What are the methods of cleaning titanium tubes?

Titanium tubes are light in weight, high in strength and superior in mechanical properties. Titanium tubes are widely used in heat exchange equipment, such as shell and tube heat exchangers, coil heat exchangers, serpentine tube heat exchangers, condensers, evaporators and pipelines. Many nuclear power industries use titanium tubes as standard tubes for their units. Huayu titanium tube manufacturer took us to see what are the methods of cleaning titanium heat exchanger tubing?

1. Alkaline cleaning: Soak the titanium tube with 3-5% sodium hydroxide analytically pure solution for 30-60 minutes at a temperature of about 40 degrees. Good in an ultrasonic cleaner. After immersion, flush the inside and outside with filtered deionized water or water for injection until neutral, and measure the conductivity. Blow dry with pure air ≥ 0.4Mpa pressure.

2. Pickling: Soak the Seamless Titanium Tube Grade 2 in 5% nitric acid solution for more than 8 hours at a temperature of 40 degrees. Good in an ultrasonic cleaner. After immersion, flush the inside and outside with filtered deionized water or water for injection until neutral, and measure the conductivity. Blow dry with pure air ≥ 0.4Mpa pressure.

3. The above two methods can be used alone or in conjunction with each other. If conditions permit, it can be combined with an ultrasonic cleaning machine for good results.

4. Organic matter pollution can be cleaned in combination with surfactants, and the debris pollution system combined with enzyme cleaning has a good effect.

Titanium alloy wear-resistant composite treatment technology

At present, driven by the growing industrial demand, composite coating technology will gradually replace single coating technology. Micro-arc oxidation is also called micro-plasma oxidation. This technology can prepare ceramic layers with good metallurgical properties on the surface of light metals Al, Mg, Ti and corresponding alloys with the help of high voltage, high current and instantaneous high temperature. The main component of the ceramic layer is the oxide grown in situ on the substrate, and the electrolyte components will also participate in the micro-arc oxidation film layer. The electrical parameters in the micro-arc oxidation process (such as solution formulation, voltage and current, duty cycle, pulse frequency, etc.) have a great influence on the preparation and microstructure of the micro-arc oxidation film. This method has the advantages of safe process, simple operation, and environment-friendly solution. It also has the advantages of simple process, uniform and dense film layer, and less restrictions on the size of workpieces, which cannot be compared with other treatment technologies.

ASTM F136 6Al-4V ELI Titanium Bar alloy micro-arc oxidation film has the advantages of high hardness, high bonding strength of film base, corrosion resistance and wear resistance, but the surface of the film layer is rough, loose and porous, and the friction coefficient is large, which reduces the wear resistance of the film layer. , which shortens the service life of the oxide film, which is not conducive to the application of titanium alloys in abrasive environments. At present, some research institutes of the Russian Academy of Sciences have carried out a lot of work to improve the defect of titanium alloy micro-arc oxidation film, but domestic attention to this issue has just started.

Medical basis of titanium alloy

The main advantages of using Titanium Grade 2 Round Bar and titanium alloys as human implants are: (1) Density (20°C) = 4.5g/cm3, light weight. Implanted into the human body: reduce the burden on the human body, as a medical device: reduce the operating load of medical personnel. (2) Low elastic modulus, pure medical titanium plate is 108500MPa, implanted in the human body: it is closer to the natural bone of the human body, which is beneficial to bone joint and reduces the stress shielding effect of bone on the implant. (3) Non-magnetic, not affected by electromagnetic fields and thunderstorms, which is beneficial to human safety after use. (4) Non-toxic, as an implant, it has no toxic and side effects on the human body. (5) Corrosion resistance (biologically inert metal material), which has excellent corrosion resistance in the immersion environment of human blood, ensures good compatibility with human blood and cell tissue, does not produce human pollution as an implant, and does not Allergic reactions will occur, which is the basic condition for the application of titanium and titanium alloys. (6) High strength and good toughness. Due to trauma, tumors and other factors that cause bone and joint damage, in order to establish a stable bone support, arc-shaped plates, screws, artificial bones and joints must be used. These implants should be left in place for a long time. In the human body, it will be subjected to bending, torsion, extrusion, muscle contraction and other effects of the human body, requiring implants to have high strength and toughness.

What are the common problems in the process of titanium alloy processing?

Titanium alloy has the characteristics of high strength, small specific gravity, corrosion resistance, low temperature resistance and high temperature resistance. According to the structure after annealing, it can be divided into α-phase titanium alloy, β-phase titanium alloy, and α-β-phase titanium alloy. The α-phase titanium rectangular bar alloy (TA type) cannot be strengthened by heat treatment, so the room temperature performance is not high, it has medium plasticity, and the machinability is acceptable. The β-phase Grade 3 Pure Titanium Sheet alloy can obtain higher room temperature performance through quenching and aging treatment. When α β phase titanium alloy (TC type) is processed, the contact length between the chip and the front is short, and the cutting force acts near the cutting edge. Due to the small thermal conductivity, the temperature of the cutting edge is high, which accelerates the wear of the drill bit, and due to work hardening The phenomenon is more serious, and the elastic coefficient is smaller, so the shrinkage of the drilled hole is larger, which also affects the life of the drill bit.