1. Development direction of nuclear power units According to the data analysis, in the construction of nuclear power plants, the unit capacity development direction, mainly to foreign 1.3 million, 1.4 million and 1.5 million kilowatts direction. Mainly to 800,000, 900,000 and 100 million direction of development. Nuclear power equipment will be large-scale, high-parameter, high-performance direction. 2. Nuclear Power Valve Development With the development of the nuclear industry, large-scale nuclear power plant equipment, high parameters, high performance and reliability, safety requirements are getting higher and higher. This requires nuclear power valve can adapt to this trend. The specific types of nuclear power valve development, the parameters are as follows: ⑴ gate valve without packing letter: a hydraulic drive gate valve. The valve with its own pressure to promote the piston to open or close the valve, the valve nominal diameter: DN350, 400mm; working pressure: PN17.5MPa; Operating temperature: 315 ℃. b fully enclosed electric gate valve. The valve should be a special screen-closed motor, the inner planet through the submerged planetary deceleration mechanism for the gate opening and closing movements. The valve nominal diameter: DN100 ~ 800mm; working pressure: PN2.5 ~ 45.0MPa; working temperature: 200 ~ 500 ℃. (Note: The above two kinds of fillerless gate valve advantages: no packing seal, to avoid the leakage point, while reducing energy consumption. Disadvantages: complex structure, higher cost.) ⑵ stop valve: for the auxiliary valve on the globe . The valve is usually three structures, namely, packing globe valve, bellows globe valve and metal diaphragm stop valve. The valve medium medium parameters (temperature, pressure) water and steam; nominal diameter: DN10 ~ 150mm. Butterfly valve: butterfly valve used in cooling system and system for conveying air medium in containment. The valve is usually three kinds of structure, namely the coaxial straight rubber lined butterfly valve, eccentric metal sealing butterfly valve and double acting (disc before turning off the sealing surface before turning) metal sealing butterfly valve. The valve nominal diameter: DN ≤ 2500mm; Working pressure: PN <4.0MPa; Operating temperature: 100 ~ 150 ℃. In addition, the fast closing butterfly valve used in the air duct system, its nominal diameter: DN400 ~ 1200mm also listed as the development direction. ⑷ Pilot-operated safety valve with detector: Pilot-operated safety valve with detector for nuclear island system. Pilot-operated safety valve with detector allows to change the principle of position-controlled release and charging of two contacts according to the sensitive relationship between pressure and spring force balance, so as to avoid jamming problem in structure. The valve features positive-acting disc spring preload and bellows seals to ensure a reliable seal. The valve nominal diameter: DN600mm; working pressure: PN1.265MPa. ⑸ Check valve isolation valve: check valve for steam system isolation valve, the structure similar to the lift check valve. The valve nominal diameter: DN64 ~ 800mm (21 / 2in ~ 30in); Working pressure: PN1.0 ~ 42.0MPa (Class600 ~ 2500); Operating temperature: -29 ~ 1050 ℃. ⑹ main steam isolation valve nuclear island and conventional island main steam isolation valve, the main feed valve, the nominal diameter: DN800mm; nominal pressure: 40.0MPa; temperature 700 ℃; In addition, to meet the seismic requirements of the safety valve, nuclear fuel extraction Soft and hard seal high vacuum solenoid valve, ball valve is also urgently needed to develop nuclear power valve.
Bonded Fin Heat Sink,Folded Fin Heatsink,Bonded Fin Heatsinks,Bonded Heat Sink
Suzhou Wint Electric Co., Ltd , https://www.winforthermal.com