Preparations for the production of electric tubular heating Elements

- Aug 23, 2020-

Preparations for the production of electric tubular heating Elements:

The process of electric tubular heating elements is not very complicated, and the process is not too many, but each process directly affects the electrical performance and service life of the heating tube.

First of all, let's talk about the preparations for the production of electric heating tubes

The pipe blanking can generally be carried out on a lathe or a pipe cutting machine. After blanking, the burrs at both ends are removed. The method of deburring can be carried out mechanically by clamping the conical milling cutter on the power head.

The pipe cleaning adopts the methods of alkali degreasing and acid derusting, and the pickling solution uses 10% hydrochloric acid or 15% sulfuric acid. In order to eliminate and reduce the degree of corrosion, a small amount of corrosion inhibitor is generally added to the acid solution. The corrosion inhibitor not only reduces metal corrosion, but also reduces hydrogen embrittlement due to the formation of hydrogen. Notting or animal glue are often used as corrosion inhibitors. The time and temperature of pickling have a great influence on the quality of pickling. In 10% sulfuric acid (2% Notting and 5% animal glue are used as corrosion inhibitor), if the temperature is 20 degrees, the pickling time is 20 minutes, if the temperature is increased to 60%, the pickling time should be reduced to 5-10 minutes. Rinse with clean water after pickling, neutralize in 5% sodium carbonate solution for three minutes, rinse with hot water and dry.

After cleaning the tube, brush the inner wall of the tube, that is, first use a steel wire brush with the same outer diameter as the inner diameter of the tube to brush back and forth on the tube brushing machine several times. The tube and the steel brush rotate in opposite directions, and the tube moves back and forth along the axis. . Wiping the tube after brushing. The pipe wiper is performed on a special pipe wiper. The pipe wiper is a long rod with white gauze wrapped around the end. After the machine is started, the long rod is driven by the motor to rotate. The pipe goes back and forth, so that the gauze wipes on the inner wall of the pipe. Go to the dust. After cleaning the brush tube and wiping the tube, the inner surface of the tube shows a metallic luster. At this time, the two ends of the tube can be plugged tightly with rubber plugs to prevent a new oxide layer in the air.

The disadvantage of the above-mentioned method of cleaning pipes with a rotating brush is that the brushes, gauze, etc. are quickly contaminated, which seriously affects the cleaning quality. In order to avoid this shortcoming, a KOS-type pipe cleaner has been designed internationally.

The KOS type pipe cleaner uses a pneumatic tool to inject a polyethylene sponge-like round plug made of tape, which is blown through the pipe to be cleaned. When working, put the pipe to be cleaned into a pneumatic tool by hand. The tool is connected with compressed air with a maximum pressure of 6 atmospheres. The pedal is used to trigger the gun to shoot the plug while forming air pressure behind the plug. , This pressure blows the plug through the entire pipe, so that any sticking dirt left in the pipe is removed. When reversing, the pneumatic punch automatically sends the new plastic stopper to the shooting position.

The maximum outer diameter of the cleaning pipe of this equipment is 13mm, it can clean 25-40 pipes per minute, and the air consumption is 0.2 liters per shot.