There are mainly the following places:
1, when the fluid flow in pipes have change, such as increasing or decreasing, velocity requirements haven't changed much, all needs to use reducer.
2, pump imports, in order to prevent cavitation.
3, and instrumentation, such as flow meter, the regulator shall, in order to cooperate with the joint of the instrument, also need to use reducer.
The installation of the pump inlet pipe diameter should make gas accumulation is not variable diameter, avoid the cavitation erosion due to improper installation. The level of the pump inlet pipe diameter changes, should choose eccentric reducer. When the level of pipe from the bottom up into the pump, reducer should take "top level"; When the pipe from the top level down into the pump, reducer should take "flat"
To prevent gas accumulation in pump inlet variable diameter tube place, eccentric reducer is used in a "flat top" installations, even if a pipe from the top level down into the pump.
Result with the end or side suction pump, when the suction speed is lower than the sedimentation rate of impurities, variable diameter tube shall be "flat"
Insert the tank orifice diameter are the same. The same water tank in different combination of vacuum tube insertion, can assemble seven different thermal properties of water heater, the pipe diameter as long as posing as a sample, can represent the seven kinds of models, its performance is poor, poor price be clear at a glance, for a vast amount of solar energy water heater pioneered the standardization. By reducing mill technology of water heater, regardless of spring, summer, autumn and winter seasons change, even in cloudy weather, rain, snow, also because of its high efficiency and has the characteristics of a good hot bath temperature reached first. At the same time, the more significant effect of energy conservation and emissions reduction, by reducing close technical water heater thermal efficiency can reach 73%, power saving, coal saving, and reduce carbon emissions.
Can according to their own actual flow process piping corresponding to the flow chart to choose appropriate diameter specifications of the flowmeter, choose as far as possible the same as the process piping diameter specifications of the flowmeter.
On both ends of the reducer is also called the head size, nozzle diameter, used to connect different diameter tubes or variable diameter flange. Concentric reducer at both ends of the tube, circle, on the same axis diameter changes, in terms of axis of pipe position, the position of the pipe is changeless, commonly used in gas or liquid vertical pipe diameter changes. Eccentric reducer ends cut inside nozzle circumference, commonly used in horizontal liquid pipeline. Eccentric reducer nozzle tangent point upward, known as the roof installation, commonly used in pump suction, exhaust, cutting down as bottom flat installation, generally used for valve installation, use the net. Concentric reducer is advantageous to the fluid flow, at the time of variable diameter less interference on the fluid flow pattern, therefore vertical flow of gas and liquid pipelines using concentric reducer. Eccentric reducer with a side is flat, favors the exhaust or drainage, convenient driving and maintenance, so the horizontal liquid pipeline with eccentric reducer in general.
Reducing pipe roundness should not be greater than 1% of the corresponding end diameter, and the allowable deviation of plus or minus 3 mm; Reducer size deviation should be allowed to meet the provisions of the table 4.2.2-3.
Source: Zhejiang Yaang Pipe Industry Co., Limited (www.yaang.com)
