How to choose the valve electric actuator valve new product development technology ideas

How to choose the valve electric actuator valve new product development technology ideas

First, select the electric actuator according to the valve type
1. Angular stroke electric actuator (Angle 360 degrees) is suitable for butterfly valve, ball valve, plug valve, etc.
The rotation of the output shaft of the electric actuator is less than one week, that is, less than 360 degrees, usually 90 degrees to realize the control of the valve opening and closing process. This kind of electric actuator can be divided into direct connection type and base crank type according to the different installation interface mode.
A) Direct connection: it refers to the form of direct connection between the output shaft of the electric actuator and the valve stem.
B) Base crank type: refers to the form of the output shaft connected with the valve stem through the crank.
2. Multi-turn electric actuator (rotation Angle 360 degrees) is suitable for gate valve, globe valve, etc.
The rotation of the output shaft of the electric actuator is greater than one week, that is, greater than 360 degrees. Generally, more than one turn is needed to realize the control of the valve opening and closing process.
3. Straight stroke (straight motion) is suitable for single seat regulating valve, double seat regulating valve, etc.
The movement of the output shaft of the electric actuator is linear, not rotational.
2. Determine the control mode of the electric actuator according to the production process control requirements
1. Switch type (open-loop control)
Switching type electric actuators generally realize the opening or closing control of the valve. The valve is either in the fully open position or in the fully closed position. This kind of valve does not need to control the medium flow. It is especially worth mentioning that switching electric actuators can be divided into separate structure and integrated structure due to different structural forms. This must be explained when selecting the type, otherwise it often occurs in the field installation and control system *** and other mismatches.
A) Split structure (usually called common type) : the control unit is separated from the electric actuator. The electric actuator cannot control the valve alone. An external control unit is required to realize the control. The disadvantage of this structure is not easy to install the whole system, increase wiring and installation costs, and prone to failure, when the fault occurs is not easy to diagnose and maintenance, cost-effective is not ideal.
B) Integrated structure (usually called integral type) : the control unit and the electric actuator are packaged into one, which can be operated in situ without external control unit, and can be operated remotely only by output of relevant control information. The advantages of this structure are easy to install the whole system, reduce wiring and installation costs, easy to diagnose and troubleshoot. But the traditional integrated structure products also have many imperfections, so the intelligent electric actuator is produced.
2. Regulating type (closed-loop control)
The regulating electric actuator does not have the function of switch type integrated structure, but also can control the valve and adjust the medium flow.
A) Type of control signal (current and voltage). The control signal of the regulating electric actuator generally includes current signal (4 ~ 20mA, 0 ~ 10mA) or voltage signal (0 ~ 5V, 1 ~ 5V). The type and parameters of the control signal should be specified when selecting the type.
B) The working form (electric open type and electric close type), the working mode of the regulating electric actuator is generally electric open type (take 4 ~ 20mA control as an example, electric open type refers to the 4mA signal corresponding to the valve close, 20mA corresponding to the valve open), and the other type is electric close type (take 4-20MA control as an example, electric open type refers to the 4mA signal corresponding to the valve open, 20mA corresponds to the valve close).
C) Loss of signal protection. Loss of signal protection refers to that when control signals are lost due to line faults, the electric actuator will open and close the control valve to the set protection value. The common protection value is fully open, fully closed and in situ.
Three, according to the use of environment and explosion-proof grade classification of electric devices
According to the use of environment and explosion-proof grade requirements, the valve electric device can be divided into ordinary type, outdoor type, flameproof type, outdoor flameproof type, etc.
4. Determine the output torque of the electric actuator according to the torque required by the valve
Valve opening and closing the required torque determines the output torque of electric actuator to choose how, generally is put forward by the user or by matching valve manufacturer, as the actuator manufacturer is only responsible for the output torque of actuators, normal valve opening and closing the required torque is determined by the valve diameter size and working pressure, but because of the valve manufacturer processing precision, the assembly process, Therefore, the torque required by valves of the same specification produced by different manufacturers is also different, even the torque of valves of the same specification produced by the same valve manufacturer is also different. When the type is selected, the torque selection of the actuator is too small, it will not be able to open and close the valve normally, so the electric actuator must choose a reasonable torque range.
Five, the basis for the correct selection of valve electric device:
Operating TORQUE: THE OPERATING TORQUE IS THE MAIN PARAMETER TO SELECT THE VALVE ELECTRIC device. The output torque of the electric device should be 1.2 ~ 1.5 times of the valve operating torque.
Operating thrust: there are two kinds of main engine structure of valve electric device: one is not configured with thrust disc, direct output torque; The other is to configure a thrust disc, and the output torque is converted to the output thrust through the valve stem nut of the thrust disc.
The number of rotation turns of the output shaft of the valve electric device: the number of rotation turns of the output shaft of the valve is related to the nominal diameter of the valve, the stem pitch and the number of thread heads, which should be calculated according to M=H/ZS (M is the total number of rotation turns that the electric device should meet, H is the opening height of the valve, S is the screw pitch of the stem drive, and Z is the number of thread heads of the valve stem).
Stem DIAMETER: FOR MULTI-TURN OPEN STEM VALVES, AN ELECTRIC VALVE CANNOT be ASSEMBLED IF THE LARGE STEM DIAMETER ALLOWED BY THE ELECTRIC DEVICE does not pass through the stem of the supplied valve. Therefore, the inner diameter of the hollow output shaft of the electric device must be greater than the outer diameter of the stem of the open-rod valve. For part of the rotary valve and multi-rotary valve in the dark rod valve, although do not consider the diameter of the valve stem through the problem, but in the matching should also fully consider the diameter of the valve stem and the size of the keyway, so that the assembly can work normally.
Output speed: If the opening and closing speed of the valve is too fast, it is easy to produce water hammer phenomenon. Therefore, the appropriate opening and closing speed should be selected according to different conditions of use.
Valve new product development technology ideas
Valve is used in all fields of the national economy and people’s livelihood, because to adapt to the requirements of different working conditions, so it has a large number of varieties. Our country’s valve manufacturing industry is very large, valve manufacturers are thousands of, all over the country. Our country has become one of the global valve output and market demand countries which are large. But most of China’s valve industry for small and medium-sized enterprises, the good and bad are intermingled, annual output value over one hundred million yuan  three, even compared to other domestic machinery industry, both on the equipment and technology level and there is a big gap, really has the  products research and development capacity of the unit are very few, therefore in the large petrochemical, nuclear power, oil and gas long distance pipeline and other major projects, Supporting valves are mainly imported at present.
At present, valve enterprises attach great importance to the development of new products. It should be noted that the valve industry in our country develops to , although the gap with the international advanced level still exists, but it has gone beyond the stage of simply copying and absorbing. To seek the technical way of further development, we should analyze and reflect on the trend of valve technology development and product development from a deeper level, and strive to develop new products with independent intellectual property rights.
First, people-oriented, establish the concept of humanized product design
Usually we are mainly considered in the product design is its material, structure, mechanical strength, performance, service life and other factors, in the evaluation of the merits of the valve, in general is also the use of these indicators. With the development of The Times and the progress of society, the idea of people-oriented has penetrated into all fields of social life. We can clearly feel this change from housing, cars, computers, mobile phones, clothing and various public facilities. They from safety, comfort, energy saving, environmental protection, novel, beautiful and many other aspects in every detail to consider the consumer’s feelings, reflecting the care for people. Obviously, humanized design should not be confined to the category of consumer goods, valves, as a kind of enormous quantity wide, applied in industry, agriculture, * * * * * and is closely related to People’s Daily work life of mechanical products, also can’t always constrained by traditional design concept and design method, and should explore new ideas and inject new ideas.
When we analyze foreign advanced products, in addition to the technical performance indicators, we will notice its beautiful shape, delicate structure, clean cavity, exquisite details. For example, in order to prevent secondary contamination, even the drain valve does not use asbestos-containing sealing packing and gaskets. Also, in order to avoid the operator’s hand being scratched, the connecting bolt end of the flange is processed into a curved surface and so on. The differences in these specific details should trigger our deeper thinking: why does it want to do so? How could it even think of doing that? Conclusion have to boil down to the humanized design concept, went up from the level of understanding, will make our product design is no longer stay in the first stage, the simple but from the perspective of man-machine engineering, from a more safe, reliable, energy saving, environmental protection, clean production, operation comfort and convenience, easy disassembling maintenance to delve into many aspects, such as thinking, Endows the valve this traditional product with the brand-new concept and the image, forms the own characteristic.
2. Pay attention to the progress of material science, and apply new materials, new technologies and new processes to valve products in a timely manner
With the progress of technology, industrial production in high temperature and high pressure, low temperature, high vacuum, corrosive, radioactive, toxic, flammable and explosive increasing contour parameters of the complex working conditions, thus the valve using the function of security, reliability and service life, etc, put forward the higher and more stringent requirements, so development adapted to the working condition of high parameter of all kinds of valves, Naturally, it has become a common concern of valve manufacturing industry, engineering design department and users, and the main technical obstacles to solve the problem are often material.
Material science is regarded as one of the promising disciplines in the new century. In recent years, many new high-performance materials have appeared, such as various nanomaterials, superconducting materials, functional materials, organic synthetic and polymer materials, inorganic nonmetallic materials and various composite materials. At the same time many casting, welding, spray welding, spraying, composite, sintering and other forming and surface treatment of new technology and new technology equipment. Paying close attention to the information, trends and achievements of material engineering research and development, and applying them to valve products in time is an important technical way to develop high performance and high parameter valves. In particular, it is worth mentioning that industrial ceramics as the first inorganic non-metallic materials, used in temperature resistance, corrosion resistance and erosion resistance valve parts, often achieve good results.
3. Integrating information technology and artificial intelligence technology into valves and realizing integration is a new way of technological innovation
In the former era, the rapid development of information technology, information and intelligence is constantly changing the face of industrial and agricultural production and people’s social life. Valve as terminal actuators to control the fluid motion in the pipe, if able to modern computing technology, sensor technology, network and remote control technology and intelligent technology into the valve products, the valve will be endowed with new concept, is completely different from the original products are produced by new structure and working mechanism of the valve product upgrade. In recent years, the regulator, safety valve, pressure reducing valve, trap and other products have begun to show signs. Such as spring safety valve is the * * * * * used a relief valve, but as the production equipment of large-scale and high parameter, this type of relief valve on the structure size and reliability are difficult to meet the requirements of production, if the relief valve pressure sensor is installed inside control valve rapid opening and closing, the valve will be a kind of brand-new mode. And such as the current trap type of many, its working principle is to use steam and condensed water temperature, density, flow rate difference, through the complex mechanism to realize the valve opening and closing, complete the function of gas drainage. A new type of trap is to be able to identify gas-liquid components and valves formed into one, to control the opening and closing of the valve, according to this idea of the design of the new trap, has been reported abroad.
Four, expand the vision, establish the concept of large project, familiar with the process characteristics of large complete sets of equipment, develop high technology and high added value of the best valve products
As the supporting equipment in the industrial production device, the valve plays a very important role in ensuring the safe and normal operation of the process. The development of new valve products can not be separated from the closely related production equipment and production process. In the rapid development of science and technology, industrial production of new products, new technology, new processes, new devices continue to emerge, so that the matching valve in function, structure, material also put forward new requirements accordingly. It is an important theme for the development of new products to develop all kinds of customized valves for specific industries and specific technological processes, and it is also an urgent need for the localization of major technology and equipment, such as nuclear power valves, oil and gas long-distance pipeline valves, coal chemical slurry valves, etc. To this end, to have the concept of a large project, with a few design parameters, on the valve valve is not good, to have a complete concept of the whole project and complete sets of equipment, understand its production process, production environment, operating conditions and the relevant technical specifications, on this basis, Only in this way can we conceive, develop and design characteristic products to meet the needs of the project, just as writers can create good works only when they go deep into life.
The valve category is various, thousands of different, the market demand is constantly changing, the valve manufacturer’s production scale and the technical level is uneven, but the valve product in the general development trend and the development of the technical way has a lot in common. If the valve enterprises can combine their own conditions, and determine the development goal of their new product along the scientific and technical way, they will take fewer detours, promote the valve industry in our country to develop continuously and healthily.