Stainless steel has proven to be a particularly reliable and durable material here. Heat exchangers made of stainless steel are particularly resistance to corrosion and deposits of limestone and other residues are minimised. Viesel heat exchangers have been made of only stainless steel for over 50 years.
Common tube bundle heat exchangers and special heat exchangers can be realised using stainless steel without problem. If single parts are welded to each other, each welded seam always marks a possible weak spot. Always rely on an experienced manufacturer due to reasons of reliability during operation. We have the necessary expertise and experience to perform welded seams cleanly and reliably according to the WIG and/or MIG procedure. Naturally we are certified according to DIN EN ISO 3834-3:2005.
304/ 316 Stainless Steel U Tube And ASTM A213 Finned Tube
Exchanger tubes are very popular in the boiler and heat exchanger industry, water heater industry, air conditioning industry, etc. Stainless steel heat exchanger tubes have many properties such as corrosion resistance, good ductility, lightweight, fatigue resistance, low and high-temperature resistance. The stainless steel tube heat exchanger is suitable for transporting all kinds of gases and liquids with extremely low and high-temperature requirements. They are also known as stainless steel spiral heat exchanger.
Stainless Steel Tube Coil heating exchanger is serpentine grade 316 stainless steel tube heat exchanger or 304 Stainless Steel. This heating exchanger has excellent corrosion resistance to most chemicals, salts, and acids. The main advantage is to circulate liquid, vapor, refrigerant with low pressure, very high-efficiency heat exchange, no leakage and resistance to high pressures. Stainless steel U tube is U-shaped tube heat exchangers are designed for high-temperature applications, especially hot oil or steam condensing systems. These stainless steel Utubes are sold in many industries/markets, due to their overall corrosion resistance and good machinability.
They are used for heat exchanging, in the field of Chemistry and Petrochemicals, Energy production, Recycled energy, Pulp and paper industry, Industrial pipelines, Mechanical work, Pharmaceutical / Petrochemical, Food and Beverage Industry. Corrugated stainless steel tubing heat exchanger are Stainless steel corrugated pipes, they are shaped like spiral grooved stainless steel pipes and are obtained from the smooth pipe by cold forming. It can be used for the connection of soft and flexible stainless steel pipes and has features such as good protective displacement and low vibration and noise.
High and low-temperature high pressure Resistant to a variety of delivery media, the hose can operate at high-pressure hydrothermal water, high-temperature steam, high-pressure hydrothermal compression distribution temperature gases, oils, organic solvents, corrosive liquids gas. On other hand, media widely used Stainless steel heat exchangers are particularly advantageous because they do not require the use of system inhibitors and are, in fact, compatible with clean running water. This means that little maintenance is needed to keep the stainless steel heat exchanger in good condition. Stainless steel U-bending pipes and tubes are used to prevent emissions due to applications.
In refinery applications, these carbon steel U-bend pipes and tubes also prevent the mixing of gases with other harmful gases and from escaping to the exterior surface through the drainage system. Stainless steel Finned tubes are a range of tubes used in applications involving the transfer of heat from a hot liquid to a cold liquid through the pipe wall. In other words, finned tubes use their “fins” to increase the area that the external fluid is exposed to. The tube then exchanges heat between the fluid inside the tube and the fluid outside the tube.
A More Efficient Exchange
Benefits for Using Murphy Technology to Produce Shell and Tube Heat Exchangers
Murphy finned tubes is selling tubing and offering license opportunities for their new, patented Martensitic Stainless Steel (MS3) tubing for heat exchanger applications. Benefits include: increased performance, increased thermal conductivity and heat transfer, better wear resistance, and reduced costs with 410 Martensitic Stainless Steel tubing.
410 Stainless Steel tubing offers significantly increased heat transfer and strengths, as well as a reduction in thermal expansion, when compared to typical austenitic Stainless Steel tubing grades such as 316L.
Thermal conductivity of 410 Stainless Steel tubing is 53% BETTER at the same wall thickness than 316L tubing (410 k=24.9 W/m-K; 316L k=16.3 W/m-K @ 100 degrees centigrade). Engineers will appreciate the ability to reduce the wall thickness of 410 Stainless Steel within their heat exchanger designs, while still maintaining burst pressure requirements. Overall heat transfer can be improved an additional 400% in hardened 410 designs relative to conventional heavy-wall 316L heat exchangers rated for identical maximum pressures.
Thermal stresses are also reduced as 410 has a Coefficient of Thermal Expansion (CTE = 9.9 um/m/K) 38% less than 316L (CTE = 15.9 um/m/K). As a result, thermal fatigue stresses are reduced and product durability is increased.
The introduction of 410 Martensitic Stainless Steel for the fabrication of heat exchanger tubing offers higher strength, increased hardness and wear resistance, as well as a lower cost alternative to Ferritic series Stainless Steel alloys, which include 410S.
The hardened strength of 410 Martensitic Stainless Steel is twice that of 410S. Heat exchanger tubing made out of 410 Stainless Steel will allow for thinner walled material to carry the same pressures, increasing heat transfer and making the heat exchanger much more effective. Using less material also reduces overall costs per tube, heat exchanger fabrication and shipping costs.
Heat Exchanger Basics:
A shell and tube heat exchanger is just one type of heat exchanger design. It is suited for higher-pressure applications and markets such as: dairy, brewing, beverage, food processing, agriculture, pharmaceutical, bioprocessing, petroleum, petrochemical, pulp & paper, and power & energy.
As its name implies, this type of heat exchanger consists of an outer, elongated shell (large pressure vessel or housing) with a bundle of smaller diameter tubes located inside the shell housing. One type of fluid runs through the smaller diameter tubes, and another fluid flows over the tubes (throughout the shell) to transfer heat between the two fluids. The set of tubes is called a tube bundle, and may be composed of several types of tubes; round, longitudinally finned, etc. depending on the particular application and fluids involved.
There may be variations on the shell and tube design. Typically, the ends of each tube are connected to plenums or water boxes through holes in the tubesheets. The tubes may be straight or bent in the shape of a U, which are called U-tubes.
The selection of material for tubing is extremely important. To be able to transfer heat well, the tube material should have good thermal conductivity. Because heat is transferred from a hot to a cold side through tubes, there is a temperature difference through the width of the tubes. Because of the tendency of the tube material to thermally expand differently at various temperatures, thermal stresses occur during operation. This is an addition to any stress from high pressures from the fluids themselves. The tube material also should be compatible with both the shell and tube side fluids for long periods under the operating conditions (temperatures, pressure, pH, etc.) to minimize deterioration such as corrosion. All of these requirements call for careful selection of strong, thermal conductive, corrosion-resistant, high-quality tube materials. Typical metals used in the manufacturing of heat exchanger tubing include: carbon steel, stainless steel (austenitic, duplex, ferritic, precipitation-hardenable, martensitic), aluminum, copper alloy, non-ferrous copper alloy, Inconel, nickel, Hastelloy, tantalum, niobium, zirconium, and titanium.
Stainless Steel Shell And Tube Heat Exchanger
The tubes used in heat exchanger systems work towards the transference of heat between two fluids or they may be involved in cooling processes in said applications. Moreover, many Stainless Steel Shell And Tube Heat Exchanger Manufacturers recommend them because they offer their user several benefits. In industries, a Stainless Steel Heat Exchanger Tube may be used in various operations ranging from the elimination of process heat and feed water preheating to the Evaporation process for liquid or steam. The high performance of the alloy, in combination with its corrosion resistance properties and high strength, makes the Spiral Heat Exchanger Manufacturers recommend their use to various industries such as the marine industry as well as applications involving hydraulics.
In hydraulic applications, Plate And Frame Heat Exchanger Manufacturers suggest using these tubes for the cooling of hydraulic and lube oil. In addition to the above mentioned tasks, the Stainless Steel Heat Exchanger Shell And Tube may be employed in applications such as the cooling of the turbine, compressor, and engine along with the condensation process vapor or steam. While Air Cooled Heat Exchanger Manufacturers have several options like copper, copper-nickel, carbon steel, brass alloys, or even titanium alloys to choose from, they prefer using stainless steel.
Since stainless steel is easily available, and they offer their user resistance to corrosion, the Stainless Steel Fin Tube Heat Exchanger may be manufactured in any grade, depending on the needs of the application. If, however, the need of the application is to lower the cost, the Stainless Steel Heat Exchanger Tube Suppliers may advise the buyer to purchase an exchanger tube produced from grade 304, which is an economical grade of stainless steel
Shell and tube heat exchangers
This type of heat exchanger is used for transferring heat in order to obtain the appropriate temperature parameters of the media flowing through the heat exchanger.
We provide services of production of heat exchangers on the basis of the documentation received from the customer.
We are specialized in the production of shell and tube heat exchangers made of stainless steel.
We are capable of manufacturing heat exchangers that reach the mass of 20 tons and include more than 7,000 pipes welded on the floor tube sheet.
The aspect that distinguishes our offer is the fact of subjecting the entire heat exchanger under process of degreasing, pickling, passivation, rinsing and drying in a technological line specially adapted for this type of operation.
Performing this process ensures the elimination of corrosion processes and prolonged use of the device. For high demanding customers our heat exchangers are subjected to a process of shot peening with quartz beads.
After welding procedures, the heat exchanger ensures the tightness of 10-6 mbar l/s.
Leak test is performed with a helium detector. Exchangers are also subjected to leak test the water pressure control calculated individually for each project.
Heat exchangers are also subjected to water leak proof test pressure control which is calculated individually for each project.
The Use of Stainless Steel Tubing in Heat Exchanger Service
What is Stainless Steel Tube?
Stainless steel tube is a versatile structural material that may be utilized in a variety of ways. Stainless steel tube is widely utilized in a variety of industries, and their sizes and variations vary greatly based on the application requirements. Stainless steel has proved to be a very dependable and long-lasting material in this application. Stainless steel heat exchangers are very corrosion resistant, and deposits of limestone and other residues are reduced. Boiler and heat exchanger manufacturers, as well as water heater and air conditioning manufacturers, use exchanger tubes extensively. Corrosion resistance, ductility, lightweight, fatigue resistance, and low and high-temperature resistance are only a few of the benefits of stainless steel heat exchanger tubes. The stainless steel tube heat exchanger can carry a wide range of gases and liquids at extremely low and high temperatures. Stainless steel spiral heat exchangers are another name for them.
- A stainless steel U tube is a particular shaped tube that is utilized in high heat and pressure applications. These are used to prevent welding connections from forming a curve or a direction change.
- The fins on the surface of the pipes are utilized to release heat from the Stainless Steel Fin Tube Heat Exchanger.
- Heat transmission is substantially more efficient as a result of this than with standard Stainless Steel Heat Exchanger Tubing. Materials engineers have a variety of alternatives to increase the performance of heat exchanger tubes.
- They include requesting better corrosion-resistant grades, choosing tube suppliers with improved tube production and finning techniques, and relying on cutting-edge manufacturers with improved non-destructive testing methods.
- The stainless steel tube heat exchanger is ideal for moving a wide range of gases and liquids at both low and high temperatures.
- Stainless steel is a durable material. Heat exchangers with a U-shaped tube are suited for high-temperature applications, such as hot oil or steam condensing systems.
- They are employed in the fields of chemistry and petrochemistry, energy production, recycled energy, pulp, and paper industry, industrial pipelines, mechanical work, pharmaceutical/petrochemical, food and beverage industry, and industrial pipelines.
- Stainless steel heat exchangers are especially useful since they do not require system inhibitors and are compatible with clean running water. This implies that the stainless steel heat exchanger requires very little maintenance to be in good working order. To avoid leaks from applications, stainless steel U-bending pipes and tubes are utilized.
The Use of Duplex Stainless Steel Tubing in Heat Exchanger Service
To improve the performance of your industrial process heat exchanger, consider using duplex stainless steel tubing.
Heat exchangers are key components for many industries, particularly in chemical and oil and gas plants where they play a vital role in process control. Industry professionals — from design engineers and fabricators to the in-plant operators who work with the equipment daily — seek new ways to improve heat transfer performance and extend the life of these units in corrosive environments. Many times, improvements are closely related to the tubing specified for use in their heat exchangers. To improve the performance of heat exchanger tubing, materials engineers have a number of options. They include specifying higher corrosion-resistant grades, selecting tube suppliers with enhanced tube manufacturing and finning processes and using state-of-the-art manufacturers that have upgraded their methods of non-destructive testing.
Making the correct decision is not an easy task. When selecting a tube material for a heat exchanger, many different options are available, depending upon the application, design and operating conditions (such as temperature, pressure and the corrosive environment). In addition, to be viable candidate materials, those tubing options need to be available and affordable. Everything from raw material costs to the availability of off-the-shelf distribution can impact the tube selection process. And, all of these factors have the potential to affect the outcome of a project.
The table above provides a summary of some of the more frequently used ASME specifications for steel tubing for pressure applications. (To view this image larger and in a new window, click here. ) It shows the wide range of alternatives that engineers and fabricators are faced with when considering candidate tubing materials for heat exchanger, condenser, boiler and feedwater heater service.
Duplex stainless steels refer to a family of stainless steels alloyed to produce a microstructure consisting of approximately equal parts ferrite and austenite.
Heat exchangers are often faced with extreme temperatures, pressures and corrosive media. Duplex stainless steels are designed to have high strengths while maintaining good toughness, have excellent resistance to chloride pitting corrosion and be more resistant to stress corrosion cracking than the 300 series austenitic stainless steels.
There are several groups of duplex stainless steels that are categorized by the level of alloying elements present. Lean duplex stainless steels have low amounts of alloying elements while duplex and super duplex stainless steels have higher amounts of alloying elements. The composition of a duplex stainless steel directly affects the corrosion resistance of the alloy. This is most often quantified by the pitting resistance equivalent number (PREn): PREn = %Cr + 3.3 x %Mo + 16 x %N).
Duplex stainless steels are useful in applications where strength is of great importance. They can help reduce the weight of components due to their increased strengths (about twice as high as typical 300 series austenitic stainless steels). The higher strength equates to thinner sections of duplex stainless steel being required to accommodate a load as opposed to lower strength materials (like carbon or austenitic stainless steels).
By comparison, many alternative stainless steel options fall short in corrosion resistance. For instance, austenitic stainless steels are readily susceptible to stress corrosion cracking under certain conditions. This limits the recommended operating temperatures of austenitic stainless steel components in stress corrosion cracking environments. Conversely, duplex stainless steels are more resistant to stress corrosion cracking and, therefore, can be used in many environments where austenitic stainless steel is not adequate. In fact, duplex stainless steels also have much improved resistance to chloride pitting corrosion as compared to austenitic stainless steels. This is of great importance when trying to find an alloy that is adequate for chloride-containing environments, where austenitic stainless steels are not suited for service.
Strength and corrosion resistance aren’t the only factors that engineers weigh in their decision-making processes. Cost and availability often come into play. Many times, manufacturers and distributors can provide duplex stainless steels at a much more stable price as compared to austenitic stainless steels due to their lower content of nickel and molybdenum. Of course, this offers some protection from the volatility of raw material pricing that other candidate materials face.
As well as it performs in many operating environments, duplex stainless steel tubing does have potential drawbacks and fabrication complexities. It requires much more precise and careful heat treatment plans as compared to austenitic stainless steels due to the tendency to form detrimental intermetallic phases. Inter metallics, which can form in duplex stainless steels, can cause the material to become brittle and impair corrosion resistance. Welding or other fabrication processes that impart high heat inputs into the material can also promote intermetallic phases to form. However, with a proper Welding Procedure Specification (WPS) and heat treating/cooling processes, detrimental intermetallic phases can be avoided.
Duplex stainless steels also have limits on the temperatures in which they can be used in service. They have the tendency to form a low-temperature intermetallic phase (alpha prime), which causes embrittlement of the material. The industry-recommended temperature range that duplex stainless steels can be used at is –22 to 617°F (-30 to 325°C). Welding duplex stainless steels can also be challenging because care must be taken to ensure that the weld has the proper phase balance. The ferrite content of the weld must fall within a specified range provided. If the phase balance of the weld does not fall within the specification, the corrosion and mechanical properties of the weld could be compromised. A proper WPS, which has been verified to yield the proper phase balance, should be used to avoid complications.
Manufacturers who are experienced at working within duplex stainless steels’ limitations are able to maximize their many potential benefits, providing end users with superior performance. Like less corrosion-resistant carbon steel or copper alloy products, duplex stainless steel tube can also be integral finned to improve heat transfer by providing an increase in its surface area.
Finning duplex stainless steels is an extremely challenging process due to the high strength of these materials. Achieving the desired number of fins and fin height without damaging them requires skill, experience and extensive research and development. Heat treatment after the finning or U-bending manufacturing steps also requires precise process control.
Utilizing corrosion-resistant duplex stainless steel tubing in place of traditional carbon steel or austenitic stainless steel can be beneficial to the performance of heat exchangers. These unique alloys have the ability to extend the lifetime of the tubing in the right applications. Yet duplex is not always the answer. Pinpointing the ideal tubing for an application — one manufactured by an experienced supplier that can meet tight turnaround requirements — can be a challenge. But finding that knowledgeable source is well worth the effort because getting the materials-selection process right or wrong impacts everything from budgets to production schedules.