires to be broken on a circuit layer so as to expose the electroplating lead which requires to be broken out of the broken-line hole; (2) fully covering the broken-line hole with a film made of a plating-proof medium, and performing electroplating treatment on the position of a circuit board in need of electroplating; (3) removing the film made of the plating-proof medium at the position of the broken-line holes after electroplating treatment so as to expose the electroplating lead out of the broken-line hole; (4) covering the part of the circuit board besides the broken-line hole by the film made of the plating-proof medium so as to expose the electroplating lead out of the broken-line hole; and (5) removing the electroplating lead exposed in the broken-line hole by an etching method so as to disconnect the electroplating lead. For the circuit board made by the method, cabling on other layers is not affected by the broken-line hole, and short-circuit hidden trouble does not occur.

The invention provides a modular multilevel-based STATCOM device for inhibiting ripples of capacitive voltage. The STATCOM device comprises an STATCOM system which is directly connected to a common node through a connection inductor in parallel, wherein the STATCOM system comprises a bridge arm phase A, a bridge arm phase B, a bridge arm phase C and a bridge arm phase D. On the basis of an MMC topology, the DC bus voltage of the MMC is eliminated, the hidden danger of a short circuit of a common bus of a DC side is eliminated and the security of the device is improved; the low-frequency ripples of capacitive voltage of an upper bridge arm and a lower bridge arm of each bridge arm phase are inhibited by using a low-voltage and low-capacity capacitor, so that use of lower capacitance of a sub-module is facilitated, the cost of a system is reduced and the volume of the device is reduced. The bride arm phases of switching devices are replaced with buffer inductors, the quantities of the capacitors and the switching devices are reduced to 3 / 4 of those of a conventional structure, so that the cost and the volume of the device are significantly reduced and the loss of the system is reduced. The application of the bridge arm phase is not limited to the application scene of reactive power compensation and an existing bridge arm phase adopting cascaded H-bridge multilevel topological devices can be replaced.

The invention relates to an anti-collision device for cart traveling mechanisms of a ship unloader and a control method. The anti-collision device for the cart traveling mechanisms of the ship unloader comprises a distance measuring module, an image module and a main controller. The distance measuring module comprises a distance displayer and a plurality of distance measuring sensors; the distance displayer is installed in a cab, and the distance measuring sensors are installed on the front sides and the rear sides of all the cart travelling mechanisms; the image module comprises an image displayer and a plurality of image sensors, the image displayer is installed in the cab, and the image sensors are installed on the front side and the rear side of all the cart travelling mechanisms; and the main controller is in communication connection with the distance displayer, the distance measuring sensors, the image displayer and the image sensors. Compared with the prior art, the real-time distance between the cart travelling mechanisms and the obstacle is obtained through the distance measuring module, real-time images of the cart travelling mechanisms are obtained through the image sensors, and a visual blind area is eliminated, so that collision prevention is achieved, and the digitization and visualization degree is higher; and hidden dangers of poor contact and a short circuit of an existing limiting column-travel switch structure are eliminated.

The invention relates to a manufacturing method of a lead-acid storage battery negative grid, and the manufacturing method comprises the following steps of a, stretching a copper plate to be reticulate so as to form copper stretch metal, and tailoring the copper stretch metal into a rectangular structure; b, pouring lead alloy on one end of the copper stretch metal to form a lug; c, electroplating lead on the surface of the copper stretch metal with the lug, and forming a lead-plated layer on the surface of the copper stretch metal; and d, carrying out the injection molding on the other end of the width direction and two ends of the length direction of the copper stretch metal to form a plastic frame. By adopting the manufacturing method, after the copper stretch metal is stretched, the operation for curling the frame is not needed; after a copper frame is removed and the molded frame is adopted for the copper stretch metal, no conditioning fluid remains in the lead electroplating process, so that the electroplating quality is guaranteed, and the rejection rate is reduced; and due to the adoption of the plastic frame, the strength of the grid can be guaranteed, the short-circuit potential danger of the negative electrode and the positive electrode can be eliminated, and components such as a frame protection sleeve are not needed.

The invention provides a PCBA needle bed testing machine and a testing method, and the testing method proposes the feasibility of leading out a part of testing signals to a testing device in other dimensions by reducing the density or number of testing points in a single dimension. According to the PCBA needle bed testing machine provided by the invention, the testing machine comprises a horizontal testing assembly and a vertical testing assembly, the horizontal testing assembly is used for testing a tested card in the horizontal dimension by the testing machine, and the vertical testing assembly is used for testing the tested card in the vertical dimension by the testing machine. According to the invention, the existing tested card terminal on the board card is used as a test interface of another dimension, so that additional test points are not needed when the PCB is designed, and the number of the test points of the needle bed of the test equipment and the processing difficulty are reduced. The technical scheme is low in cost, high in safety coefficient, rapid and efficient.

The invention relates to the technical field of pipe connection and discloses a combined electrofusion connecting pipe. The combined electrofusion connecting pipe comprises an electrofusion connectingpart used for pipe welding. The two ends of the electrofusion connecting part are internally provided with cylindrical electrofusion elements. The electrofusion elements and the electrofusion connecting part are detachably combined and assembled. Through the combined electrofusion connecting pipe, the purpose of manufacturing and mass production of electrofusion connecting pipes can be achieved conveniently. Through detachable combined assembly of the electrofusion connecting part and the electrofusion elements in the electrofusion connecting pipe, the electrofusion connecting part and the electrofusion elements can be manufactured respectively and then are assembled together. The problems that the product rejection rate is high, the required operation level is high, the productivity is low, the labor intensity is large and existing electrofusion connecting pipes are inconvenient to manufacture actually and produce in batches due to the injection molding process adopted for electric heating wires and electric heating connecting parts are solved.