Industrial chiller low temperature chiller screw chiller operating parameter reference-refrigeration

In the process cooling water system, our common chillers are divided into industrial chillers, low-temperature chillers, and screw chillers. Then what are the differences and advantages and disadvantages of these three chillers, given the incomplete understanding of customers in the market, , HYZOE Refrigeration will share with you the advantages and disadvantages of the above three chillers

When the HYZOE refrigeration compressor is running, its oil pressure should be 0.1-0.3MPa higher than the suction pressure.

◆ If there is a sight oil hole on the crankcase, the oil level must not be lower than 1/2 of the sight oil hole; if there are two sight oil holes, the oil level should not exceed 1/2 of the upper sight oil hole, no less than Look down at 1/2 of the oil hole.

◆ The temperature of the crankcase is generally maintained at 40-60 ° C, and the maximum cannot exceed 70 ° C.

◆ The temperature of the compressor shaft seal must not exceed 70 ℃.

◆ The discharge temperature of the compressor does not exceed 135 ° C.

◆ The suction temperature of the compressor is 5-15 ℃ higher than the evaporation temperature.

◆ The operation sound of the compressor is clear and uniform, and it has rhythm and no impact sound.

◆ The compressor motor runs stably and the machine temperature is normal.

◆ Oil separator equipped with automatic oil return device can return oil automatically.

◆ The voltage and current are consistent with the voltage and current of the unit nameplate. Too high or too low will affect the safe operation of the chiller

Chiller advantages:

◆ Simple materials, common metal materials can be used, easy processing and low cost.

◆ Simple system installation and easy lubrication.

◆ Multi-head, high-speed multi-cylinder can improve performance.

Disadvantages:

◆ Many parts, many wearing parts, complex maintenance, frequent, high maintenance costs.

◆ Low compression ratio and small cooling capacity.

◆ The single head has poor adjustment performance under partial load. The cylinder can be adjusted without stepless adjustment.

◆ Reciprocating up and down, with large vibration.

◆ The weight index of unit cooling capacity is large.

Symbol of normal operation of HYZOE refrigeration screw chiller

◆ Compressor discharge pressure is 1.1-1.5MPa

◆ Compressor exhaust temperature is 45 ~ 90 ℃; maximum temperature must not exceed 105 ℃.

◆ The oil temperature of the compressor is 40 ~ 55 ℃.

◆ The oil pressure of the compressor is 0.2-0.3MPa

◆ The running current of the compressor is within the rated value to avoid burnout of the motor.

◆ The compressor runs smoothly and evenly. There should be no knocking or abnormal sound.

◆ The condensing temperature of the compressor is generally controlled at about 40 ℃, and the inlet and outlet temperatures of the cooling water are generally 32 ℃ and 37 ℃

◆ The evaporation temperature of the compressor unit should be 3 ~ 5 ° C lower than the outlet temperature of the chilled water. The inlet and outlet temperatures of chilled water are generally 7 ° C and 12 ° C.

◆ The oil level of the compressor oil must not be lower than 1/3 of the oil sight glass.

◆ During normal operation of the unit, there should be no oil stains on any part, otherwise it means a leak and must be immediately detected and repaired.

◆ The voltage and current are consistent with the voltage and current of the unit nameplate. Too high or too low will affect the safe operation of the chiller.

advantage:

◆ Simple structure, few moving parts, few wearing parts, low failure and long life.

◆ Smooth circular motion, no "surge" phenomenon during low load operation, low noise and small vibration.

◆ Easy to adjust, can be adjusted steplessly within the range of 10% to 100%, high efficiency under partial load

◆ Small size and light weight, it can be used as a fully enclosed large capacity unit.

◆ Not sensitive to wet stroke

◆ It is operated under positive pressure, and there is no problem of external air intrusion and corrosion.

Disadvantages:

◆ Price is higher than piston type.

◆ The capacity of single machine is smaller than that of centrifugal type, and the speed is lower than that of centrifugal type.

◆ The lubricating oil system is more complicated and consumes more fuel.

◆ High machining accuracy and assembly accuracy are required.

Sign of normal operation of centrifugal chiller

◆ The reading of the ammeter on the operation panel does not exceed the specified value.

◆ The compressor inlet temperature should be 1-2 ℃ higher than the evaporation temperature, and the highest should not exceed 15 ℃.

◆ Compressor exhaust temperature does not exceed 60-70 ℃, otherwise it will cause deterioration of cooling water and damage to cooling water system.

◆ The condensing temperature is 2-3 ° C higher than the cooling water outlet temperature, the cooling water inlet temperature is not higher than 32 ° C, and the refrigerant has a subcooling degree of about 2 ° C.

◆ The evaporation temperature is 2-3 ° C lower than the temperature of the chilled water outlet. When the user's requirements are met, the temperature of the chilled water outlet temperature should be high.

◆ The oil pressure of the compressor should be 0.15-0.2MPa higher than the suction pressure.

◆ The lubricating oil temperature is above 45 ℃, and the temperature of the oil pump is between 60-70 ℃. If it is higher than 83 ℃, the unit will stop automatically.

◆ Water resistance of condenser is 0.06-0.07MPa, water resistance of evaporator is 0.05-0.06MPa.

◆ The unit runs smoothly without abnormal noise and vibration.

◆ The voltage and current are consistent with the unit's voltage and current. Too high or too low will affect the safe operation of the chiller.