53results about How to "Small insulation resistance" patented technology

The improved oil resistant semi-conductive cable shielding material consists of butadiene-acrylonitrile rubber or hydrogenated butadiene-acrylonitrile rubber 100 weight portions, conducting carbon black 50-80 weight portions, graphite powder 15-30 weight portions, plasticizer 15-20 weight portions, dithio tetramethyl thiram and alphatic polysulfide 1.0-3.0 weight portions, dibenzothiazole disulfide and zinc diethyl dithio amino formate 1.0-2.0 weight portions, zinc oxide and stearic acid 8.0-10.0 weight portions. Compared with available technology, the present invention has the advantages of excellent conductivity, volume resistivity not greater than 50 ohm.cm, high tensile strength up to 18 MPa, high oil resistance and other advantages.

The invention provides a prefab branch cable and a production method thereof. Both a backbone cable and a branch cable consist of a conductor, an insulating layer and a metal sheath, wherein, the insulating layer is wound by a mineral insulated tape, wires of both the backbone cable and the branch cable are connected in a Y shape, the mineral insulated tape is wound outside nodes and compression jointed together by a connecting piece, the outermost layer is sealed by a metal encloser and a metal cap which are fitted, both the metal enclosure and the metal cap are provided with corresponding connecting holes and are fixedly connected by a fastening piece. The high-temperature resistance, the humidity resistance and the fire resistance or the sealing effect of the prefab branch cable are further improved. The invention has the characteristics of simple end processing structure, safety and reliability, convenient assembly and disassembly, firm cable clamp, good leak tightness, high-temperature resistance, corrosion resistance, fire resistance and explosion prevention; moreover, the invention does not reduce the insulating resistance due to moisture. In the power transmission, the invention can bear greater current capacitance; in case of fire, any smoke or toxic or harmful gases is not generated and the combustion is not caused. Therefore, the invention can be applicable to various industries and civil buildings.

This invention relates to a method for testing leakage of supplying pipelines of non-conduction materials, which sets many connected electrodes in walls of pipelines of different regions of non-conducting materials buried away from ordinary metal pipelines as one pole of conduction and sets many electrodes to be connected one by one outside of the pipeline walls of different regions as the other pole, thus, ordinarily, leakage does not happen and the resistance between electrodes inside and outside of the pipe is large, the device does not alarm at the time, when leakage happens, water infiltrates into the earth and resistance of the electrodes buried in the earth reduces greatly and the device alarms because of small resistance.

Disclosed is a flame-retardant resin composition containing 60-320 parts by mass of a magnesium hydroxide (B) per 100 parts by mass of a resin component (A) which contains 50-100% by mass of an ethylene copolymer (a), 0-50% by mass of an acrylic rubber (b) and 0-30% by mass of a modified polyolefin resin (c) which is modified with an unsaturated carboxylic acid or a derivative thereof. The magnesium hydroxide (B) contains 5-320 parts by mass of a magnesium hydroxide (B-1), which has an aspect ratio of 6-25 and a BET specific surface area of 8-25 m2/g, per 100 parts by mass of the resin component (A).

To provide a flux composition and a solder paste which can suppress decrease in the insulation resistance of flux residues without reducing in an amount of blended activator. A flux composition comprises (A) rosin-based resin, (B) solvent, (C) activator and (D) thixotropic agent, the thixotropic agent (D) comprising a thixotropic agent having (D-1) fatty acid polyamide structure, with the fatty acid having a C12-22 long-chain alkyl group.

A printed wiring board comprises a wiring substrate provided with at least one conductor circuit, a solder resist layer provided on the surface of the wiring substrate, at least one conductor pad formed from a part of the conductor circuit exposed from an opening provided in the solder resist layer, and at least one solder bump for mounting electronic parts on the conductor pad. In the printed wiring board, since the at least one conductor pad is aligned at a pitch of 200 µm or less, and a ratio (W/D) of a diameter W of the solder bump to an opening diameter D of the opening formed in the solder resist layer is within a range of 1.05 to 1.7, connection reliability and insulation reliability can be easily improved.

The invention discloses a numerical control drilling machine for punching the surface of a mechanical part. The numerical control drilling machine comprises drilling machine bases, the tops of the drilling machine bases are fixedly sleeved with fastening connecting frames, the tops of the fastening connecting frames are fixedly sleeved with connecting supporting columns, and the middles of the outer surfaces of the connecting supporting columns are fixedly sleeved with mounting fixing frames. A drilling tool sliding frame is fixedly installed on one sides of the mounting fixing frames, the middle of the drilling tool sliding frame is fixedly sleeved with a sliding inner rack, the middle of the outer surface of the sliding inner rack is movably sleeved with a sliding connecting box, and a machining table is fixedly installed on one side of the drilling machine bases. When a part is drilled by the numerical control drilling machine, clamping force is improved, so that the mechanical part is fixed, clamping arm pressing feet are contracted while the clamping force is improved, the inner surfaces of the clamping arm pressing feet make friction contact with the outer surfaces of drilling tools, the rotating speed of the drilling tools is reduced through friction force, centripetal force of the drilling tools is reduced, the drilling tools are prevented from loosening, the phenomena of slipping and breaking of the drilling tools are avoided, and potential safety hazards are reduced.

The invention provides an outgoing line sealing structure of a transformer oil pump, belongs to the technical field of transformer oil pump sealing and solves the problem of an existing transformer oil pump that the sealing effect is poor. The outgoing line sealing structure of the transformer oil pump is characterized in that the transformer oil pump comprises pump body, a wiring hole is formed in the pump body, an external positioning block is arranged at the outer side of the pump body, and an internal positioning block is arranged at the inner side of the pump body; the internal positioning block, the external positioning block, a conductive rod and the pump body are fixedly connected with a fastener, a first sealing ring is arranged between the external positioning block and the pump body, and a second sealing ring is arranged between the external positioning block and the conductive rod; an inner end, arranged in the pump body, of the conductive rod is connected with a lead-out line; and the part, close to the inner end of the conductive rod, in the pump body is filled with a pouring sealant, the pouring sealant enables the lead-out line connected with the inner end of the conductive rod to be fixed in the pump body, and the pouring sealant blocks the gaps among the pump body, the internal positioning block, the conductive rod and the lead-out line. The outgoing line sealing structure improves the sealing effect and the safety performance of the transformer oil pump.

The present invention provides a flux which contains a resin having film forming ability, an activator and a solvent and is used when soldering is performed on the printed board to which electroless nickel plating is applied. The flux contains organic acid metallic salt of 0.1-20 wt.% to the total amount of the flux and, the activator is the same organic acid as an organic acid which comprises the organic acid metallic salt or an organic acid which is lower than it in acidity. Thus, the stability of the organic acid metallic salt is increased and high joining strength is maintained for a long term.

The purpose of the present invention is to suppress reduction in insulation resistance between an electrode and a case in an electrically heated catalyst (EHC). The EHC (1) of the present invention is provided with a heating element (3) that is heated by conduction and heats a catalyst; a case (4) that accommodates the heating element; an insulating member (5) that is provided between the heating element (3) and the case (4) and insulates against electricity; an electrode (7) connected to the heating element (3) via an electrode chamber (9) that is a space positioned between an inner wall surface of the case (4) and the outer peripheral surface of the heating element (3); and a ventilation passage (10) that ventilates the electrode chamber.

The invention relates to an electric heating catalyst. The purpose of the present invention is to prevent the decrease in the insulation resistance between an electrode and a case which is usually caused by the action of condensed water in an electric heating catalyst (EHC). This EHC (1) comprises a heating element (3) which can generate heat upon the conduction of an electric power to heat a catalyst, a case (4) which accommodates the heating element, and an insulating member (5) which is arranged between the heating element (3) and the case (4) and insulates an electric power. In the case (4) of the EHC (1), an electrode chamber (9), which is a space formed around an electrode (7) that is connected to the heating element (3), is closed by a closing member (10) which has higher air-tightness than those of the heating element (3) and the insulating member (5).

The invention discloses a high-efficiency cooling waterproof busbar groove specially for power transmission, which comprises a conductor connector insulation sleeve, cooling plates, fixedly-mounted clamping grooves, a branch jack cover plate and a bus clamping groove, wherein the branch jack cover plate is arranged in the middle position on the front surface of a jack insulation separator; connector insulation bolts are embedded inside a sealing plate at the connector side; and the cooling plates are arranged on the upper surface and the lower surface of a waterproof breathable layer. The high-efficiency cooling waterproof busbar groove specially for power transmission has the advantages that the structure is scientific and reasonable; the use is safe and convenient; the operation is simple; the work is quick; the functions are comprehensive; as the cooling plates are arranged when conductors in the bus clamping groove is electrified, much heat is generated, under effects of the cooling plates, heat in the bus clamping groove can be efficiently discharged, the conductor can be cooled quickly, and the conductive effects of the conductor are not influenced; and as the waterproof breathable layer is arranged, the bus is not easily dampened and permeable in the case of construction, and interphase insulation resistance is further not caused to fall.

The invention discloses a manufacturing method of a double-sided photoelectric substrate with interconnected high-density through holes. According to the method, the double-sided interconnected photoelectric ceramic substrate with the high-density micro-through holes is manufactured on the basis of the processes of manufacturing the micro-through holes in the ceramic substrate by a laser processing technology, filling the auxiliary through holes, flattening the surface, sputtering a film layer, manufacturing wiring lines and the like. The method is based on a fine processing technology of AlNceramic by laser. The manufacturing technology of the high-density micro-through-hole interconnection photoelectric device is studied, through the high-density micro-through-hole double-face interconnection technology, the double sides of the substrate are connected via the through holes, Au is filled in the through holes, and the problems that the back face of a photoelectric module device circuit needs to have corresponding functions and is connected with a front face graph and reliability is poor are solved. A metal film layer is prepared on the basis of a magnetron sputtering technology, the high-density micro-through-hole interconnection photoelectric device manufacturing technology is realized, a patterning process technology is carried out through a metallization layer, and a thickfilm hole filling process and a thin film patterning process are effectively combined.

The invention discloses a sand-measuring ionization chamber which comprises an upper end tube and a lower end tube connected by a flange and is separated into two separate parts. The upper end tube isinternally provided with an amplifier plate, a high-voltage power source frame and a temperature sensor, and a high-voltage power source is mounted in the high-voltage power source frame; the lower end tube is internally provided with an electrode container and filled with high-voltage inert gas; the top end of the lower end tube is provided with an aluminum window; a ceramic insulator is weldedon the flange; a lead tube on the electrode container is connected with a high-voltage electrode on the high-voltage power source frame by the ceramic insulator; the other electrode on the high-voltage power source frame is connected with the input end of an amplifying circuit on the amplifier plate; the output end of the amplifying circuit on the amplifier plate is connected with a cable; and theother end of the cable is externally connected with a computer. The sand-measuring ionization chamber improves the efficiency of a 241 Am gamma radioactive source by more than one magnitude, uses theradioactive source with great activity, little Statistical error and good stability, has strong harsh environment toleration, good long-term signal stability, wide measuring range and low failure rate, thereby being suitable for the online measurement of the sediment concentration of underwater silt.