The main type of PD meter used for gas flows is the diaphragm meter
Sensus says its patent-pending accuWAVE[TM] diaphragm meter
design will be available on the model 415, Class 400 meter in mid-2010.
To overcome these disadvantages, a diaphragm meter
has been coupled with an MIU (Figure 2), a modified, electronic secondary element of a new generation equipped with a microprocessor.
The major areas of GRI-funded flow research being conducted at the MRF include orifice and turbine meters, ultrasonic flowmeters, gas-sampling methods, and diaphragm meter
The first "dry" gas diaphragm meter
was invented in 1843 by Thomas Glover.
Again, meters were placed in real world measurement applications, in series with a comparison rotary or diaphragm meter
equipped with a corrector and data logger.
600 250 CF diaphragm meter
w/ temperature compensation; 25 400-450 CF diaphragm meter
w/ temperature compensation & 25 psi MAOP & connection set; 25 600-650 CF diaphragm meter
w/ temperature compensation & 25 psi MAOP & connection set; 20 800 CF diaphragm meter
w/ temperature compensation & 25 psi MAOP & connection set, 20 1000 CF diaphragm meter
w/ temperature compensation & 25 psi MAOP & connection set, 2 1400 CF diaphragm meter
w/ temperature compensation & 100 psi MAOP & connection set.
The first two meters were one of each ultrasonic design and the third meter, which was used for billing, was a new specially calibrated diaphragm meter
with a pulse output.
Trying to come up with a much smaller alternative that is as accurate as the traditional diaphragm meter
but incorporates microprocessor technology is difficult because they tend to be more expensive, so gas utilities are reluctant to utilize them in a big way.
This assessment, through the application of reverse engineering, resulted in developing an estimate of the relative manufacturing cost, reliability, and metering accuracy of each technology normalized to a reference diaphragm meter
, the Rockwell S-275.
The diaphragm meter
has been used by the gas industry since the mid 1800s and is able to maintain a high degree of accuracy for period of approximately 20 years.
One of the biggest goals has been to make our meters more compact and lighter weight and although this is all the talk these days with residential meters, we have been downsizing our diaphragm meter
line since 1989.