With the development of foreign large-scale complete sets of technology, a series of new types of equipment and stand-alone machines have emerged. The development of new types of equipment related to valves is characterized by large-scale, high-parameter, high-performance automation and complete sets, which are compatible with the control methods of these complete sets of equipment.
In the past 20 years, the control methods of foreign valves have also developed greatly. In addition to general manual, mobile, electric, pneumatic, hydraulic drive, electro-hydraulic linkage, gas-liquid linkage, automatic control of the valve species continue to increase, and there is a trend of further development. Such as refining equipment. The largest refinery is 36.4 million tons/year (Virgin Islands in the Caribbean) and 30 million tons/year (Venezuela). At present, there are nearly 30 oil refineries with annual capacity of over 20 million tons; the capacity of the largest unit refinery pressure reduction unit has reached 24 million tons/year, the catalytic cracking unit has reached 8.24 million tons/year, and the hydrocracking unit has reached 3.2 million tons/year. year.
Larger devices have forced larger and larger valves and control methods have begun to develop in the direction of automation.
In recent years, long-distance pipelines have developed rapidly. The main reasons for this are low cost, which is equivalent to only one-third of the railway transportation; second, it is buried underground, and it is not easy to destroy; and third, the speed of pipeline construction is high and investment is low. Therefore, the demand for valves for long-distance pipelines has greatly increased in recent years.
The maximum unit capacity of power generation equipment is 1.2 million kW for twin shaft thermal power units, 1.2 million kW for single shaft thermal power units, and 1.3 million kW for the largest nuclear power unit. The diameter of the largest flat gate valve in these valves is 1620mm, 2000mm; the maximum butterfly valve diameter is 9750mm; the maximum ball valve diameter is 3050mm; the weight of the valve of the drive device is 184 tons; the valve diameter of the largest water valve is 2750mm, and the pressure reaches 9MPa.
The economic effect of large-scale equipment summed up, first, to increase production efficiency, second, to reduce infrastructure investment, and third, to reduce the consumption of raw materials. With annual refining capacity of 5 million tons of oil refining equipment and 1 million tons, the investment per ton of product production capacity is reduced by 50%. A 6-million-ton/year oil refinery compared with two 3 million-ton/year oil refineries, the investment is only equivalent to 69% of the latter, steel consumption is 53%, floor area is 54%, production cost is 75%, However, labor productivity has increased to 170%.