204 Mechanical seal What are the manufacturer's maintenance methods and mechanical seal precautions?

Because the application environment of mechanical seal is very messy, and the seal structure is more complicated, the sealing degree of mechanical seal is very simple to be damaged, so it is very important to repair the mechanical seal.

1、 Precautions for disassembly of mechanical seal

1. The installation order of mechanical seal is opposite to that of the mechanical seal used to disassemble the pump.

2. Be careful in the process of dismantling the mechanical seal. Do not use a hammer, flat shovel, knock the mechanical seal, or damage the sealing surface of the dynamic and static rings of the mechanical seal.

3. If it cannot be disassembled due to too much dirt such as oil stain, clean it with kerosene Mechanical seal for kettle Clean it and then disassemble it. Keep all parts of the mechanical seal intact.

2、 Requirements and process of mechanical seal maintenance

1. After removing the mechanical seal, first check the pump body with the organic seal of the device to meet the following requirements:

(1) Maximum shaft bending ≤ 0.05mm, axial displacement ≤ 0.05mm;

(2) Runout at dynamic ring seal ring ≤ 0.01mm;

(3) The surface roughness of the shaft or shaft sleeve at the mechanical seal part of the device is 1.6 μ m. The surface roughness touching the sealing surface of stationary ring is 3.2 μ m；

Secondly, repair the mechanical seal:

(1) Check the components of mechanical seal. All components must be complete and undamaged, and the dynamic and static ring sealing surfaces must be free of scratches, bruises and other defects. If any damage is found, correct or replace the mechanical seal from scratch;

(2) Check whether the tension of the tension spring becomes smaller. If it becomes smaller, replace the tension spring from the beginning;

(3) Check whether the inner wall of the seal body and the inner and outer surfaces of the seal end cover are damaged, and repair them in time if any problems are found.

3、 Preparation before installation of mechanical seal and precautions

After the above maintenance operations are completed, it is necessary to start the mechanical seal from the beginning and make preparations before the installation:

1. If a new mechanical seal is replaced, check whether the type and standard of the mechanical seal are correct and whether the quality meets the standard;

2. The anti rotation groove end at the tail of the stationary ring and the top of the anti rotation pin should adhere to an axial clearance of 1mm~2mm to avoid buffer failure;

3. The end faces of the moving and stationary rings shall be cleaned with alcohol, and other metal parts shall be cleaned with gasoline and dried with clean compressed air. Carefully check to ensure that the sealing faces of the moving and stationary rings are free from any damage. Before installation, two "0" shaped rubber sealing rings shall be coated with a layer of smooth ointment, and the end faces of moving and stationary rings shall not be oiled.

4、 Installation sequence and precautions of mechanical seal

1. After the relative orientation of the rotor and the pump body is fixed, determine the device orientation of the mechanical seal, and calculate the positioning dimension of the seal on the shaft or shaft sleeve according to the device dimension of the seal and the orientation of the stationary ring in the gland;

2. Install the seal moving ring of the machine. After the moving ring is installed, ensure that it can move sensitively on the shaft;

3. Assemble the assembled stationary ring part and movable ring part;

4. Install the seal end cover in the seal body and tighten the screws.