Instruction and Expertise for Usage of TEX-E
Transcription
Instruction and Expertise for Usage of TEX-E
The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. Technical Brochure No. 5749 Issued: May 5, 1997 Revised: Oct 6, 2003 Instruction and Expertise for Usage of TEX-E This is a technical brochure describing instructions and expertise for usage of TEX-E. It should be noted that this brochure does not contain specifications for TEX-E, nor does its description guarantee the performance of TEX-E. The optimum using conditions for TEX-E changes, application by application, depending on the users' process design and processing conditions. Users are requested to make the best use of TEX-E, referring to this brochure. Contents 1. Storage P.1 2. Service Environment P.2 3. Winding Method P.2 3.1 Winding Tension P.3 3.2 Instructions for Winding P.3 4. Soldering P.3 4.1 Soldering Mechanism of TEX-E P.3 4.2. Use of Still-Solder Bath P.4 4.3 Use of Flow-Solder Bath with Cooling Air Blow P.5 4.4 Hint on Bobbin Shape P.7 4.5 Removal of Insulation on the Conductor P.7 4.6 Other Instructions for Soldering P.9 Appendix A Manufacturing tips against physical stresses P.11 1. Storage TEX-E should be stored avoiding high humidity, high temperature, sunshine, and dust. Check before use its withstand voltage, break-down voltage, flexibility, if its storage exceeds the time limit. The following storage conditions are recommended: Temperature : -25 up to 45 Humidity : 5 up to 75% Storage Term : 1 year after shipment 1 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. 2. Service Environment The performance of TEX-E may be degraded by adverse design of its application, severe processing conditions, or harsh service environment of the product. The following service environment, in particular, may hostility affect the performance of TEX-E, so that its adaptability should be confirmed beforehand: (1) Alkaline atmosphere (2) Hermetic condition with high temperature, high humidity and high pressure It must avoid to use TEX-E in the condition which are together with above each factors. (3) Varnish impregnation (4) Detergent When TEX-E is used under a working voltage exceeding its partial discharge inception voltage, its insulation is attacked by partial discharge. In this case, the product employing TEX-E should be provided additional insulation between primary and secondary coil. The partial discharge inception voltage of twist pair, TEX-E and TEX-E/2-UEW is as follows: At power frequency 50Hz, at room temperature, TEX-E / TEX-E : approximately 1.4kVp TEX-E / 2-UEW : approximately 1.0kVp 3. Winding Method The insulation layers of TEX-E are prepared to function appropriately as reinforced insulation stipulated by safety regulations. If the surface layers are excessively deformed or damaged by external stresses, the insulation deteriorates and its function as reinforced insulation may no longer satisfy the requirements stipulated by safety regulations. Thus, excessive external stresses on the insulation layer, whether they are mechanical or thermal, should be avoided as far as possible. Figure 1 Recommended winding tension vs. wire size for TEX-E 2 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. 3.1 Winding Tension Recommended winding tension for TEX-E is, as shown in Figure 1, 58.8MPa (6kg/ ) or less. 3.2 Instructions for Winding When improperly maintained, the following is likely to cause damage on the insulation of TEX-E, so that they should be carefully checked to be in good conditions. (1) Wire guide nozzle of winding machine: The inner diameter of the wire guide nozzle should be 2 to 3 times of the outer diameter of TEX-E, and its exit end corner should be rounded as large and as smooth as possible. (2) Wire guide and guide pulley of winding machine: The guides should have smooth surfaces, and should be properly maintained to be free from damage, wear, or stiff rotation. (3) Bobbin: The bobbins should have no burrs on the inside and on the flanges. The square barrel bobbin corner where TEX-E touches should have an appropriately large radius of curvature. (4) End of wire: The ends of wire, because they are unexpectedly sharp, should be kept away from the insulation layer of TEX-E to avoid the damage. Appendix A shows manufacturing tips against physical stresses. 4. Soldering TEX-E can be soldered without removing its insulation layers. However, because the layers are made of thermo-plastic resins, its insulation performance may be degraded, if proper care is not taken, when the layer of the portion just above the solder bath deform by the heat emitted by the solder. A soldering bath is suited to solder TEX-E, while it is difficult to solder the wire using a soldering iron. Although the melting temperature for the insulation resin is 260-280 , the temperature for the soldering bath should be 420 or higher, in order to solder within a short time avoiding the melt-up of the insulation layer. Below is given the soldering mechanism of TEX-E and the method to suppress the melt-up of insulation layer. 4.1 Soldering Mechanism of TEX-E Because TEX-E is quite different from such enameled wires as polyurethane wires (UEW) in its materials, construction, and manufacturing process, its soldering mechanism is also different from that of those wires as described below. UEW: When heated by the solder, the polyurethane layer dissolves and the wire is soldered. TEX-E: The insulation layers of TEX-E will not dissolve when heated under regular soldering conditions of temperature and time. Instead, the resin melts and floats off due to difference specific gravity, resin and solder to admit the solder invasion between melted resin and conductor, and the wire is soldered. Because the layers do not dissolve, the melted resin tends to stay at the base of terminal pins. 3 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. Size effects are found in the soldering of TEX-E. The soldering conditions are roughly summarized as follows; they can not be specified uniformly because they change depending on the shape of transformer with different heat capacity and heat emission.Less than 0.4mm in diameter: A high temperature solder (420 or higher) is recommended to solder in a relatively short time. Conventional still-solder baths can be used to effect a soldering with reasonably small insulation layer melt-ups, when the soldering condition is controlled to around 420 for 3sec. Other additional means as described in Sections 4.2 or 4.6 works effectively in many cases. 0.4mm or more in diameter: A high-temperature/long-time soldering is necessary, so that some preventive means as described in Section 4.3 and following is required to suppress large melt-ups. In this connection, the variation of the color of insulation layer compared with the normal portion may be useful in telling whether the layer has suffered an excessive heat or not. The resin does not deteriorate under normal soldering condition, but the change of layer thickness due to the thermal deformation induces irregular diffraction to give dissimilar colors. 4.2 Use of Still-Solder Bath Expertise for using still-solder baths which are usually employed in soldering transformer bobbins will be presented here. This soldering method works well for the wires less than 0.4mm in diameter. (1) Swift motion or shaking of bobbin in the bath Horizontal swift motion or shaking of bobbins in the bath is often effective in shortening the soldering time, suppressing melt-up, and in reducing adhesion of melted resin to the bobbin. (Figure 2) 4 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. (2) Repeated soldering Because the melt-up is caused by dipping the bobbins in the bath for a long time, it can be suppressed by repeated soldering, whereby the dipping with a short time is repeated a few times, that is two or three times. The time of dipping has to be confirmed beforehand not to cause melt-ups; and the time of interruption of soldering, in which the bobbins are kept out of the bath, should be such that the portion of bobbin which was in the bath still keeps the after-heat, while which was not becomes cool enough. 4.3 Use of Flow-Solder Bath with Cooling Air Blow Figure 3 and Photo 1 show the schematic diagram and appearance of the flow-solder bath with cooling air blow, respectively. Using this apparatus, three to four bobbins are soldered together. The soldering method with this apparatus has the following advantages. To add a few hints, the cool air blow may be alternatively replaced by other means such as a metal heat sink which fits the bobbin flange. Figure 3 Schematics of flow solder bath cooling air blow Photo 1 External view of flow solder bath with cooling air blow 5 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. (1) This method suppresses effectively the melt-up of insulation layer, by blowing cool air onto the wire in the lead-out groove of the bobbin flanges, thereby cooling the wire. (2) The flow-solder bath steadily supplies fresh solder of high temperature, so that soldering is carried out in a relatively short time, taking advantage of its efficient heat conduction over still-solder baths. (3) The flow-solder bath has a cleaning effect by washing away the melted resins, so that an excellent appearance of soldering can be obtained. (4) This method may also be applied to other manufacturing processes of troublesome products like conventional transformers where the insulation tape tends to melt easily. Furukawa Electric has invented this method and has already applied for its patent, but Furukawa is ready to grant the users of TEX-E its royalty-free use. If you are interested in the purchase of the apparatus, contact the following for further information: JAPAN UNIX CO.,LTD. Head Office Tel:+81-(0)3-3588-0551 Fax:+81-(0)3-3588-0554 21-25, Akasaka 2-Chome, Minato-ku, Tokyo 107-0052, Japan. E-Mail: jpunixin@muc.biglobe.ne.jp When soldering in flow-solder bath and still-solder bath, the oxides are generated on the surface of molten solder. These oxides, once generated, must be removed to prevent the defective soldering. Anti-oxidizing agent (called "SANTOP" and "TOSCUT") are very effective to attain the anti-oxidizing of molten solder, the elimination of soldering defects and the prevention of discoloration caused by oxidization under the high temperature and long storage after soldering. "SUNTOP" and "TOSCUT" are the metal tablets for anti-oxidizing of molten general Sn-Pb solder and molten Pb-free solder, respectively. If you are interested in the anti-oxidization, please contact the following for further information: MEIWA CHEMICAL IND., LTD Head Office Tel:+81-(0)3-3451-2429 Fax:+81-(0)3-3452-3708 Itagarasu-Kaikan Bldg. 2F, 3-6-7, Shibaura, Minato-ku, Tokyo 108-0023, Japan. 6 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. 4.4 Hints on Bobbin Shape For mass production, it is recommended to use a bobbin exclusively designed for TEX-E so as to make the control of soldering much easier. The exclusive bobbin for TEX-E takes into consideration in its shape design, the marginal length for soldering (Lm) which is the melt-up length of insulation layer expected at soldering, in addition to the creepage distance required by safety regulations, as shown in Figure 4. Moreover, when the flow-solder bath with cooling air blow is employed, a bobbin with grooves on its flange will work effectively. If you are interested in the purchase of the apparatus, please contact the following for further information: TOWA KAGAKU CO.,LTD. Mr. MINORU TAKANO : Maneger Sales Dept. Tel:+81-(0)3-3775-2351 Fax:+81-(0)3-3775-2355 6-4-2, Nishiohi Shinagawa-Ku, Tokyo 140, Japan TAMAGAWA ELECTRIC CO., LTD. Mr. RYOICHI SUZUKI : Executive Director Tel:+81-(0)423-77-6670 Fax:+81-(0)423-78-2756 1289-6, Momura, Inagi-City, Tokyo 206, Japan 4.5 Removal of Insulation Study removal of insulation layer before soldering in the following cases. (1) The marginal length for melt-up is not allowed for in the transformer design. (2) The melt-up of insulation layer is not suppressed enough. (3) Manual removal of insulation is preferred as pre-treatment of wire. (4) Diversified small-quantity production prohibits new facilities or exclusive bobbins. For removal of insulation layer, the undermentioned tool is suited which is based on a thermal and mechanical mechanism of insulation removal. It basically melts and removes 7 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. the insulation, so that it does not damage the surface of conductor. Even when small quantities of insulation remain after removal, high temperature soldering may be used successfully leading to a small melt-up with good appearance within a short soldering time. When it is possible to remove the insulation layer completely, low temperature soldering at about 260 may also be used to have a small melt-up. Conventional wire strippers based on a mechanical mechanism of insulation removal may seriously damage TEX-E, because the wire is designed to have a strong adhesion between conductor and insulation to make it suitable for coil winding. Moreover, since material and construction of TEX-E insulation are quite different from those of conventional enameled wires, suitable chemical removers are not available yet. One of the removers shown in photo 2 is the type of stripping mono wire. The other shown in photo 3 is the type of stripping multiple wires. These two type of removers are having the excellent characteristics to each. Photo 2. Example of wire strippers for TEX-E, HOTWEEZERS(R) Photo 3. Example of multiple type wire strippers for TEX-E, WAKOH WS-3 Further information on HOTWEEZERS(R) shown in Photo 2 and WAKOH WS-3 shown in Photo 3 are available from the following sales agent. ANZEN TRADING CO.,LTD. Tel:+81-(0)3-3584-4277 Fax:+81-(0)3-3585-4417 Akasaka Pioneer Bldg., No.22-17, Akasaka 2-Chome, Minato-ku, Tokyo 107-0052, Japan E-Mail: anzen@hkr.jrnet.ne.jp 8 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. 4.6 Other Instructions for Soldering In addition to the above mentioned information, the following knack may help soldering in reducing the soldering time and in suppressing the melt-ups. (1) The end surface of pin winding wire where the conductor of TEX-E is exposed should show up. Refer to Figure 5, (a), (b), and (c). (2) Wind only one wire onto a single pin. (3) The winding pitch on the pin should be loose. (4) In any case, square pin having sharp edges is better than round pin. With TEX-E, soldering is done as the resin melts and solder enters the opening between melted resin and wire conductor. The following pretreatment will work to ease the entering of solder between melted resin and wire conductor, so that the soldering time is reduced and the melt-up is suppressed. (1) Scratch the insulation layer down to the surface of conductor and enlarge the bare portion of conductor. (Figure6) (2) Loosen the wrapping pitch of wire onto the pin. (3) Use flux, that is, surface-active agent. 9 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. Another method to suppress melt-ups is to increase the heat conduction from the wire to the bobbin, by optimizing the contact of wire onto the flange of bobbin, or by changing the configuration of lead wire. (Figure 7) Note) The details of this technical brochure are subject to change without notice. It should be noted that this technical brochure does not contain specifications for goods, nor does its description guarantee the performance of goods. 10 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. Appendix A : Manufacturing tips against physical stresses 1, Sharpened edges 1.1 Bobbin In the case where TEX-E is wound on a bobbin with sharpened edges such as flanges and body part, it has a possibility that wire is damaged. With adopting a rounded bobbin and controlling winding tension as low as possible, the wire can be improved. Please refer to ‘‘3. Winding Method’’. It is easy to find a damaged point against the sharpened edge of the flange part in the following photographs through No.1 from No.3. Turned around 90 degree Photo. 1 Photo. 2 Photo.3 1.2 Sharpened tools Tools such as a tweezers or a knife are not recommendable since they can make TEX-E damaged. Some operators tend to use them for sequent winding. Photo. 4 Photo. 5 1.3 Nails In some case, nails can cause a physical damage to TEX-E. Excess stresses to the wire shown in Photo.6 are not ideal. It is better to use a rubber safe or glove, and also care the nails of operators. Photo. 6 Photo. 7 11 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. 1.4 Physical stress when bending a wire Using tools or fingers covered by soft material such as rubber are better to avoid physical stresses when bending the wire. Tweezers or a knife is not recommendable. Photo. 8 2. Excess tension Photo. 9 3. Re-winding Photo. 10 Photo. 11 Avoiding excess tension or a re-winding process is able to reduce physical damage to the wire 4. Special covers The following cover shown in Photo 12 and Photo 13 is one of tools reducing the physical damages to the wire when supplying it to transformers Photo. 12 Photo. 13 Note) The details of this technical brochure are subject to change without notice. It should be noted that this technical brochure does not contain specifications for goods, nor does its description guarantee the performance of goods. 12 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. Appendix B: Technical tips when soldering TEX-E The following is a baseline how to solder the wire to transformers. Is TEX-E adopted in your transformer equal or more than 0.4mm? No Yes Are dual or more wires wound Is your bobbin improved against at a single pin such as the insulation melting of the wire, above picture? shown as the above picture? No Yes No Yes Direct soldering is recommendable. See Advice No.1 Insulation removing or some approaches is necessary. See Advice No2. Insulation removing or some approaches is necessary. See Advice No. 2. Direct soldering is recommendable. See Advice No.1 Reference: Photo.1 and 4 Reference: Photo 8 and 10 Reference: Photo 7 and 9 Reference: Item 4.4 (P. 7) Counter reference at the same soldering condition: Photo 3 and 6 Counter reference at the same soldering condition: Photo 2 and 5 Advice 1 Advice 2 - Insulation removing (See Item 4.5) - Soldering conditions controlled at higher - Soldering conditions controlled at higher temp. and in a shorter period of time temp. and in a shorter period of time. Target: 420-450 degC and less than four Target: 420-450 degC and less than two seconds seconds - Flux - Flux - Multi-times soldering (See Item 4.2) - Multi-times soldering (See Item 4.2) - Pre-heating for transformers - Pre-heating for transformers - Improvement of winding method - Improvement of winding method (See Item 4.6 Fig.7) (See Item 4.6 Fig.7) 13 The Furukawa Electric Co., Ltd Magnet Wire Division Technical Dept. Photo.1 Photo.4 Photo.2 Photo.3 Photo.5 Photo.6 No insulation removing No insulation removing TEX-E 0.2mm TEX-E 0.7mm 450 degC for 0.8s 450 degC for 2s No insulation removing TEX-E0.2mm Dual winding 450 degC for 2s Example of Insulation removing Photo.7 Photo.8 1. Rubbing the insulation against the heater plate Photo.9 Photo.10 Insulation removing Insulation removing 2. Pulling out the transformer TEX-E 0.7mm TEX-E0.2mm Dual winding after heating the wire 450 degC for 2s 450 degC for 2s Note) The details of this technical brochure are subject to change without notice. It should be noted that this technical brochure does not contain specifications for goods, nor does its description guarantee the performance of goods. 14