Jun 11 2014

Features Drinking Water Measuring Instrument( Water Meter), principles, introduction and use of traditional

Measurement of water flow meter. Mostly is the cumulative flow measurement of water. Generally divided into volumetric meter and velocity meter two. The accuracy is higher than, but the high requirement of the water quality, water containing impurities easily blocked. Recording water water meter, installed in the pipe, when the user when discharging water, table rotation pointer or wheel pointed out that through the water.

Drinking Water Measuring Instrument( Water Meter)

The internal structure of the traditional water meter from the outside to the inside can be divided into the shell, the inner core sleeve, three piece. The shell is made from pig iron, water inlet out through the lower part of the annular space shell, here called “ring room”. On top of the annular space of the “upper room” and the Drinking Water Measuring Instrument( Water Meter). One with a hole at the bottom of the filter sleeve, filter water impurities. The side of the sleeve has two rows of round holes, the hole position coincided with the shell on the annular chamber to, obviously, the lower is the water inlet, outlet row is. In particular, the two rows of holes are sideways along the tangential direction round. Note on two rows of holes in the opposite direction. Water from the discharge hole along the tangential direction of flow in, will form a rotating water flow, this is very important for water works. The inner core is divided into upper, middle, lower three layers, see from the glass of the window is the upper, only the pointer and dial. In fact, the key is lower, there is a plastic wheel, there are many plastic blade wheel, called “impeller”.

Impeller location right in the rotating stream formed by the lower hole of the casing, the impact of water flow blades, wheel torque is generated, so that the rotation of the impeller. The tap was greater, the more anxious, impeller will turn faster.

The impeller shaft vertical upward to the middle, there is a small gear on a shaft, use it and “decimal gear meshing, achieve” to total revolution. “The decimal number gear” role is when the single digit gears turn ten laps, ten digit gear will turn a circle. In other words, a digit gear rotates a circle, the ten digit gear will turn 1/10 times. A number of gear are active, rely on it to drive ten digit gear. In fact, every decade with two on gear, so that the rotation direction, wherein a pair of transmission ratio is 9:30, another is 10:30, the two together, the total transmission ratio is the two product, namely 0.099999, can approximate to 0.1. According to this calculation, if you want to read (seven digits before the decimal point read four black scale after the decimal point, read three red scale), have 12 pairs of gears. Plus some other purpose, in the middle and small space into 18 shaft and 34 gears, also can be a high density mounting. This type of meter with its simple and cheap, can be used without the need to repair in damp environment, without power supply, power failure does not affect the work of the advantages will still long service.

The term:

The minimum flow rate (Q1): showing the value of the maximum permissible error meets the minimum flow requirements of water meter.

The boundary flow (Q2): appeared in between, commonly used flow Q3 and minimum flow Q1 will flow range is divided into the two region specific maximum permissible error of “high” and “low” flow.

The commonly used flow (Q3): maximum flow rated working conditions. In this flow, water meter should work normally and meet the maximum permissible error.

Overload flow (Q4): water in a short time can meet the requirements of the maximum Rotary Volumetric Piston Water Meter, maximum flow in rated working conditions can still maintain the metrological characteristics.

Pressure loss (Δ P): at a given flow rate, head loss caused by the existence of water pipeline