Heat Exchanger U Bend Tube

U-tube heat exchanger is a kind of shell-and-tube heat exchanger, which is a typical process equipment commonly used in petrochemical production. With the enlargement of petrochemical equipment and the development of thermal power and nuclear power technology, the U-tube heat exchanger has good thermal compensation performance, good heat transfer performance, strong pressure bearing capacity, simple structure, easy maintenance and cleaning, with other advantages, the U tubes have been more widely used.

However, because the tubes in the middle part of the tube bundle are difficult to replace, and the U-shaped heat exchange tubes are prone to ellipticity and residual stress during the bending process, which will affect the service life of the heat exchange tubes. Therefore, according to the requirements of the standard, when there is a requirement for stress corrosion resistance or the elimination of residual stress, after the carbon steel and low alloy steel U-shaped heat exchange tube bends are qualified, the bend section and the straight pipe section of at least 150mm should be eliminated. Stress heat treatment. After heat treatment, the hydraulic test is carried out one by one to ensure the performance of the heat exchange tubes.

A small amount of scale on the surface of the heat exchange tube has no effect on the performance of the heat exchange U Bend tube.

A small amount of scale will appear on the surface of the heat exchange tube after heat treatment, and the outer side of the elbow section is slightly more than the rest of the scale. Due to the tensile stress on the outside of the heat exchange tube during the bending process, the oxide skin on the outer surface of the bent pipe section is not as dense as before the bent pipe, so iron will diffuse to the surface layer during heat treatment; on the contrary, oxygen will go into the metal through the oxide skin film Diffusion, so as to further oxidize and form a thicker scale, and part of the scale will fall off under the action of surface residual stress.

With reasonable heat treatment parameters and heat treatment methods, the release of residual stress and uniform precipitation of carbides after cold bending of the heat exchange tube makes the structure of the bent pipe section relatively uniform, the hardness value is not much different, the chemical composition does not change, and the mechanical properties meet the requirements. . After heat treatment, a small amount of scale on the surface of the heat exchange tube has no effect on its mechanical properties and tissue composition.

The biggest advantage of the U-bend Tube is that the bending machine can be adjusted to bend a variety of U-bends with different radii and specifications. When the U-bend is used on a moving device, It is directly installed outdoors, and the air chambers of each section are welded to each other with iron plates, and an air regulating plate is installed on each section.

We can bend the tube at variety of radius based on sets of mould series, the material can be seamless carbon steel tube, welded carbon steel tube, stainless steel seamless tube, stainless steel welded tube, alloy tube and titanium tube.

Vertical separators is provided for each radius, horizontal separators for each layer tube

Plastic caps is applied on ends of tubes to protect tube from corrosion

Standard wooden case or welded steel frame with thick plywood case

Bending method and effect of U Bend Tube

Directly install the mold assembly of the U-bend on the operating platform, insert the pipe fittings that need to be bent directly into the pipe mold, or the middle position between the movable clamp and the roller, then tighten the eccentric shaft, and use the wrench Properly rotate the rod to ensure that the screw can clamp the pipe through the movable frame, and then rotate the pipe mold of the roller frame to manufacture U-shaped elbow products.

Difficulties in bending U Bend Tube

When processing and manufacturing the heat exchange tubes of U-shaped elbows, because its resilience will be affected differently due to factors such as the diameter, wall thickness and material of the tube, it is difficult to control the overall resilience Yes, but we can test the radius of the pipe bending die, record the relevant data, and put it into production after debugging.

Through the adjustment of the U-shaped pipe bending machine, various U-shaped pipes of different shapes can be manufactured and produced, and the key is different in the effect of use, or the performance and occasion are different, mainly according to the raw material of the bent pipe To determine the final use effect, but the most important thing is the selection of the pipe bender.

Although the U-shaped elbow does not need to undergo thermal plastic compression during the entire forming process, there will be residual stress on the inner section, which will cause varying degrees of damage to the entire or local elbow. Influence; and the cold-rolled U-bend pipe is basically an open cross-section in the pipe style, so the stiffness of the free torsion of the cross-section is relatively low.

Q: Are you trading company or manufacturer?

A: We are professional manufacturer of steel tube, stainless steel tube, U Bend Tube and also finned tubes.

Q: Do you provide samples in free?

A: Yes, samples in short cut can be provided freely but with courier cost collected. Or customer pay us the courier cost first and then we return it from future orders.

Q: Do you accept the third party inspection?

A: Yes, we always cooperate with SGS, TUV, BV and other inspection party customer pointed.

Q: How your company guarantee the quality?

A: Each product is manufactured by certified operators under company’s strict quality policy, we have QA/QC standard and can issue warranty annex to our customers.