How to control the ordinary cylinder to stop at any position, and the three-position five-way middle position will jump? Is there any other way?

The cylinder is a cylindrical metal part, which guides the piston to do linear reciprocating motion in the cylinder. Air expands in the engine cylinder, converting heat energy into mechanical energy; The gas is compressed by the piston in the compressor cylinder to increase the pressure.

The casing of a turbine, rotary piston engine, etc. Also commonly referred to as "cylinder". Application fields of cylinder: printing (tension control), semiconductor (spot welding machine, chip grinding), automation control, robot, etc.

Extended data:

Basic concepts:

A cavity in the cylinder block of an internal combustion engine where a piston is placed. It is the trajectory of the piston movement, in which the gas burns and expands, and it can also radiate a part of explosive residual heat transmitted by the gas through the cylinder wall to keep the engine at normal working temperature.

There are two types of cylinders: one-piece and one-piece casting. Single casting is divided into dry casting and wet casting. When the cylinder and the cylinder block are cast into a whole, it is called an integral cylinder; When the cylinder and cylinder block are separately cast, the single cast cylinder barrel is called cylinder liner.

The direct contact between cylinder liner and cooling water is called wet cylinder liner; Cylinder liners that are not in direct contact with cooling water are called dry cylinder liners. In order to keep the close contact between the cylinder and the piston and reduce the friction loss of the piston moving in it, the inner wall of the cylinder should have high machining accuracy and accurate shape and size.

Common faults:

1, the cylinder is cast, and the cylinder should be aged after leaving the factory to completely eliminate the internal stress generated in the cylinder casting process. If the aging time is short, the processed cylinder will be deformed in the future operation.

2. The stress on the cylinder during operation is very complicated. In addition to bearing static loads such as the pressure difference between the gas inside and outside the cylinder and the weight of various components installed in it, it also bears the reaction force to the static part when steam flows out of the stator and the force to the cylinder under the cold and hot conditions of various connecting pipes. Under the interaction of these forces, the cylinder is prone to plastic deformation and leakage.

3. The cylinder load increases or decreases too fast, especially when the engine starts, stops and the working conditions change rapidly, the temperature of the cylinder changes greatly, the heating mode of the cylinder is incorrect, and the insulation layer is opened too early when the engine stops and overhauls, resulting in large thermal stress and deformation of the cylinder and flange.

4. The cylinder produces stress during machining or after repair welding, but the cylinder is not tempered to eliminate it, resulting in large residual stress in the cylinder and permanent deformation in operation.

5. In the process of installation or maintenance, due to the maintenance process and technology, the expansion gap of the inner cylinder, cylinder diaphragm, diaphragm sleeve and steam sleeve is not suitable, or the expansion gap of the lug pressure plate is not suitable, and the cylinder is deformed due to huge expansion force after operation.

6. The cylinder sealant used is of poor quality, with too many impurities or the wrong model; If there are hard impurity particles in the cylinder sealant, it will make it difficult to closely combine the sealing surfaces.

7. Insufficient tightness of cylinder bolts or unqualified bolt materials. The tightness of cylinder joint surface is mainly realized by the tightness of bolts. Thermal stress and high temperature generated when the unit starts or stops or increases or decreases the load will cause stress relaxation of bolts. If the stress is insufficient, the pre-tightening force of the bolt will gradually decrease.

If the bolt material of the cylinder is not good, under the action of thermal stress and cylinder expansion force for a long time, the bolt will be stretched, plastically deformed or broken, resulting in insufficient sealing and cylinder leakage.

8. The tightening sequence of cylinder bolts is incorrect. Generally, cylinder bolts are tightened from the middle to both sides at the same time, that is, from the place with the largest vertical radian or the place with the largest stress and deformation, which will transfer the gap at the place with the largest deformation to the free ends before and after the cylinder, and finally the gap will gradually disappear.

If it is tightened from both sides to the middle, the gap will be concentrated in the middle, and the joint surface of the cylinder will form an arch gap, resulting in steam leakage.

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