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Murphy Thermal Energy Technology was founded in 1992 and has been committed to the development of titanium tube in HVAC industry.
Guided by customer needs, the company can customize thermal transfer products and thermal energy solutions according to customer needs, which can meet the needs of various customers and undertake the entire project from design, manufacturing to installation.
Our aim is to provide high-quality thermal energy solutions and services for the global thermal energy industry with high-quality products.
DESIGN AND DEVELOPMENT
We focus on providing the most suitable fin tube design for our customers, with a strong design team we make every effort to meet clients requirement.
With strong design team we accept all the OEM and ODM orders. Our production lines include customer’s labels and trademarks.
We manufacture and deliver according to your needs.
The titanium tube is light in weight, high in strength and superior in mechanical properties. It is widely used in heat exchange equipment, such as tube and tube heat exchangers, coil heat exchangers, serpentine tube heat exchangers, condensers, evaporators and transportation pipelines. Many nuclear power industries use titanium tubes as standard tubes for their units.
Why we use titanium tube?
What is titanium
Titanium is an important alloying element in steel and alloys, with metallic luster and ductility. The main characteristics of titanium are low density, high mechanical strength and easy processing. The plasticity of titanium mainly depends on purity. The purer the titanium, the greater the plasticity.
It has good corrosion resistance and is not affected by the atmosphere and sea water. At room temperature, it will not be corroded by hydrochloric acid below 7%, sulfuric acid below 5%, nitric acid, aqua regia or dilute alkali solution; only hydrofluoric acid, concentrated hydrochloric acid, concentrated sulfuric acid, etc. can act on it.
Titanium has plasticity. The elongation of high-purity titanium can reach 50-60%, and the reduction of area can reach 70-80%, but the shrinkage strength is low (that is, the strength generated during shrinkage). The presence of impurities in titanium has a great influence on its mechanical properties, especially interstitial impurities (oxygen, nitrogen, carbon) can greatly increase the strength of titanium and significantly reduce its plasticity.
The good mechanical properties of titanium as a structural material are achieved by strictly controlling the appropriate impurity content and adding alloy elements.
Titanium material features
Low density, high specific strength
The density of titanium metal is 4.51g/cm3, which is higher than aluminum but lower than steel, copper, and nickel, but its specific strength is the first among metals.
Titanium is a very active metal, its equilibrium potential is very low, and the thermodynamic corrosion tendency in the medium is high. But in fact, titanium is very stable in many media. For example, titanium is corrosion-resistant in oxidizing, neutral and weak reducing media.
This is because titanium and oxygen have a great affinity. In the air or in an oxygen-containing medium, a dense, strong adhesion and inert oxide film is formed on the surface of titanium, which protects the titanium matrix from corrosion.
Even due to mechanical wear, it will quickly heal itself or regenerate. This indicates that titanium is a metal with a strong tendency to passivation. The titanium oxide film always maintains this characteristic when the medium temperature is below 315℃.
In order to improve the corrosion resistance of titanium, surface treatment technologies such as oxidation, electroplating, plasma spraying, ion nitriding, ion implantation, and laser treatment have been developed to enhance the protection of the titanium oxide film and obtain the desired corrosion resistance. effect.
In response to the need for metal materials in the production of sulfuric acid, hydrochloric acid, methylamine solution, high-temperature wet chlorine and high-temperature chloride, a series of corrosion-resistant titanium alloys such as titanium-molybdenum, titanium-palladium, titanium-molybdenum-nickel, etc. have been developed.
Titanium castings use titanium-32 molybdenum alloy, titanium-0.3 molybdenum-0.8 nickel alloy is used in environments where crevice corrosion or pitting corrosion is common, or titanium-0.2 palladium alloy is used locally in titanium equipment, and they are all well used. effect.
Good heat resistance
The new titanium alloy can be used for a long time at a temperature of 600°C or higher.
Good low temperature resistance
Low temperature titanium alloy represented by titanium alloy TA7 (Ti-5Al-2.5Sn), TC4 (Ti-6Al-4V) and Ti-2.5Zr-1.5Mo, etc., whose strength increases with decreasing temperature, but does not change plasticity. Big.
It maintains good ductility and toughness at low temperatures of -196-253°C, avoids cold brittleness of metals, and is an ideal material for cryogenic containers, storage boxes and other equipment.
Strong resistance to damping
After being subjected to mechanical and electrical vibrations, titanium has the longest vibration decay time compared with steel and copper.
This performance of titanium can be used as a tuning fork, medical ultrasonic pulverizer vibrating element and high-end acoustic speaker vibrating film.
Titanium is a non-magnetic metal and will not be magnetized in a large magnetic field. It is non-toxic and has good compatibility with human tissues and blood, so it is used by the medical profession.
The tensile strength is close to its yield strength
This property of titanium shows that its yield ratio (tensile strength/yield strength) is high, which means that the plastic deformation of metallic titanium material is poor during forming.
Due to the large ratio of the yield limit of titanium to the modulus of elasticity, the resilience of titanium during molding is large.
Good heat transfer performance
Although the thermal conductivity of metallic titanium is lower than that of carbon steel and copper, due to the excellent corrosion resistance of titanium, the wall thickness can be greatly reduced, and the heat exchange method between the surface and the steam is dropwise condensation, which reduces the heat group.
Without scaling, the thermal resistance can be reduced, and the heat transfer performance of titanium can be significantly improved.
Low modulus of elasticity
The elastic modulus of titanium is 106.4GPa at room temperature, which is 57% of steel.
Titanium is a chemically very active metal, which can react with many elements and compounds at high temperatures. Titanium getter mainly refers to the reaction with carbon, hydrogen, nitrogen, and oxygen at high temperatures.
Titanium tube applications
In today’s society where the water environment is tight, we are gradually realizing that seawater desalination can reduce water use. So what is seawater desalination equipment? Seawater desalination equipment refers to equipment specially used for desalinating seawater. Seawater desalination mainly uses two methods to desalinate seawater, namely, the distillation method and the reverse osmosis method to desalinate seawater.
Titanium pipes in seawater desalination equipment will gradually replace the original copper alloy pipes. Compared with the two, titanium pipes have the following advantages:
1. Under the same operating conditions, the wall thickness of the titanium tube is thinner and the amount of pipe material is less. Generally, the wall thickness of copper alloy pipes is 0.9mm-1. 2mm; instead of titanium pipes, thin-walled pipes with a wall thickness of 0.5mm can be used in places with low corrosiveness.
2. Titanium tube has good thermal conductivity. The thermal conductivity of titanium is 17W/(m·k), the thermal conductivity of aluminum brass is 100W/(m·k), and the thermal conductivity of 70/30 cupronickel is 29W/(m·k). The thermal conductivity of titanium is the smallest. But using thin-walled titanium tube, although the thermal conductivity is worse than aluminum brass, it is equivalent to 90/10 cupronickel and better than 70/30 cupronickel.
3. The use of titanium tubes is more cost-effective. The price of titanium tubes can compete with copper alloy tubes. Due to the low density of titanium and the same wall thickness, the quality of titanium tubes of the same length is only 50% of copper alloy tubes. When the wall thickness of titanium tubes is 50% of copper alloy tubes, the same transmission The quality of the titanium tube in the hot area is only 1/4 of that of the copper alloy tube. It can be seen that the titanium tube is competitive in terms of price.
4. Titanium tube has longer service life. Since seawater is often mixed with silt and marine organisms, they adhere to the heat transfer tube and the end of the tube, which will corrode the copper alloy tube, and the copper alloy will also be corroded by Br- in the seawater. However, in use, the hydrogen introduced from the external environment is called external hydrogen. Specifically, active hydrogen atoms are generated on the metal surface through the following ways, and then enter the metal:
(1) The medium where the titanium equipment is located contains molecular hydrogen, such as a high-temperature hydrogen atmosphere.
(2) Hydrogen generated by general corrosion or partial corrosion of titanium is absorbed by titanium. For example, Chin’s crevice corrosion is often accompanied by hydrogen absorption.
(3) Hydrogen generated when titanium and negatively charged metals undergo galvanic corrosion or cathodic protection is overprotected.