For cutting, general cutting methods can be used due to the high chemical activity and special physical and mechanical properties of titanium and titanium alloys. But compared with other commonly used metals, there are special requirements, master certain processing technology, and pay attention to it during the processing.
Design and manufacture of titanium valves should pay attention to
Is an economical and reasonable use of titanium, which is more expensive. For parts not in contact with corrosive media, titanium parts should be avoided as much as possible.
Design and manufacture of titanium valves should pay attention to
Is larger than ordinary carbon steel and alloy steel. The strength index decreases with increasing temperature, and the mechanical properties of titanium change with temperature. For example, the tensile strength and yield strength at 250300 ℃ are half of that at normal temperature. Even if the design temperature is not high, so. It should also be selected according to the intensity value at the design temperature. Titanium has a high yield strength ratio and good durability. When the design temperature is below 316 ℃, the tensile strength value at that temperature is often determined by the design strength index. For industrial pure titanium, the strength index value cannot be improved by heat treatment. When titanium is used in combination with other materials, the thermal expansion coefficient of titanium is small. Pay attention to the stress caused by the expansion difference.
Design and manufacture of titanium valves should pay attention to
Is prone to cracking. Increasing the deformation speed and reducing the deformation temperature may cause cracking during processing. Therefore, the plastic deformation range of industrial pure titanium and α-titanium alloy during press working is small. It is best not to design cold-worked parts with a large amount of deformation; where the flanging is required, the bending radius should be as large as possible; the gap tolerance between the tube connected with the strength expansion and the tube sheet tube hole should be small, so as not to swell the titanium tube.
Design and manufacture of titanium valves should pay attention to
It is necessary to consider the problem of stress relaxation due to the creep phenomenon of titanium at normal temperature. When using titanium bolts. It is best not to use titanium bolts as a force-sealing connector. When titanium bolts are required for corrosion resistance, the structural design needs to consider that it is easy to tighten the bolts regularly to ensure sealing. Titanium, like stainless steel, also has frictional bonding and biting. Titanium threads are easy to bite, and can be solved with different materials or larger clearance threads or with appropriate lubricants. Internal threads that require tapping should be used sparingly, and as far as possible, turn-thread structures with retreating slots should be used.
Design and manufacture of titanium valves should pay attention to
The adjustment and operation performance of the titanium valve is controlled by the stem thread, the same. The rotation of the hand wheel should be guaranteed by the performance of the data and the manufacturability of each part. In order to avoid crevice corrosion of titanium in certain media. When designing the structure, it is necessary to eliminate gaps and recesses that can hold water to the greatest extent.
Design and manufacture of titanium valves should pay attention to
Is also more susceptible to corrosion than the gap between titanium and titanium, especially the gap formed by titanium and tetrafluoride. Because titanium is not corrosion-resistant fluoride for solutions containing a small amount of soluble fluoride, the passive state is destroyed. Therefore, special care should be taken when using Teflon plastic pads, fluorine-containing rubber gaskets and adhesives.