Comparison of three common types of electrically heated radiant tubes

Today, we will talk about the common three kinds of electric heating radiation tube shell. If there is something wrong, please correct it. 

Electric heating radiant tube consists of two parts of shell and heating core. Shell we usually choose three kinds such as seamless steel tube, steel coil and centrifugal cast tube.

Seamless steel tube and steel plate thickness of pipe is usually 3 mm, but it is the plus or minus tolerance of domestic steel pipe with steel plate that customer purchased 3 mm thickness is 2.8 mm or so mostly. It is not cut corners but raw material bought such a situation, there are two kinds of our manufacturer to purchase raw materials prices; one is calculate by theoretical weight, the price of the other one is the price of the actual weight. In 2018, I encountered such a problem caused by seamless steel tube being made into outer tube produced by another maker. At that time, the outer tube was seamless steel tube, and the radiation tube had been broken down for more than eight months. According to the site situation, the fundamental cause of the breakdown was short circuit caused by too much oxide.

Steel plate coil tube do radiation tube outer tube raw materials are usually the choice of domestic stainless steel plate or Swedish plate, general processing technology plate open to the size of the plate rolling machine directly rolled good welding is done, pay attention to a little will be welded with the lathe to adjust the ovality. After the bottom of the pipe and the flange are assembled, the welding seam will be detected as a whole, usually by pressing or penetration, in order to ensure that the radiation pipe in the use of air which will not lead to oxidation skin and carbon ash accumulation too fast to cause breakdown.

Centrifugal casting pipe in comparison of seamless steel tube with plate bending pipe has the advantage of high strength of resistance to deformation, the same size of centrifugal casting pipe compared with seamless steel tube surface area about 25%, the same power voltage can improve the heat energy utilization, the disadvantage is the thickness of the general control compared between 4.5 mm to 5.5 mm choice in terms of volumes of seamless steel tube and although a longer service life of the weight on purchasing cost is high. When selecting the pipe body, the whole pipe will be pressed to detect and select the required length part. The inner wall of the outer pipe will leave a 1.5mm machining thickness on one side for the boring and de-oxidizing part. There is no big difference between the tube bottom with selected steel plate cutting and precision casting.
When we maintain the equipment every year, we should also take care of the radiant tube. The simple and quick way is to grind the steel wire disc in the tube and blow the tube mouth in the direction of the downward pressure air.