Uporaba ventila iz titanove zlitine in izbira materiala

This article summarizes the commonly used titanium and titanium alloys, focuses on the application status of titanium alloy valves at home and abroad and the selection of components, analyzes some problems that should be paid attention to in the application of titanium valves, and points out the main application areas and development prospects of titanium valves in China in the future.

The density of titanium and titanium alloy is about 4.51g/cm, the tensile strength Rm>300Mβa, and the yield ratio can reach 0.9. Its light weight, high strength, high yield ratio, non-magnetic, biologically inert, and especially excellent resistance corrosion performance. It is both a modern metal and an important strategic metal. Its application in the national economy reflects a country’s comprehensive strength, economic strength, and national defense strength. It is an indispensable key material for high technology. Therefore, with the advancement of science and technology and the increasing application of new materials in various industries, titanium valves have been widely used as essential products for various special environments and special fluid medium delivery systems. However, the fluid media and environmental conditions in different fields and industries are different, and the performance requirements of the materials used in the titanium valve are different; at the same time, due to the difference in the performance requirements of different components of the titanium valve, the molding process is different, and some parts are required to reduce costs. Due to factors such as the selection of substitute materials, the selection of materials has become one of the first technical issues that must be considered in the design and manufacture of titanium valves, and has received a lot of attention and attention. Based on the application research results of titanium and titanium alloy materials, this article reviews the properties of commonly used titanium and titanium alloys and the influence of different elements on the properties of titanium materials.

The performances of commonly used titanium and titanium alloys, etc., combined with the current application status and prospects of titanium valves at home and abroad, introduce the current application status of titanium alloy valves at home and abroad, common selection of titanov ventil components, and hope to contribute to the development and growth of China’s titanium valve industry. The wide application of this new product of titanium valve helps.

Summary of commonly used titanium and titanium alloys

What is industrial pure titanium?

Industrial pure titanium refers to several kinds of unalloyed titanium with different impurities such as Fe, C, N, and 0. It cannot be strengthened by heat treatment, has excellent forming properties, and is easy to weld and braze. Industrial pure titanium has a wide range of practical applications. Typical deformed industrial pure titanium grades are TA1, TA2, TA3, etc.; typical casting industrial pure titanium grades are ZTA1, ZTA2, ZTA3.

What is titanium alloy?

Titanium alloy refers to an alloy composed of Al, sn, Cr, Mo, Mn, etc., based on titanium. Titanium alloys are usually classified according to the annealed phase composition, and are divided into α-type, α+β-type, and β-type titanium alloys.
The main component of α-type titanium alloy is an alloy in which Al, Sn, Cr and other α-stabilizing elements are added to Ti, and the structure in the retracted state is a single-phase α solid solution. α-type titanium alloy cannot be strengthened by heat treatment, and its strength is lower than the other two types of titanium alloys, but it can maintain good high temperature strength when used at 500-600%. The main advantages of this type of alloy are good welding performance, casting performance, pressure processing performance, structural stability and no cold embrittlement. The disadvantage is lower process plasticity and sensitivity to hydrogen embrittlement. The practical application of α-type titanium alloy is very extensive. Typical α-type deformed titanium alloy grades are TA5, TA7, TA9, etc.
The main components of β-type titanium alloys are alloys with elements such as Cr, No, and V. After quenching, these alloys obtain β solid solution structure, which has high strength and impact toughness, as well as good pressure processing performance and welding performance. The disadvantage is that the organization and performance are not stable, the smelting process is complicated, and the application is less. Stable β-type titanium alloys are Ti7 and Ti40.
The room temperature structure of the αα+β titanium alloy is αα+β. It is an αα+β titanium alloy containing 5%-25% β phase in a stable state and a martensite phase formed by rapid cooling from the β zone. It can It is strengthened by heat treatment, quenching and aging treatment. The α+β titanium alloy has a wide range of mechanical properties, and has better comprehensive properties in a wide temperature range, and can be suitable for various purposes. Typical α+β type deformed titanium alloy grades are TC4, TC16, TC11, etc.; typical αα+β type cast titanium alloy grades are ZTC3, ZTC4, and ZTC5.

The influence of different elements on the properties of titanium

Understanding the effects of different elements on the performance of titanium materials is very important for the processing, manufacturing, inspection and acceptance of titanium valve products, and ensuring product quality. 0, C and N are impurities often present in titanium. The impurity content has a great influence on the mechanical properties of titanium. They can increase the strength of titanium and reduce its plasticity. N has the greatest influence, C has the least influence, and O is in the middle.
In addition to 0, C, and N, the elements that have a greater impact on increasing the strength of titanium are β, βe and Al. Other elements have less strong influence on the strength of titanium, and can be arranged in order according to the degree of influence: Cr, Mo, Mn, Fe, V, sn. Al is often used as a stable element and an important alloying element in α-type and α+β-type titanium alloys. It refines the grains of the alloy, increases the recrystallization temperature and phase transition temperature, and has a significant strengthening effect. It can also reduce the density of the alloy. Increase the modulus of elasticity of the alloy. Mo is often used as a β-stabilizing element and an important alloy element in β-type and α+β-type titanium alloys. It is designed to have a greater strengthening effect without significantly reducing the plasticity of the material, and can simultaneously improve the fracture toughness and resistance of the material. Corrosion, reduce its stress corrosion sensitivity. In addition, H also has a greater impact on the mechanical properties of titanium and titanium alloys, and its impact is mainly reflected in hydrogen embrittlement. After the H content reaches a certain value, it will greatly increase the sensitivity of titanium and titanium alloys to notches, thereby reducing notched samples The impact toughness and other properties. It is generally believed that the hydrogen content should be less than 0.007% to 0.008% (mass fraction), and it is not allowed to exceed 0.0125% to 0.015% (mass fraction). Above this content, hydrides will be precipitated on the tissue and obvious hydrogen will appear. Brittle phenomenon. For titanium and titanium alloys, hydrogen embrittlement is an important issue. Titanium easily absorbs hydrogen from pickling liquids, etching liquids, and high temperature atmospheres of thermal processing. Hydrogen embrittlement of titanium and its alloys often has two manifestations. One is a slight increase in strength and a decrease in plasticity and impact toughness; the other is embrittlement similar to steel, which is carried out at a slow speed under constant load or continuous load. An embrittlement phenomenon that occurs during stretching.

Typical titanium materials for castings and their mechanical properties

Casting technology is often used to produce complex shapes and multi-curved workpieces (such as the valve body and valve cover of titanium valves). Therefore, in order to be cast, the metal used for casting must first have good fluidity and manufacturability. The mechanical properties of typical cast titanium and titanium alloys at home and abroad are shown in Table 1.
Table.1 Mechanical properties of typical cast titanium and titanium alloys at home and abroad

Technical standard		Razred		Status	Rm (MPa)	Ro.2 (MPa)	A (%)	HBS
Kitajska	Združene države Amerike	Kitajska	Združene države Amerike
GB/T 6614	ASTM B367 ASTM B367 ASTM B367	ZTA1 ZTA2 ZTA3	C2 C3 C4	Annealing	≥345 ≥440 ≥540	275 370 470	20 12 13	≤210 ≤235 ≤245

Typical titanium materials for forgings and their mechanical properties

Forgings must be formed using deformable materials with good plasticity. The mechanical properties of typical forged titanium and titanium alloys at home and abroad are shown in Table 2.

Technical standard		Razred		Status	Rm (MPa)	Ro.2 (MPa)	A (%)	Z (%)	αku (kJ/m2)
Kitajska	Združene države Amerike	Kitajska	Združene države Amerike
GB/T 2965	ASTM B381 ASTM B381 ASTM B381	TA1 TA2 TA5 TA4	F2 F3 F5	Annealing	≥240 ≥400  ≥685   ≥895	140 275 585 825	24 20 15 12	30 30 40 25	490 490 800 350

Note: αku value is a reference value for quoting other materials, not from the GB/T2965-2007 standard.

Titanium valve application and its materials

Application and materials of titanium valve in the aerospace field

The high strength and low density of titanium and titanium alloys provide a large space for its wide application in the aerospace field. Titanium alloy and its valve products are widely used in the aerospace field. Only in terms of the types of valves used, they mainly involve regulating valves, needle valves, etc., and more are mainly small specifications and non-standard design valves. The application of titanium alloy and its valve products in the aviation field is not only wide, but also huge. An ultra-large passenger aircraft-Airbus A380, uses 45-65T of titanium per aircraft; the US subsonic Boeing passenger aircraft uses 15% to 17% of its total weight, and the F18 carrier-based fighter uses titanium to account for its total weight. The most advanced fourth-generation fighter F-22 uses 4l% of its total weight. Titanium alloy valves are widely used in various pipelines on the aircraft. The types of valves involve regulating valves, stop valves, check valves, needle valves, plug valves, ball valves, butterfly valves, etc. The titanium used for valves includes pure titanium ( Such as ASTM B367C2) and titanium alloy Ti-6AI-4V (ASTMB381F5), Ti-6AI-6V-2Sn, Ti-6A1-2Sn-4Zr-2Mo, Ti-6A1-2Sn-4Zr-6Mo, etc., but pure titanium and titanium alloy Ti-6A1-4V is more common. The fastener material of titanium valve used in aviation field is Ti-6AI-4V in the United States and BT16 in Russia.

Application of titanium valve in the chemical industry and its materials

In 2010, the sales volume of major domestic titanium processing material companies in the chemical industry reached 19,718 tons, accounting for 53.2% of the total sales volume. From this data, it is not difficult to see that titanium has a very wide range of uses in the chemical industry. As a key system component of fluid transportation control in titanium alloy pipelines, titanium valves are essential for their use. Therefore, the amount of titanium valves in the chemical industry is not mentioned. Yu. In chlor-alkali projects, salt industry, synthetic ammonia projects, ethylene projects, nitric acid projects, acetic acid projects and other projects that involve strong corrosive media and environments, ordinary metals such as carbon steel and stainless steel cannot meet the requirements due to poor corrosion resistance and must be used For the special titanium alloy with excellent corrosion resistance, a large number of titanium valves must be used in the control and adjustment parts of the medium conveying pipeline. Large-scale purified terephthalic acid project can be used as a typical application of titanium valve, because its medium mainly involves high temperature and high concentration acetic acid containing certain impurities, and the environment is special and the medium must be high corrosion resistant materials. Therefore, titanium valves of different types and specifications are widely used. The types of valves used involve gate valves, globe valves, check valves, safety valves, ball valves, butterfly valves, and so on. Titanium valves used in domestic large-scale purified terephthalic acid projects rely heavily on imports for a long time, and most of the valve bodies use ASTM B367 C2 (castings) or ASTM B381 F2 (forgings); valve internals mostly use ASTM B381 F5. Valve fasteners, as important parts of valves, are also very important in valve design and manufacturing. As far as the selection of fasteners for valves is concerned, there are generally two types in foreign countries. ASTM B381 F5 is generally used for the parts in contact with the medium, and for the fasteners that are not in direct contact with the medium outside the valve, substitute materials with a certain surface treatment are often used. Such as stainless steel ASTM A194-8M, etc., can reduce costs, and purchase is relatively easy. Domestic breakthroughs have been made in the design and manufacturing of large-size forged titanium valves. The large-size (~DNS00) forged ball valves, butterfly valves, and check valves designed and manufactured by China Shipbuilding Industry Corporation No.725 have broken the foreign monopoly. For the first time, it realized batch supply and successful application in a large-scale purified terephthalic acid project. Titanium valves are widely used in the chemical industry, but it must be noted that they are not suitable for any chemical medium. Among them, 4 kinds of inorganic acids: hydrofluoric acid, hydrochloric acid, sulfuric acid and orthophosphoric acid, and 4 kinds of hot concentrated organic acids: oxalic acid, formic acid, trichloroacetic acid, trifluoroacetic acid and extremely corrosive aluminum chloride. There is a serious corrosive effect, so the titanium valve is not suitable for this kind of chemical medium, and attention should be paid to it in use.

Application of titanium valve in the field of ships and its materials

Russia’s development of titanium alloys for ships began in the 1960s, and it is internationally recognized as one of the countries with the earliest, deepest research and most widely used titanium alloys for ships. In terms of the development level of the titanium industry and the scale of use of titanium alloys in the shipbuilding industry, Russia is far ahead of all other countries in the world. From the 1960s to the 1980s, Russia produced a series of attack submarines, including the “Alpha” class submarine with a titanium alloy consumption of 3000t and the “Typhoon” class submarine with a titanium consumption of 9000t. The types of titanium alloy valves in the marine seawater piping system involve side valves, stop valves, check valves, etc., and they are widely used and mature. Titanium alloy valves used in Russian ships mostly use 3M alloy and TB3 alloy.
Tyco Flow Control Company (Tyco-flowcontro1), CLA.VAL Company, Cunico Company, etc. cooperate with the US Navy to provide valves and control solutions for its ships and submarines. The titanium alloy valve products it produces are not only highly versatile, And it is small in size and excellent in performance. It is used in sea water systems such as aircraft carriers, nuclear submarines, destroyers, amphibious dock helicopter ships, etc. The most representative ships such as the United States’ LPD.17 have used a large number of titanium alloy pipelines and titanium alloy valves in their seawater systems. The body materials of American titanium alloy valves are mostly ASTM B367 C2, and the materials of internal parts are mostly ASTM B381 F5 En.

Application of titanium valve in nuclear power field and its materials

Titanium and titanium alloy valves are widely used in power stations, especially in the field of nuclear power. The rational and safe use of nuclear energy is a major advancement for mankind and a major direction in the development and utilization of new energy. At present, many developed countries in the world have nuclear power plants. According to statistics, there are currently 447 nuclear power plants in operation in the world, with a total installed capacity of 380 million kilowatts, accounting for approximately 16.2% of the global power generation. The installed nuclear power capacity of 17 countries accounted for more than 25% of their total power generation, of which France accounted for 7%, South Korea 38%, Japan 36%, Britain 28%, and the United States 20%. Due to the potential for nuclear pollution in nuclear power plants, power plants are built along the coast. Many facilities in nuclear power plants involve seawater as a special medium. Titanium has the reputation of “marine metal”. Its excellent seawater corrosion resistance makes the amount of titanium products in the nuclear power field very large. , Titanium valve is one of them. In addition, titanium valves are also widely used in ordinary power stations. As far as power station valves are concerned, the construction of power stations in China is developing towards large-scale, so large-diameter and high-pressure safety valves, pressure reducing valves, globe valves, gate valves, butterfly valves, emergency shut-off valves, flow control valves, and spherical seals are needed. Instrument shut-off valve and so on. As China’s nuclear power plant construction shifts from experimental and compensatory to strategic and aggressive development, it has brought broad market prospects for nuclear power valves. Nuclear power valves are a large number of medium transmission control equipment used in nuclear power plants. They are an essential part of the safe operation of nuclear power plants. The proportion of investment in nuclear power plants accounts for about 1.6% of the total cost of nuclear power plants. In terms of valve configuration, globe valves accounted for 33.6%, diaphragm valves accounted for 26.2%, and ball valves accounted for 12.8%. Titanium valves occupies a considerable proportion of such a huge amount of valves, and titanium valves are mainly made of titanium materials that have been verified by anti-radiation tests. In the field of nuclear power valve processing and manufacturing, 19 domestic enterprises have obtained the civil nuclear pressure equipment design and production qualification license issued by the National Nuclear Safety Administration. The types of nuclear valves that can be designed and produced include gate valves, globe valves, and regulating valves Wait. Among them, there are 5 companies capable of designing and producing nuclear Class I valves (China Nuclear Su Valve, Shenyang Shengshi, Dalian Dago, Shanghai Valve, Shanghai Lianggong).

Application of titanium valve in other fields and its materials

Titanium and titanium alloy valves are widely used in offshore platforms, paper industry, food and medicine and other fields. The environment of offshore drilling platforms mainly involves media such as seawater, and titanium valves have become a must product and are widely used. In recent years, offshore oilfield exploitation has entered a period of rapid development. The demand for titanium alloy valves for offshore platforms has increased year by year, mainly related to ball-break valves, check valves, multi-way valves, etc. The valve materials mostly use pure titanium.
The papermaking industry is one of China’s traditional industries. The environmental pollution of the papermaking industry is relatively serious, involving strong alkaline media, which has extremely strong corrosion properties. The cevi, pumps, valves, fans, agitators, etc. in the paper industry are often made of titanium alloys, and titanium alloys are widely used. As far as pipeline valves are concerned, pure titanium ball valves, globe valves, etc. are more widely used.
Food and pharmaceutical manufacturing are directly related to human health. As we all know, a major feature of titanium and titanium alloys is their biological inertness, that is, no toxic effects on the human body or other organisms. Therefore, titanium and titanium alloys are widely used in food processing and pharmaceutical fields. High-end food processing companies and pharmaceutical factories are Applied to titanium equipment, pipelines and valves. Titanium valves used in this field mainly include pure titanium ball valves and butterfly valves.

Prospects for the application of titanium valves

After 20 years, especially in recent years, the joint efforts of combining scientific research, design, manufacturing and users, China’s valve industry has achieved rapid development. In 2008, the State Council issued the “Several Opinions on Accelerating the Revitalization of the Equipment Manufacturing Industry”, which led to the overall revitalization of the equipment manufacturing industry. For this reason, the National Development and Reform Commission, China Machinery Industry Federation, China Communications Association and other relevant departments have proposed a plan to gradually realize the localization of major equipment valves during the “Eleventh Five-Year Plan” period, including the realization of key valves for million-kilowatt nuclear power plants and million-ton tons Domestic production of valves for large-scale ethylene equipment. Through continuous introduction of key technologies and independent research and development, and granting many preferential regulations and policies, relevant valve companies seized the opportunity and reached a consensus, and the valve industry has made gratifying progress. The valve industry has always maintained a good development trend. From January to May 2010, the cumulative product sales revenue was 55.7 billion yuan, an increase of 24.7% over the same period last year; the cumulative profit was 3.7 billion yuan, an increase of 35.33% over the same period last year. In 2010, sales revenue increased by more than 21% compared with the previous year; in 2011, sales revenue increased by more than 19% compared with the previous year. According to statistics and forecasts, by 2020, China’s valve market will surpass the United States to become the world’s largest, with an average annual growth rate of about 11% from 2010 to 2015. In the entire high-end valve market, medium and high-end valves account for about 30%, of which titanium alloy valves account for a certain proportion. With the rapid development of China’s national economy, from 2015 to 2020, the petrochemical, PTA, and LNG valve market with a large application of titanium valves is expected to grow by 13% annually, from 1.2 billion US dollars in 2010 to approximately 4.88 billion in 2020 US dollars; the power industry will maintain an annual growth rate of 6%, from US$2 billion in 2010 to about US$5 billion in 2020. Therefore, the application prospect of titanium valve in this field is very promising.
In recent years, China’s aerospace industry has developed rapidly, and the building of large aircraft, the construction of the moon and space station has become a major national policy. Therefore, in view of the excellent characteristics of titanium alloys and the successful application experience of titanium valves in developed countries in this field, the application of titanium valves in this field will increase substantially. In addition, with the continuous enhancement of China’s economic strength, the strengthening of naval construction and the development and utilization of marine resources, the demand for titanium valves in the field of ship construction and offshore drilling platforms will greatly increase in the future. Whoever owns the energy has the future. Offshore oil exploration is the focus of China’s future oilfield exploration. Titanium alloy valves will have a very broad application prospects in offshore drilling platforms.
Food hygiene and medical care are increasingly being valued by the Chinese and relevant national departments. Titanium alloy is the best metal used in food processing and pharmaceutical manufacturing. China has a population of 1.3 billion, accounting for 1/6 of the world’s total population. Therefore, The future market and application prospects of titanium valves in this field will also be very broad.

Zaključek

As a kind of fluid control necessities in special media and environments, titanium valves have been processed, manufactured and applied for many years in developed countries abroad. The application fields of their valves and the types of materials and grades used are important for China’s design and processing of high-end valves. Great help. With the rapid development of China’s national economy, China will become the country’s largest valve market in the future, and the application prospects of titanium valves are very broad. Researching and mastering the application status of domestic and foreign titanium valves and the law of design and selection are beneficial to the rapid growth and healthy development of China’s titanium valve industry.

Vir: China Titanium Valve Provider: www.titaniuminfogroup.com