英文翻译(精密注射成型技术进展)

英文原文：P recision injection molding technology of progressusing precision injection molding machine to replace conventional injection molding machinePrecision injection molding machine generally larger injection power, in addition to such injection pressure and injection to meet the requirements in terms of speed, power itself will be on the injection products improve the accuracy of a certain role. Precision injection molding machine control systems generally have high control precision, it is requested by the products themselves. High accuracy can be guaranteed control of injection process parameters has good accuracy, precision products in order to avoid fluctuations due process parameters change. Therefore precision injection molding machine generally of the injection, injection pressure, injection rate and pressure-pressure, back-pressure and screw speed process parameters such as a multi-level feedback control. Precision Injection requirements of its modulus system has sufficient rigidity, accuracy or products will be a model for the elastic deformation decreased. Second-Die-Die of the system must be able to accurately control the size, or too large or too small a model of precision products will have an adverse impact. So in the design, it should be considered Die rigidity, stiffness, as well as a model system in order to accurately control the size of the precision products, especially flat-panel thin-wall products. When Die larger, must-oriented column deflection check. Precision injection molding machine also must be able to work in the hydraulic circuit precise temperature control, work to prevent the oil due to temperature changes caused viscosity and flow changes, further injection process parameters leading to fluctuations而使products would lose their accuracy.1. parts molding cycle time consistencyGeneral typical injection molding machine with three modes: manual, semi-automatic and fully automatic. As the influence of various factors, each of the previous two models molding cycle time may be different, it would affect the temperature and materials to die in the Liaodong stay, thereby affecting the accuracy of parts, in precision Molding should try to use the automatic mode.2. precision injection molding machine screw temperature control and the design of newInjection Molding Machine cylinder automatic thermostat on the cycle of opening and customs led to the Liaodong, melting material density and viscosity changes, thereby affecting the quality and dimensional accuracy of parts of the cyclical fluctuations in the injection molding machine nozzle close to Die Therefore, the temperature of the nozzle molded parts also have a significant impact on. Modern injection molding machine equipped with a special process control software to control temperature fluctuation, which is proportional integral differential (P ID) control. At least from the barrel temperature difference galvanic point perspective, the P ID parameter optimization can completely eliminate temperature fluctuations.To the quality and stability of the plastic parts, plastics injection molding machine unit is very important. To the plastics unit is an important standard to judge: injection volume, plastics rate, injection rate, the polymers in the plastics unit at the time.As the quality of plastic parts for the dimensional accuracy error of a very important impact, and it should be precise injection control of the injection molding machine. Improve measurement precision injection molding machine of the most effective ways is to use technology to achieve the smallest screw diameter, especially for the light parts especially. The measurement of the relative screw length and the overall length of screw smaller, in the plastics materials unit at the time also become shorter. Screw thread is similar to widening the materials can be avoided stay longer so that the screw and stable operation. Lo deep groove width than correspondingly smaller, which create a lot of engineering plastics parts of the small diameter screw particularly effective. Melt homogeneity and are not small compression ratio decreases, it is because from the very shallow groove Lo caused very strong result of the shear rate. Feeding the difficulty of the design, it must ensure that all aggregates can be fed into evenly. Considering the need to shorter cycles, plastics rate must also be big enough, in the design of the feed must be effectively resolved the contradiction between. In addition, if adopted by a two-stage injection screw to achieve precise control injection error, which requires the measurement of the melt through spherical valve detected by injection to injection molding machine in the Detroit injection molding machine.Before microprocessor controlled by the injection molding process can not be obtained through injection precision voltage comparator has been successfully resolved. V oltagecomparator allows Transmitter and other sensitive came with the very precise voltage signal passed, and when the set point appears to be following the true value of a timely signal immediately transmitted to the microprocessor control of the order, by order of the cycle of operational procedures Asynchronous from time to time through a direct transfer of the signal process to eliminate, greatly improving the control accuracy.precision molding technology1. In the mold injection-compression molding applications (ICM) technologyICM technology is the means to open a certain distance die under the conditions of the beginning injection, injection to a certain amount, the mold cavity beginning of the closure of the melt compression, injection mold completely closed at the termination, and then packing, cooling until the removal products. Through injection-compression molding of compression products to compaction, making products on the surface of uniform pressure distribution, the compaction products such size high accuracy and stability, small deformation. It is in the mould open circumstances melt into the cavity and, therefore, mobile channel, for the low pressure injection molding, and reduce or eliminate the pressure caused by the resin-molecular orientation of the stress and products, which improve products, dimensional stability. ICM technology and flexible control capability than the injection mould has greatly improved. Therefore use of this technology can produce more precision parts, especially the high-precision cylindrical-shaped parts.2. High-speed injection moldingHigh-speed injection molding method of filling melts faster rate than the traditional 10 to 100 times, melt in the mold cavity to produce high shear flow, decrease viscosity, injection speed, slow down plastic surface hardening, thus improving thin Forming products wall thickness limit, inhibit excessive molding pressure, as well as because of the low-voltage mobile mode, the products reduce stress. The thin-wall precision products, we can use the injection screw at the forward from the melt energy absorption in the screw after the cessation of movement through the expansion of high-speed melt full cavity to achieve.3. No-pressure injection moldingNo-pressure injection molding technology refers to the plastic melt high-speed, high-pressure filling into the mold, and then close in the nozzle needle to melt the plastic mold cavity products automatically compensate for different parts of the contract, such products can be greatly reduced warpage. However, this method requires prior estimate packing contraction added, hence the need for the injection of a higher cavity pressure value, and we need clamping force also high.4. Other Intelligent Control TechnologyPrecision injection molding processing conditions in the process of continuous monitoring and implementation of precise control is very important. With the development of computer technology, computerized injection molding has been widely used. Among them, statistical process control (SPC), P ID technology, fuzzy logic control (FCC), network control center (NNC) method and the processing model based on the reverse of the backbone network size control.Advantages1.High production rates. For example, a CD disk can be produced with a 10-12scycle in high melt flow index PC.2.Relatively low labor conent. One operator can frequently take care of two or moremachines, particularly if the moldings are unloaded automatically onto conveyors.3.Parts require little or no finishing. For example, flash can be minimized and moldscam be arramged to automatically separate runners and gates from the part itself.4.Very complex shapes can be formed. Advances in mold tooling are largelyresponsible.5.Flexibility of design ( finishes, colors, inserts, materials ). More than one materialcan be molded through co-injection. Foam core materials with solid skins areefficiently produced. Thermosetting plastics and fiber-reinforced shapes areinjection molded.6.Minimum scrap loss. Runners, gates, and scrap can usually be reground. Recycledthermoplastics can be injection molded.7.Close tolerances are obtainable. Modem microprocessor controls, fitted toprecision molds, and elaborate hydraufics, facilitate tolerances in the 0. 1% rangeon dimensions and weights ( but not without a high level of operational skills inconstant attendance).8.Makes best use of the unique attributes of polymers, such as flow ability, lightweight, transparency, and corrosion resistance. This is evident from the numberand variety of molded plastic products in everyday use.Disadvantages and Problems1.High investment in equipment and tools requires high production volumes.ck of expertise and good preventive maintenance can cause high startup andrunning costs.3.Quality is sometimes difficult to determine immediately. For example, plst-moldwarpage may render parts unusable because of dimensional changes that are not completed for weeks or months after molding.4.Attention is required on many details requiring a wide variety of skills andcross-disciplinary konwledge.5.Part design sometimes is not well suited to efficien molding.6.Lead time for mold desin, mold manufacture and debugging trials is sometimes verylong.ConclusionOn the high-precision plastic products, and high-performance requirements of the growing precision injection molding technology is the impetus for moving forward, people on the principle of precision injection molding, the constant deepening of understanding of precision injection molding technology is the basis for progress. With new materials, new processes and new equipment has emerged, particularly in the plastics processing computer is the wide application of the precision injection technology to create goodconditions. As long as a reasonable use of these technologies, we will be able to produce sophisticated products.中文对照：精密注射成型技术进展采用精密注塑成型机，以取代传统的注塑机精密注塑机注射功率一般较大，除了注射压力和注射速度满足要求外，电源本身将是提高注塑产品精度的以个重要角色。