Panametrics BWT System, Руководство по установке, Страница: 10 / 58

Chapter 1. General Information
2 BWT™ System Installation Guide
• Non-Flanged BWT Buffer (part number FSPA ) - is used in liquid applications and has
a 1 in. NPT thread.
• Socket-Weld BWT Buffer (part number FWPA ) - is used in liquid applications and has
a 1 in. coupling that is welded into the pipe coupling.
1.3 General Guidelines for Transducer Position and Location
Whichever transducer type is selected for your installation, flowmeter accuracy depends on proper transducer
location, spacing, alignment, and electronics programming. However, even though every transducer installation has
specific location considerations, the following location guidelines apply to all transducers, regardless of type:
1. To help assure a uniform flow profile, locate the buffers so that there are at least 10 pipe diameters of straight,
undisturbed flow upstream and 5 pipe diameters of straight, undisturbed flow downstream from the point of
measurement. The more straight run available the better. “Undisturbed flow” means avoiding sources of
turbulence such as valves, flanges, and elbows. You should also avoid swirl, cross flow and cavitation (in liquids).
2. It is important to locate the transducers on a horizontal plane. This specifically applies to mounting transducers
on a horizontal pipe. One transducer cannot be on top of the pipe and one on the bottom, because the top of the
pipe tends to accumulate gas (in liquids) and the bottom tends to accumulate sediment (in gas and liquids).
These contaminants can attenuate or block the ultrasonic signal. There is no similar restriction with vertical
pipes. However, in liquid applications you should avoid vertical downward flow to ensure a full pipe.
WARNING!
For installations in potentially hazardous areas, be sure to read the Certification and
Safety Statements
document at the end of this manual before beginning the
installation.
CAUTION!
A flowmeter’s accuracy and performance depends on the location, spacing, and
alignment of the transducers. The specific spacing of your transducers are unique to
your installation.