Speed control system, injection

Proper machine cycle settings are also important for energy savings. The injection speed control system (available on new machines as an option or as a retrofit on old machines) optimizes the speeds available for specific time intervals. The injection high volume pump is available for a fixed time period and is then dropped out of the system. This time period should coincide with... 

Since these MPUs are used to control fuel-injection systems, it might be interesting to know the 24,000-km rehabiUty (the warranty period). Assuming an average speed of 80 km/h, 300 h of use are obtained. The rehabiUty would be estimated as... 

BWRs do not operate with dissolved boron like a PWR but use pure, demineralized water with a continuous water quality control system. The reactivity is controlled by the large number of control rods (>100) containing burnable neutron poisons, and by varying the flow rate through the reactor for normal, fine control. Two recirculation loops using variable speed recirculation pumps inject water into the jet pumps inside of the reactor vessel to increase the flow rate by several times over that in the recirculation loops. The steam bubble formation reduces the moderator density and... 

The initial development of either volume-based or injection metering dose-control systems aimed at achieving a uniform controlled dose across a treatment area that was independent of machine variables, particularly forward speed. However, there is substantial evidence to show that the target requirements for many plant-protection products are not uniform across a field, and that there is the... 

These samples are produced at PPITB Training Centre on an older machine than that used for the bracket. It is a Windsor 130 tonne machine with manually operated, relay-activated control. There are only two injection speeds available. The more sophisticated machine requires a lot more understanding of the process to realize its potential, but its automated control system then delivers highly reproducible and accurate results. The older machine is at the mercy of disturbance factors which it is unable to accommodate, especially variability in operator performance. 

The control system is there to ensure repeatability during moulding operation. It monitors both the hydraulic system and the process parameters such as temperature, injection speed, screw retraction speed and injection and back pressure. The ability to control the process has a direct impact on final part quality, part to part consistency and economy. The nature of the control system may vary from a simple relay switch to a complex microprocessor system with closed-loop control. Some of the components of the machine control system will now be introduced. 

The injection molding machine used is Arburg S220 type. It has a hydraulic servo-valve-control system and high speed injection function for thin wall molding. 

Traditional injection molding method was tried to mold the nozzle plates but lail. Typical condition used was injection speed of 100 mm/s and mold tenperature of 80°C. Figure 6 shows a short shot caused by grating effect. After applying the vario-thermal control system and high injection speed fimction, good results were obtained finally. 

This standard could be adapted to the fuel compressor for the natural gas to be brought up to the injection pressure required for the gas turbine. Covers the minimum requirements for reciprocating compressors and their drivers used in petroleum, chemical, and gas industry services for handling process air or gas with either lubricated or nonlubricated cylinders. Compressors covered by this standard are of moderate-to-low speed and in critical services. The nonlubricated cylinder types of compressors are used for injecting fuel in gas turbines at the high pressure needed. Also covered are related lubricating systems, controls, instrumentation, intercoolers, after-coolers, pulsation suppression devices, and other auxiliary equipment. 

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