Electricity is one of the most important energy industries. Currently there are steam, wind, hydro, geothermal, tidal power and solar power generation. This article focuses on the selection of some typical control valves in fuels, kerosene, gas and nuclear power plants. The common ground for such plants is to turn the water into steam and use the steam to drive the turbine to power the generator. The difference is that the energy used to convert the water into steam varies from natural gas to fuel oil to coal to nuclear reactors. The structure of various power plants are roughly the same. Let us take the combined cycle power plant as an example to briefly describe the selection of control valves, and then briefly explain the different parts of each power plant. Simply look at the power flow chart is actually water, steam circulation process, the selection of control valve in this process is simple and complex. Simple is the process medium is simple, only water and steam two kinds of complicated water and steam temperature and pressure fluctuations range, bringing a series of problems such as: flash, cavitation, erosion, noise, corrosion. But the first thing to consider is the safety and reliability of the control valve. We follow the system flow to expand the control valve selection instructions. Feed water main valve, auxiliary boiler feed water valve, compound type water supply control valve Control requirements: Control boiler feed water, maintain boiler liquid level and steam flow. Working conditions: When the boiler is started, the pressure difference of the valve can reach 100-300 kg, the flow rate is small, the pressure difference is smaller during normal operation, the flow rate is large, the flow rate adjustable ratio is 75: 1-100: 1. Valve requirements: body material WCB / WC9, for the two-valve system requires anti-cavitation valve start, V-level closure level, for the composite valve to be used to the characteristics of the valve parts at the same time meet the boiler startup and normal operation need. The general valve selection for the fault off, (Note that the general water to dissolve the oxygen which will join the diamine for processing, it will SATELLITE Alloy 6 or other similar alloy adverse reactions, it is best not to use 316 + STELLITE surfacing method of dealing with the valve trim, direct selection of 416 stainless steel). Boiler feed water pump minimum flow control valve requirements: the boiler feed pump to start and run safely, eliminating the flow is too small, increasing temperature, water cavitation strong pump damage. (The old power station has a minimum flow control valve that uses a switch type, along with an automatic circulation valve using a mechanical pump). Condition conditions: pressure drop of 160-350 kg, is the largest pressure drop in the power plant valve, the flow is generally 30% of normal flow. Valve requirements: anti-cavitation, anti-blocking structure, V-class seal, the pump starts and stops running continuously when the valve is working, the pump normally activated after the next valve off valve, the valve is usually open for failure. High / Low Heater Trap Feedwater Heater Drainage, Condensate Heater Drainage Control Requirement: Controls the position of condensate in the heater and promptly discharges condensate, ie, high water level discharge, normal water level. Condition conditions: the medium is saturated water, the pressure between the control valve heater is generally 6-30 kg, the last level of the trap directly connected to the condenser or deaerator. Valve requirements: Anti-flash flushing, V or VI-level seal, the valve is usually open fault. Deaerator water level control valve (DALC) control requirements: to provide flow to maintain the normal deaerator water level, by adding steam to increase the water temperature to eliminate dissolved in water gas. Condition conditions: Start phase flow is smaller, the pressure is larger, the normal flow, pressure is small, the condition is similar to the water valve. Valve requirements: Anti-cavitation effective at lower flow rates, control valve for desuperheater (desuperheater) Control requirements: High pressure water is injected into the steam to bring the steam temperature to the control requirements. Working conditions: medium water, large pressure drop, the valve requirements: various types: nozzle type, auxiliary atomization type, self-contained type and folder type. Pressure reducing valve (high and low pressure bypass valve) Control requirements: the high temperature and high pressure steam to a certain temperature and pressure steam; to provide a bypass steam turbine, the boiler can work independently of the turbine. Condition conditions: high temperature and pressure steam temperature and pressure reduction. Valve requirements: thermal shock, noise reduction, rapid response.
The craft candle is a candle which produces all kinds of color
flame in the combustion,can as christmas candles or Wedding Candles,is also scented candles,floating candle,silver candles, and is composed of the main combustion agent, the hair
color agent and other auxiliary agent. The principle of hair color is in
accordance with some metal ions or their compounds in the heat, the molecules
in the high temperature effect, from the original orbit, the formation of
transition movement. Electrons emit the energy stored in the original when they
jump, and emit a variety of gloss, the color of the light depends on the
radiation spectrum of the substance.
The craft candle is a candle which produces all kinds of color
flame in the combustion,can as christmas candles or Wedding Candles,is also scented candles,floating candle,silver candles, and is composed of the main combustion agent, the hair
color agent and other auxiliary agent. The principle of hair color is in
accordance with some metal ions or their compounds in the heat, the molecules
in the high temperature effect, from the original orbit, the formation of
transition movement. Electrons emit the energy stored in the original when they
jump, and emit a variety of gloss, the color of the light depends on the
radiation spectrum of the substance.
1, there are a variety of burning colors: red, yellow, blue,
green, purple, etc..
2, non-toxic, no smoke, tasteless, can eliminate the smell.
3, the combustion temperature of 85 DEG C, after turnover is not
easy to burn.
4, the flame is soft, can DIY make the color of the candle body,
free combination of flame color.
5, wick combustion does not produce CO combustion gas, no
pollution to the environment.
6, for natural organic matter, easy to dissolve, with soap and
water is easy to clean.
Multi-Color Craft Candles,Christmas Candles,Scented Candles,Wedding Candles,Floating Candle,Silver Candles
HEBEI GEMMY IMP.& EXP.CO.,LTD , https://www.hebeiartcandle.com