Application of stainless steel composite water pipes in solar water heaters
At present, solar water heaters on the market are mainly made of galvanized pipes. Although galvanized pipes have good strength and stiffness, they can produce rust due to long-term exposure to water sources. Over time, rust can adsorb on the collector pipes, affecting heat transfer efficiency, and rust can also affect people's health. Some pipes with plastic are sensitive to temperature differences. If the pipe length is 10 meters and the temperature difference is 40 degrees (temperature difference between cold and hot water), the expansion length of the plastic pipe can reach 28MM. By using stainless steel composite water pipes, the above-mentioned problems can be avoided. The inner layer of stainless steel composite water pipes is made of stainless steel to avoid internal rust; Because both the stainless steel layer and the galvanized pipe are metal, their thermal expansion coefficient is basically the same, and the composite is quite dense, thus avoiding the detachment of the stainless steel layer. The user feedback was very good after use.
1、 Introduction to Stainless Steel Composite Water Pipe
1. Stainless steel composite water pipe composite pipe is made of corrosion-resistant stainless steel pipe and high-strength galvanized steel pipe, which are composite together through special processing technology. Its inner layer is food grade stainless steel with a wall thickness of over 0.35mm as the corrosion resistant layer, and the outer layer is galvanized steel pipe within the national standard as the main load-bearing body. This makes the stainless steel composite water pipe not only have the corrosiveness of stainless steel, but also have the high strength and rigidity characteristics of galvanized steel pipe.
2. Composite Theory of Stainless Steel Composite Water Pipe
The composite theory of stainless steel composite water pipes is based on the tensile yield theory of metal materials. In stainless steel composite water pipes, the material of galvanized steel pipes is Q235, and stainless steel is 0Cr18Ni9. Based on the tensile curve of Q235 and the tensile curve of stainless steel with only one-fifth of the thickness of Q235, we also add an instantaneous suitable external force. Under this external force, when the stainless steel reaches the yield stage, Q235 is still in the elastic deformation stage. After the external force is removed, the shape of Q235 is restored, but stainless steel that has reached the yield stage and deformed cannot restore its original shape. In addition, the cold work hardening of stainless steel is quite sensitive, which effectively combines the two together through interference.
According to experiments, Q235 shows no significant change in the mechanical properties of the material under long-term load at temperatures below 250-300 degrees Celsius. That is to say, after the external force is removed, there is always a force in Q235 that allows the stainless steel composite water pipe to shrink and composite together. In addition, stainless steel, due to the compact cubic lattice of austenite, has a small diffusion rate and a slow deceleration of the second phase. It has far from reaching the softening temperature at 600 degrees Celsius, and has good thermal strength. It is also difficult to recrystallize below 600 degrees Celsius. It can be said that the stainless steel of stainless steel composite water pipes will not change below 600 degrees Celsius.
The melting point of the galvanized layer is 380 degrees, which is very stable below 320 degrees. Therefore, in the future use process, as long as the temperature does not exceed 300 degrees, stainless steel pipes and galvanized pipes will always be composite together.
1、 Introduction to Stainless Steel Composite Water Pipe
1. Stainless steel composite water pipe composite pipe is made of corrosion-resistant stainless steel pipe and high-strength galvanized steel pipe, which are composite together through special processing technology. Its inner layer is food grade stainless steel with a wall thickness of over 0.35mm as the corrosion resistant layer, and the outer layer is galvanized steel pipe within the national standard as the main load-bearing body. This makes the stainless steel composite water pipe not only have the corrosiveness of stainless steel, but also have the high strength and rigidity characteristics of galvanized steel pipe.
2. Composite Theory of Stainless Steel Composite Water Pipe
The composite theory of stainless steel composite water pipes is based on the tensile yield theory of metal materials. In stainless steel composite water pipes, the material of galvanized steel pipes is Q235, and stainless steel is 0Cr18Ni9. Based on the tensile curve of Q235 and the tensile curve of stainless steel with only one-fifth of the thickness of Q235, we also add an instantaneous suitable external force. Under this external force, when the stainless steel reaches the yield stage, Q235 is still in the elastic deformation stage. After the external force is removed, the shape of Q235 is restored, but stainless steel that has reached the yield stage and deformed cannot restore its original shape. In addition, the cold work hardening of stainless steel is quite sensitive, which effectively combines the two together through interference.
According to experiments, Q235 shows no significant change in the mechanical properties of the material under long-term load at temperatures below 250-300 degrees Celsius. That is to say, after the external force is removed, there is always a force in Q235 that allows the stainless steel composite water pipe to shrink and composite together. In addition, stainless steel, due to the compact cubic lattice of austenite, has a small diffusion rate and a slow deceleration of the second phase. It has far from reaching the softening temperature at 600 degrees Celsius, and has good thermal strength. It is also difficult to recrystallize below 600 degrees Celsius. It can be said that the stainless steel of stainless steel composite water pipes will not change below 600 degrees Celsius.
The melting point of the galvanized layer is 380 degrees, which is very stable below 320 degrees. Therefore, in the future use process, as long as the temperature does not exceed 300 degrees, stainless steel pipes and galvanized pipes will always be composite together.
