1. Scope The length of the metal sleeve from the measuring end is not less than 500mm.
Multiple armored lengths of 1m were combined into different lengths and tested at different calibration temperature points. Among them, the change of the calibration point at 800Â°C is more obvious, the variation with the length shorter than 500mm reaches -0.56Â°C, the maximum variation with the length of 500mm is -0.29Â°C, and the variation with the length greater than 500mm is smaller. Therefore, in JJF1262-2010, it is specified that the length of the metal sleeve to be sheathed is not less than 500 mm.
2. Metering characteristics The metering characteristics of armored thermocouples include room temperature insulation resistance and indication tolerance tolerance specifications.
(1) Insulation resistance at room temperature By measuring the insulation resistance at room temperature between the thermocouples and between the thermode and the metal case, the quality of the mating device can be judged. Therefore, JJF1262-2010 specifies the insulation resistance measurement item at room temperature.
(2) Tolerance of indication value It is judged whether the value of the inspection indication is within the tolerance limit, and the indication tolerances of level 1 and 2 are specified. Since the output signal of the armored thermocouple is terminated to the compensation wire, the compensation wire correction value is added to the deviation calculation formula of the indication value and the index table.
(3) Why does the new system do not anneal before calibration?
In the related standards of the mating couples, it is stipulated that after the new mating couples are annealed, the indicating values â€‹â€‹are calibrated. In response to this problem, the drafting team selected different types of armored couples to perform a large number of tests before and after annealing (primary and secondary annealing) at different calibration temperature points, whether the first annealing or the second annealing. Compared with the value shown before annealing, the maximum difference is about one-tenth of the tolerance. The test results show that if the even-wire material is fully annealed before leaving the factory, whether or not the new anneal annealing is performed will have little effect on the calibration results. Therefore, JJF1262-2010 omitted the work of anneal before the calibration of the new system.
3. Calibration conditions (1) Environmental conditions Armored thermocouples require that the environment of the electrical test equipment comply with the requirements of their corresponding regulations; the environment of the thermostat equipment should be free of airflow disturbances.
In order to meet the requirements of the measuring zone on the measuring temperature zone (satisfying the length of the diameter of the 5 times thermocouple as the â€œminimum immersion depthâ€ of the thermocouple), the drafting team designed a length of 80 mm, a hole depth of 65 mm, and an aperture ratio to be calibrated. The uniform metal temperature block with a large diameter (0.5-1.0) mm is used in the assembly, and the index of the tube-type furnace uniform temperature block obtained through a large number of tests is shown in Table 1 of JJF1262-2010. When calibrating, place the geometric center of the temperature block at the geometric center of the tube furnace.
4. Calibration method (1) Calibration of indication Although the measurement range of the mating device is wide, it is limited by the use range of the standard device and the constant temperature device, so the calibration zone is calibrated. The calibration of the armored and even indication values â€‹â€‹uses a comparison method. According to the size of the diameter, at least 3 calibration temperature points are selected. When calibrating, the compensating wire must be connected to the signal output end (or the signal output terminal lead) of the armored thermocouple, and then the reference end should be placed in the freezing point thermostat.
(2) Depth of insertion of the temperature mounting box below 300Â°C When calibrating the mounting adapter below the temperature range of 300Â°C, the insertion temperature of the temperature sensing point of the standard unit and the measuring terminal to be calibrated shall not be less than 200mm. In the relevant standards, it is specified that the standard device and the inserted device have a depth of 300 mm. The drafting team used the first-class platinum resistance thermometer as an etalon, and tested the insertion depths of 200 mm and 300 mm in thermostatic oil tanks and dry well furnaces for different lengths of helium fittings. The maximum difference between the results was only -0.14. Â°C. The insertion depth of the measuring end should not be less than 200mm.
(3) The impact of the immersion depth of the standard mercury thermometer (original second grade) on the calibration result The standard mercury thermometer (formerly second class) was used as the standardizer. When calibrating an assembly, immersing in the upper or lower limit of the standard thermometer has little effect on the calibration result.
The drafting team immersed the standard mercury thermometer with a calibration temperature point of 200Â°C and a measuring range of 150Â°C to 200Â°C to the upper limit. The calibration results were compared with the calibration results using a standard platinum resistance thermometer as the standard. The maximum difference was 0.03Â°C.
The standard mercury thermometer with a range of 200Â°C to 250Â°C is immersed to the lower limit. The calibration result is compared with the calibration result using a standard platinum resistance thermometer as the standard. The maximum difference is 0.05Â°C.
(4) Depth of insertion of thermocouples in the temperature zone above 300Â°C. Standard thermocouples are fitted with high-aluminum protection tubes and are fitted into the holes of the temperature-equalization block in the tube furnace respectively. The measurement ends are in contact with the bottom of each hole. This thermocouple insertion depth is about 325mm.
1. PVC special screw with high performance hard chromium plating or with stainless dteel
2. Widen the safely door( Optional)
3. Equipped with two or more core pulling device
4. Multi stage of air cool device on barrel for precise control of material temperature
5. Large torque plasticizing hydraulic motor
AOTAI Servo Driving System
1. Show High Precision:The accurate injection positioning,pressure, speed ang pressure maintaining, to ensure the ensure the repeatability error of injection accuracy less than 0.3%to achieve precision molding.
2. Super Energy-Saving Features:Compared with standard injection machine, the energy saving rate can reach 40%-70% for the same plastic production.
3. High Efficiency:Compated with standard machine,the total efficiency can increase by 10% and dragging capacity is can increase by 18%
4. High Respomse System:The system acceleration and deceleration performance is quite agile and force &speed regulation is very sensitive. The sampling processing speed can reach 100KHZ and system quick start time can reach 0.05s.
5. Maintain Stability and Reliability:The pressure or speed is stable and switch of pressure maintaining is smooth and accurate.
6. Low Oil Temperature:Avoid high pressure unloading and low oil temperature situation during operation. Improve the operation performance,promote using efficiency and save a large quantity of coolong water.
J system characteristic
Design and reseatch on high energy-saving Injection Molding Machine has been regarder as our National Torch Plan and we are the earliest company who is engaged in this project. Servo motor can disctate different machine action according to product workmanship requirement. To inqut data into the controller and instruct different workload demand of every machine action quickly. The linearity of servo driving system operational process keeps good tracking with workmanship instrucion. In this case, the system pressure and flow becomes a closed loop, which achieves high machine performance & high energy-saving by 40%-70%. With this high-response system, the efficency of machine can be more than 98%.
High combination device
1. Imported brand controller
Imported options: mainly KEBA and B&R,Display the concept of high response & multfunction people-oriented control
2. CE standard system & series
hybrid system & machine series, which is honored with CE certificate, to improve the safety rate during machine operation
3. Overlap movement high speed system
Ejection or plasticizing when mold opening & clamping, to increase machine cycle and achieve high efficiency
4. High efficiency non-standard power/capacity expansion systm
Add driving function on standard machine power, so to increase operation cycle obviously & achieve super quality and high efficiency.
5. High speed acceleration/accumulator unit
Suitable for the production of thin-wall& fast molding products, so to meet the processing requirements of precision & high difficulty products
6. High precision injection unit pressure sensor device
Improve system pressure real time cycle during injection unit operation, so to realize the closed-loop effect of injection/holding pressure and pre-plasticizing & back pressure
7. High precision injection servo valve/closed-loop device
Applicable to processing requirements of extremely precision high end products, so to increase injection repeat accuracy efficiently
8. Single cylinder fast injection device
Appropriate for 360T(or below) machine is clamping unit to match single cylinder high injection molding, so to ensure the production of ultrathin-wall products ,and realize super quality and high efficiency.
9. Optimum function combination of clamping & injection
Suitable for the pertinent special products by nonstandard and optimum customized combination of clamping unit & injection unit machine, so to reach most suitable application of optimum mass production.
Pvc Pipe Making Machine,Pet Injection Molding Machine,Automatic Pet Preform Injection Machine,Pvc Injection Molding Machinery
NINGBO BEILUN ALLWAY MACHINERY CO., LTD. , https://www.aotai-machinery.com