Problems with gas-type mold temperature controllers
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This post was last edited by GGCTU on 2017-3-8 at 16:04. Hello, everyone. After researching the manufacturers of temperature control units available on the market, I have a few questions. First: if there is steam in the heating plate of the press, could this steam, along with the heat transfer oil, cause problems for the oil pump? Second: In the event of a sudden power outage, the temperature inside the furnace will not drop immediately; could this lead to the hot oil vaporizing at high temperatures and causing overpressure? Third: Why are the oil-gas separators designed by some manufacturers to be about 40 cm tall, while others are only 20 cm tall?
I’ve never seen this device before; come in and learn about it*
First: If there is steam in the heating plate of the press, could this steam, along with the heat transfer oil, have an adverse effect on the oil pump? Answer: Water vapor and heat transfer oil should be in separate circulation systems and must not mix with each other. Otherwise, if water enters the heat transfer oil system, it will cause the oil to emulsify and deteriorate, which may lead to failures in the heat transfer oil pump. Second: In the event of a sudden power outage, the temperature inside the furnace will not drop immediately; could this lead to the hot oil vaporizing at high temperatures and causing overpressure? Answer: It is possible, so a heat transfer oil pump should be equipped with a backup power source (or battery) to allow it to continue operating for 5–10 minutes in the event of a power outage. Third: Why are the oil-gas separators designed by some manufacturers to be about 40 cm tall, while others are only 20 cm tall? Answer: This requires designing and calculating the expandable volume of the oil-gas separator based on the amount of heat transfer oil in the entire system.
To calculate the volume, one multiplies the sum of the volumes of all pipes and equipment through which the heat transfer oil flows by the expansion coefficient of the oil. The difference between the volume of the heat transfer oil at normal temperature during shutdown and its volume at the highest operating temperature is then determined; this difference, together with an appropriate safety factor, constitutes the volume required for the expansion tank.
@jl_xu @chinazwr Guru, I have another question now. For my organic heat carrier boilers, why are the coil dimensions different for each one? The boilers in question have a capacity of 200,000 Btu; some of the coils have a diameter of 57, a wall thickness of 3.5, and an inner diameter of 50 ； Some are 51, with an inner diameter of 44 ； Another difference is the oil inlet and outlet paths; in some cases, the oil enters at one end and first flows through the inner coil before going through the outer coil ； In some cases, it enters through one end and immediately splits into two paths: one going inward and the other going outward, before finally coming out together from both ends. I’m not sure which one is more suitable for the oil circuit
The two specifications you mentioned differ by exactly one grade: the pipe diameter is smaller, resulting in a higher flow rate; this may allow it to make a few more turns inside the furnace, thereby achieving the required heat transfer area. Second, either method is acceptable; start with the inside and then move to the outside. When the oil reaches the outside, there is a temperature drop inside the tube, and the temperature of the outer coil is slightly lower. By moving both the inner and outer parts simultaneously, the inner and outer coils maintain the same temperature. Which one to choose depends on the process requirements; there is not much difference on a macro level.