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Zhejiang Yinjia Copper Co., Ltd.
was set up in 2004.

Yinjia was established in 2004 with a registered capital of 55.6 million Yuan, located in the southeast of Zhejiang Province, China, 80KM from Hangzhou and 70KM from Ningbo, our factory covers an area of 24,000 square meters and has 240 manufacturing staff. We have also obtained the "Copper Pipe Production License" issued by the General Administration of Quality Supervision and Inspection of China and passed the ISO9001:2008 international quality management system certification.

As China Refrigeration Capillary Tubes Manufacturers and Factory, Yinjia specializes in the production of precision purple copper tubes, purple copper pipeline components and steel pipe pipeline components. The main products are: copper pipe assemblies, connecting pipes, bellows, silencers, four-way valve pipe assemblies for air conditioners, suction and discharge pipes applied to compressors, high-efficiency copper pipes for heat exchangers, etc. The products we produce are widely used in the air conditioning, refrigeration and heat exchanger industries and are well evaluated by our customers.

In 2014, Yinjia's sales of copper materials reached 1500 tons, and the output of products reached 80 million pieces, with an output value of 28,000,000 RMB. The company takes the market as the guide and strengthens the internal management, reform and innovation, implements 6S management, lean production, constantly restructuring, and improves the quality of products and services. Supply Refrigeration Capillary Tube Custom

With the tenet of "customer first, quality first", the company is dedicated to providing customers with satisfactory products and considerate services.
  • 24,000

    Plant area

  • 150

    Manufacturing staff

  • 230+


  • 300,000

    Daily output



  • ISO 9001:2015

  • ISO 9001:2015

  • Invention Patent Certification

  • High and New Technology Enterprise Certification

Industry knowledge
How do capillary tubes contribute to the process of refrigerant expansion within the system?
Refrigeration Capillary Tubes play a crucial role in the refrigeration cycle by facilitating the expansion of high-pressure liquid refrigerant into a low-pressure mixture of liquid and vapor. Here's how capillary tubes contribute to the process of refrigerant expansion within the system:
Restriction of Flow: Capillary tubes are designed with a very narrow and long passage, which restricts the flow of liquid refrigerant. This restriction results in a significant pressure drop along the length of the tube.
Pressure Drop: As the high-pressure liquid refrigerant enters the Refrigeration Capillary Tubes, it experiences a substantial pressure drop. This pressure reduction is due to the tube's small diameter and length, which creates a resistance to flow.
Flash Evaporation: The pressure drop causes the liquid refrigerant to undergo flash evaporation. This means that a portion of the liquid rapidly vaporizes, turning into a mixture of low-pressure vapor and liquid.
Temperature Drop: The sudden vaporization of the liquid refrigerant absorbs heat from the surroundings, including the remaining liquid refrigerant in the tube. This leads to a drop in temperature within the capillary tube.
Superheat Control: Capillary tubes also help control the superheat in the evaporator coil. Superheat is the difference between the temperature of the refrigerant vapor and the temperature at which it would completely vaporize. Capillary tubes are designed to provide a specific amount of superheat, which ensures that the evaporator operates effectively.
Delivery to Evaporator: The refrigerant in the form of a low-pressure mixture of vapor and liquid is delivered to the evaporator coil. In the evaporator, the refrigerant absorbs heat from the surrounding air or space, causing it to fully vaporize.
Cooling Effect: During the vaporization process in the evaporator, the refrigerant extracts heat from the environment, providing the cooling effect required in the refrigeration cycle.
Cycle Continuation: The refrigerant vapor exits the evaporator and is drawn into the compressor, where it is compressed to a high pressure and temperature. The cycle then repeats.
Capillary tubes are particularly effective at precisely controlling the flow of refrigerant and the expansion process. The length and diameter of the capillary tube, as well as the choice of refrigerant, are carefully selected to ensure that the evaporator operates at the desired temperature and that the superheat remains within the required range. This control is essential for maintaining the efficiency and performance of the refrigeration system.
how a refrigeration capillary tube works
Function as an Expansion Device: The primary function of the capillary tube is to serve as an expansion device, which means it allows the high-pressure liquid refrigerant to expand rapidly as it enters the low-pressure side of the system. This expansion causes a drop in pressure and temperature of the refrigerant.
Pressure Drop: The capillary tube has a small internal diameter, and its length is designed to create a significant pressure drop as the refrigerant flows through it. The pressure drop occurs because of the restriction caused by the narrow diameter of the tube, which helps to regulate the flow rate of the refrigerant.
Rapid Cooling: As the high-pressure liquid refrigerant passes through the capillary tube and expands into the low-pressure side, it undergoes a rapid cooling process. This cooled refrigerant then enters the evaporator coil in the indoor unit of the air conditioner or refrigeration system.
Evaporation and Heat Absorption: Inside the evaporator coil, the low-pressure, low-temperature refrigerant absorbs heat from the surrounding air, causing the air to cool down. This cooled air is then blown into the room for air conditioning purposes or used to maintain the desired temperature in refrigeration applications.
Return to the Compressor: After absorbing heat in the evaporator, the low-pressure refrigerant, now in the form of a gas, returns to the compressor, where the refrigeration cycle starts over.
The use of a capillary tube as an expansion device is common in small, compact refrigeration and air conditioning systems, such as domestic refrigerators, window air conditioners, and some small commercial refrigeration units.

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