Often used in electrical, industrial and construction industries, copper tubes can be produced by extrusion, continuous casting and rolling, and up-drawing methods. Copper Tube is an important raw material for manufacturing of refrigeration unit. 

(1)Make a heat exchanger; 

(2)Make Connection Pipes and fittings;

1.General Air Conditioning: The thickness is generally 2 minutes, 3 minutes 0.5 mm thick, 4 minutes 0.6 mm thick, 5 minutes and 6 minutes 0.7 mm thick. Mainly for R22.

Non-fat air conditioning copper pipe: also known as "oil-free air conditioning copper pipe" , there are 2 points, 3 points is 0.8 mm thick, 4 points, 5 points, 6 points is 1.0 mm thick. Mainly used in refrigerant such as R410. 2. SPECIFIC CLASSIFICATION OF COPPER PIPE MATERIALS FOR AIR-CONDITIONING: oxygen-free Copper: including high-purity oxygen-free copper (TU0, TU1, TU2) and phosphorus-oxygen-free copper (TUP, TP1, TP2, etc.) , which is characterized by very little oxygen content and a small amount of deoxidizer remaining in the oxygen-free copper; Oxygen Copper: mainly ordinary pure copper (T1, t2, T3, etc.) and tough copper, characterized by high oxygen content; special copper: Arsenic Copper, silver copper, tellurium copper, etc. , characterized by the addition of different trace alloying elements, respectively, in order to improve the comprehensive performance of materials. Now let's focus on copper and brass. Copper Tube: The copper tube used in our refrigeration industry has a copper content of over 99.90% . It has the good characteristics of copper metal, which is a high quality base metal. It is widely used in various fields of industry and civil, and plays an important role. There are three main types of TP2, T2 and TU1. TP2 is dephosphorized copper, containing 0.015-0.04% phosphorus, with good welding and cold bending properties. It is widely used in the manufacture fields of air conditioning and refrigeration connecting pipe, stove gas connection pipe, electric heating pipe and so on. T2 is pure copper, the copper content is higher than 99.90% , when the customer has the high electric conductivity request to the material, the T2 copper tube will be the first choice. TU1 is oxygen-free copper, copper content ≥99.97% , oxygen and impurity content very low, high purity, excellent conductivity, thermal conductivity, good ductility, processing performance and welding, corrosion resistance, cold resistance are good. Because of the high demand and high cost of its production, the price of its products is much higher than other categories of copper pipe. BRASS: copper-zinc Alloy Tube, the number after the letter h in the brand often represents its copper content of the middle value, zinc content for the remaining amount. Brass tubes of different brands, with higher and higher copper content, generally show better quality and extensibility. The utility model is mainly used as a water pipe and a connecting piece for wading.

In general, the appearance of copper tubes should be observed to judge. The first thing is to see the color and lustre of copper tubes. Different color judgments should be made according to the type of copper tubes purchased, such as copper tubes, the Red Copper of general color is good copper, inferior copper inside has impurity. 2, generally good copper pipe is made of pure copper processing, will have better elongation, so high-quality copper pipe will have a deep line. After the inside of the copper pipe, if and the outer wall is the same, it shows that the overall quality of the copper pipe is relatively high. But if the color or other aspects of the time is different, it is likely that some of them have been added in some of these materials such as iron. However, the better copper pipe used in the military industry and its special industry more. 3. Generally processed and shaped copper tubes are mainly divided into hard, semi-hard and soft state. The flexibility of different forms is also different. Generally, the quality of copper tubes can be determined by bending them, but if it is difficult to bend or there will be cracks after bending, indicating that the quality of copper pipe is not too good. CONCLUSION: the high-quality copper pipe has strong plasticity, the poor-quality copper pipe has no metallic luster, the surface is easy to Scab, and the surface is easy to appear pits, holes and so on. 

3.Calculation formula of weight and length of TP2 copper tube for air conditioning

Weight per meter (KG/M) = 0.02796 wall thickness (mm)(outer diameter-wall thickness)(mm) length per kilogram (m/kg) = 1/m weight 

source: Encyclopedia of Refrigeration