Common problems of tire curing press control system

The control system of tire curing press is composed of three pin recorder, time sequence controller and pipeline. Wjs206 type pneumatic three pin recorder is used in our factory. It can continuously record the internal temperature and internal pressure of the vulcanizer, continuously record and adjust the external temperature, and clearly record the controlled parameters on the disc recording paper. Tds-0903 mechanical program controller is used in the timing controller. There are three kinds of digital program controller and programmable controller. The following describes the problems and solutions in use.

Problems and solutions of three pin recorder

When the measured pressure is transmitted to the coil spring tube or the measuring head of the temperature package to feel the temperature change of the measured medium, the free end of the coil spring tube will produce an angular displacement. The measured pressure or temperature can be recorded by driving the pointer through the four-bar mechanism.

(1) Pointer does not move

① If the pipeline is blocked or leaking, replace the components.

② If the four-bar linkage pull rod falls off, the pull rod should be put on again.

③ The pointer falls off. Put it on.

(2) The indicated value of temperature record decreases day by day. If the temperature indicating value drops day by day, the meter shall be taken down and calibrated in the laboratory to check whether the measuring range is normal. If it is abnormal, it means that the temperature bag is missing, and the temperature bag shall be replaced.

(3) If the temperature pointer moves slowly and the spiral tube is blocked or leaking, replace the element.

(4) The pointer is not sensitive in a small range. First, there is dust between the small hole at the connecting part of the pull rod and the steel ball, and the friction is large, so it is necessary to clean the small hole and the steel ball frequently. Second, the zero adjustment screw and gear are loose, so the zero adjustment mechanism shall be replaced.

(5) There are two kinds of recording nibs for recording curve, one is disposable nib, the other is hanging bottle with capillary nib. The former has a very short service life. Some of them only run out of water in two or three days. We make a small hole in the tip of the pen and then fill it with water, so that we can use it for a long time. The latter is often broken because the tip of the pen is blocked, so the tip of the pen should be cleaned; the capillary should be cleaned or replaced if there is thread plug or leakage; the suspension position of the ink bottle is too low, so it is necessary to find the position of the ink bottle.

(6) The regulator has no output, or the output pressure is small.

① If the air source pressure is less than 0.14MPa, check the air source pipeline to make it reach 0.14MPa.

② There is dirt on the end face of the nozzle, and the baffle plate cannot cover the nozzle, so the nozzle should be cleaned frequently.

③ If the throttle hole in the air circuit board is blocked or the air circuit board leaks, clean the throttle hole and replace the air circuit board.

④ The amplification of the amplifier is not enough. Adjust the adjusting screw.

⑤ If the output pipeline is blocked or leaking, clean or replace the output pipeline.

(7) Output is always maximum

① The cone surface of the orifice is not sealed and air leaks, so it does not play the role of throttling, so the air circuit board should be replaced.

② The valve seat of amplifier is not tight with the steel ball. Adjust or replace the amplifier.

③ The input and output pipelines shall be connected reversely to make them connected correctly.

(8) Unstable external temperature control

① If the negative feedback nozzle is blocked or the pipeline leaks air, clean the nozzle or replace the pipeline frequently.

② If the position of the proportion bar is not adjusted properly, the proportion bar shall be adjusted repeatedly until the external temperature curve is stable.

2 problems and solutions of program controller

According to the predetermined vulcanization process requirements, the cycle sequence, entry and discharge time of the medium entering the capsule during tire vulcanization are controlled by the pneumatic signal sent by the program controller through the pneumatic shut-off valve. In the past few years, there has been abnormal phenomenon of program control in the process of over vulcanization, among which the frequency of domestic mechanical program controller is more than that of digital and programmable controller. The following mainly introduces the problems and solutions of tds-0903 mechanical program controller.

(1) jump procedure

Under normal circumstances, when the dial on the timing plate contacts with the horizontal piece of the program switch memory device and pushes it to dislocate, the normally open contact of the program switch is connected, so the program motor drives the program drum to rotate, so that the dial on each setting plate accurately acts on the memory device of the output circuit, making the air valve or the external control switch turn on or off as required. At the same time, due to the rotation of the program drum, the block of the limit disk is driven to act on the lever of the memory device of the program switch, and the action of the lever makes the normally open contact of the program switch open, so the program motor stops rotating, and the cross piece returns to the original position, which completes a step of program action. There are two reasons for this phenomenon.

① The normally open contact of the program switch can not be opened, which makes the program motor run continuously. The program switch should be replaced.

② The position of lever and crosspiece shall be adjusted if the crosspiece fails to return to its original position and the program switch is combined by pressing sound.

(2) Program drum or timing dial does not rotate

① If the program motor or timing motor is damaged, replace the motor.

② If the mechanical gear is loose, tighten the fixing screws and check the gear gnawing.

(3) Insufficient output air pressure

① If the total air supply pressure is less than 0.35Mpa, check the total air supply pipeline to make it reach 0.35Mpa.

② The air valve ball in the program controller is stuck by dirt. Clean the air valve ball.

③ The output pipeline or pneumatic shut-off valve leaks, and the air leakage is solved.

(4) Program does not execute after mold closing

① If the power switch of the program controller is not turned on or the contact is not good, turn on or replace the power switch.

② Program motor is broken, replace the motor.

③ If the mode closing limit master switch is not pressed and there is no mode closing signal, adjust the mode closing limit switch position.

(5) At the end of vulcanization, the mold can not be opened,