Material preparation before installation
The cold storage equipment materials should be equipped according to the cold storage engineering design and construction material list. The cold storage panels, doors, refrigeration units, refrigeration evaporators, microcomputer temperature control boxes, expansion valves, connecting copper pipes, cable control lines, storage lights, sealants, installation auxiliary materials, etc. should be complete and the material and accessory models should be checked.
Installation of the cold storage panel
When assembling the cold storage as a whole, there should be a gap between the wall and the roof. The cold storage floor should be installed flat, and the uneven ground should be leveled with materials, and the locking hooks between the panels should be locked, and sealed with silicone to achieve a flat surface without a hollow feeling. After the top plate, floor, and vertical plate of the cold storage body are installed, the top and vertical, vertical and floor should be aligned and locked, and all the locking hooks between each other should be fixed.
Evaporator installation technology
When choosing the hanging point, first consider the best position for air circulation, and then consider the direction of the warehouse structure.
The gap between the cooler and the warehouse plate should be greater than the thickness of the evaporator.
All the hangers of the cooler should be tightened, and the bolts and hanger holes should be sealed with sealant to prevent cold bridges and air leakage.
When the ceiling fan is too heavy, use 4- or 5-angle iron as a beam, and the beam should span across another top plate and wall plate to reduce the load.
Assembly and installation technology of refrigeration units
Semi-hermetic or fully hermetic compressors should be equipped with oil separators, and appropriate amount of oil should be added to the oil separator. When the evaporation temperature is lower than -15℃, a gas-liquid separator should be installed and appropriate amount of refrigeration oil should be added.
The compressor base should be installed with a shock-absorbing rubber seat.
The installation of the unit should leave maintenance space to facilitate observation of instrumentation and valve adjustment.
The high-pressure gauge should be installed at the three-way of the liquid storage valve.
The overall layout of the unit is reasonable and the color is consistent.
The installation structure of each model of unit should be consistent.
Refrigeration pipeline installation technology
The selection of copper pipe diameter should be strictly in accordance with the compressor suction and exhaust valve interface. When the condenser is separated from the compressor by more than three meters, the pipe diameter should be increased.
The suction surface of the condenser should be kept at a distance of more than 400mm from the wall, and the outlet should be kept at a distance of more than three meters from the obstacle.
The inlet and outlet diameters of the liquid storage tank shall be based on the exhaust and liquid outlet diameters indicated on the unit sample.
The compressor suction pipeline and the air cooler return pipeline shall not be less than the size indicated in the sample to reduce the internal resistance of the evaporation pipeline.
When making the regulating station, each liquid outlet pipe should be sawed into a 45-degree bevel and inserted to the bottom, and the liquid inlet pipe should be inserted into one-fourth of the diameter of the regulating station.
The exhaust pipe and the return pipe should have a certain slope. When the condenser is higher than the compressor, the exhaust pipe should be sloped toward the condenser and a liquid ring should be installed at the compressor exhaust port to prevent the gas from cooling and liquefying after shutdown and flowing back to the high-pressure exhaust port, causing liquid compression when restarting.
A U-bend should be installed at the outlet of the return air pipe of the air cooler. The return air pipe should slope toward the compressor to ensure smooth oil return.
The expansion valve should be installed as close to the air cooler as possible, the solenoid valve should be installed horizontally, the valve body should be vertical and pay attention to the direction of liquid discharge.
If necessary, install a filter on the return air pipe of the compressor to prevent dirt in the system from entering the compressor and remove moisture in the system.
Before tightening all the nuts and locknuts in the refrigeration system, apply refrigeration oil for lubrication to enhance the sealing performance. After tightening, wipe them clean and lock the packings of each gate.
The expansion valve temperature sensing package is fastened with a metal clip at 100mm to 200mm from the evaporator outlet and wrapped tightly with double-layer insulation.
After the refrigeration system is installed, it should be beautiful as a whole and have consistent colors. There should be no uneven height of the pipe crossing.
When welding the refrigeration pipeline, a sewage outlet should be left. Use nitrogen to blow from high and low pressure to blow in sections. After the section blowing is completed, the whole system is blown until no dirt is seen. The blowing pressure is 0.8MP.
Installation technology of electric control system
Mark the wire number of each contact for maintenance.
Make the electric control box strictly according to the requirements of the drawing, and connect it to the power supply for no-load test.
Mark the name on each contactor.
Fix the wires of each electrical component with binding wire.
Compress the wire connector of the electrical contact and the main wire connector of the motor with a wire clamp, and tin it when necessary.
Lay the wire tube for each equipment connection and fix it with a clamp. Use glue to glue the PVC wire tube and seal the pipe mouth with tape.
The distribution box is installed horizontally and vertically, with good environmental lighting and dry indoors for easy observation and operation.
The area occupied by the wire in the wire tube shall not exceed 50%.
The selection of wires must have a safety factor, and the temperature of the wire surface shall not exceed 40 degrees when the unit is running or defrosting.
The circuit system must be a 5-wire system, and a ground wire must be installed if there is no ground wire.
The wire should not be exposed to the open air to avoid long-term sun and wind aging of the wire skin, short circuit leakage and other phenomena.
The wire pipe installation should be beautiful and firm.
After the whole system is welded, an air tightness test should be carried out. The high-pressure end should be filled with 1.8MP nitrogen. The low-pressure end should be filled with 1.2MP nitrogen. During the pressurization period, soapy water should be used for leak detection. Each weld, flange and valve should be carefully checked. After the leak detection is completed, the pressure should be maintained for 24 hours without pressure drop.
Refrigeration system fluorine addition debugging system
Measure the power supply voltage.
Measure the three winding resistance values of the compressor and the insulation of the motor.
Check the opening and closing of each valve in the refrigeration system.
After evacuating, inject refrigerant into the liquid storage tank to 70% to 80% of the standard filling amount by weight, and then operate the compressor to add gas from low pressure until it is sufficient.
After starting up, first listen to whether the sound of the compressor is normal, check whether the condenser and the air cooler are running normally, and whether the three-phase current of the compressor is stable.
After normal cooling, test various parts of the refrigeration system, exhaust pressure, suction pressure, exhaust temperature, suction temperature, motor temperature, crankcase temperature, and temperature before the expansion valve, observe the frosting of the evaporator and expansion valve, observe the oil level and color change of the oil mirror, and whether there is any abnormality in the sound of the equipment operation.
Set the temperature parameters and the opening degree of the expansion valve according to the frosting and use of the cold storage.
Guangxi Cooler Refrigeration Equipment Co.,Ltd.
Tel/Whatsapp:+8613367611012
Email:karen@coolerfreezerunit.com
Post time: Aug-08-2024