Rules for selection of cooling and lubricating systems

Single Mechanical Seal

 For working temperature ≤100, fill the lubrication box with oil, water or other clean liquids directly to lubricate and cool the mechanical seal.

For temperature 100t250, add XT or LT thermoregulator to cool the seal. Or, C circulation system (Refer to HG21572-95, circulation system 4) could be used to cool the seal.

 For working temperature t250, height encreased type of thermoregulator should be added(C circulation system also could be added)

Double Mechanical Seal

Generally, all double mechanical seal should have circulation system to ensure that sealing liquid pressure is  0.050.1MPa higher than the working pressure.

 For working pressure ≤2.5MPa, A, B or E circulation system should be added. According the working temperature, different configuration should be used.

 For temperature t≤100, add A or E circulation system. GC seal port or pressure port can meet the requirments.

For temperature 100t≤160, if the seal has cooling jacket, use A or E circulation system. Otherwise, use B circulation system with GD type seal port. Or, the combination of CT thermoregulator and A circulation system also could meet the requirements.

For temperature 160t≤350, use thermoregulator first to lower the temperature and then add B circulation system (for t≤250, A system could be used). GD type seal port(or D circulation system could meet the requirements)

For working pressure 2.5MPa, add D or E circulation system for the seal. If temperature 120, CT thermoregulation should also be added.

G series seal ports are used for double mechanical seal to pressurize, store and cool the sealing liquid. The pressure of nitrogen or compressed air in the port will be 0.050.1MPa higher than the working pressure (During the start-up, the seal port also must be pressured and keep the pressure higher than the vessel, otherwise, the seal will be damaged).

Add colling coil to the GC series seal port, that becomes the GD type. Refer to figure 6.1-3. Port B and D are the cooling water outlet and inlet. The combination of GDL seal port and magnatic circulation pump will form B circulation system. The magnatic seal will reach zero leakage. Be careful to use low viscosity seal liquid, otherwise, the motor will be overload.

Shaft diameter and working temperature are very important for deciding volume of seal port. Generally, use 2L for shaft diameter ≤80; 4L for diameter 80.