1. Increasing pressure
One of the biggest advantages of hydraulic technology is the large capacity ratio, the most important of which is the high pressure. The working pressure of 2.5-6.3MPa in the last century has risen to 35-42MPa and even 48MPa today. However, in most application areas, it is still between 21-35MPa. The working pressure of today's pump has reached 42MPa, and the peak pressure is 48MPa, which requires that the pressure of the valve must also be above 42-48MPa. The threaded cartridge valve and the two-way cartridge valve are the most able to withstand this pressure. It is also possible to experience higher levels of stress. At present, from the perspective of materials and applications, 35-42MPa is moving toward economic rationality.
2. The development of the increase and decrease of valve diameter
The increase of the valve diameter means that the flow rate of the valve is constantly increasing. The maximum diameter of the threaded cartridge valve is M48×2, and the throttle valve flow rate can reach 1600l/min. Logic valve flow up to 800l/min; Check valve flow 640l/min; Balance valve, flow valve, etc 200-480l/min. This is the largest diameter of any threaded cartridge valve available today. The other direction is that the valve can be reduced in a smaller direction for small flow ranges, such as less than 5l/min, which is already more difficult in other valve types.
There are generally three measures for the development of threaded cartridge valves to large flow rates: first, increase the diameter of holes, but limited by the electromagnetic attraction of electromagnets, so the development of electromagnets is also the need to strengthen threaded cartridge valves; The second is the use of pilot valve with logic main valve structure, flow amplification depends on the main valve logic valve; The third is to use a higher working pressure difference, but this is the worst policy.
3. The increase of the variety of special valves with comprehensive functions
One of the biggest features of threaded cartridge valves over other valve types is that they are easy to develop and have a short cycle. The development of this area is developed with the requirements of hydraulic applications. If the designer of the host industry is not only familiar with the process requirements of the host, but also know more about the hydraulic screw cartridge valve.
4. Improve the control accuracy of the control valve
At present, the best control accuracy of the proportional control, balance valve, diverter valve, etc. of the threaded cartridge valve is not as good as that of the plate valve. From the point of view of the threaded cartridge proportional valve produced by most screw cartridge valve manufacturers, the hysteresis is 3-10%, the frequency response (-3db) is below 10-25Hz, and the linearity is an order of magnitude worse than that of the plate valve. This is because the main market of threaded cartridge valves is still construction machinery, and the control accuracy of the load requirements is not high, which can meet the basic requirements. However, to enter the field of industrial hydraulics, this control accuracy can not meet the requirements, so there is still a lot of room for development.
5. Put forward more material research requirements and enter the field of water hydraulics
The material availability of threaded cartridge valves is closely related to product performance and life, unlike plate valves that have been finalized. It needs further study. The development of stainless steel, non-ferrous metals, surface treatment and other materials or processes, so that the screw cartridge valve into the water hydraulic and other fields. Because the threaded cartridge valve gets rid of the constraint of the valve body, it has more room for application in the material, and is a good alternative valve for water hydraulic and other occasions in the future.
6. Bus technology and other new technologies into the electromagnetic control valve
The era of bus technology has arrived, and at present, multinational enterprises have developed bus communication control systems that can be used for all hydraulic components, so that the hydraulic control system has strengthened its advanced nature and reliability from the aspect of electric control. This is particularly important in engineering technology, because this is one of the directions of the development of construction machinery. At present, the awareness gap between Chinese enterprises in this aspect is very far.
7. Development of digital control technology
Most of the current digital valves are threaded insert structure, because the digital valve is mainly used as a pilot valve, the diameter is small, more suitable for threaded insert structure. It is also one of the directions to seek new control methods that are easier to combine with computer technology and are reliable and cheap in the future.
