Emerson 3-9000-771A Manuel D’Utilisation

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Piping recommendations
Section 2: Mechanical installation
Daniel 3818 LNG Liquid Ultrasonic Meter Installation Manual
May 2012
3-9000-771 Rev A
2.3
Piping recommendations
Recommendations for best measurement results:
Honed or un-honed meter tube(s)
Flow direction (unidirectional or bidirectional)
Correct meter size selection  - too low may cause poor flow stability (thermal convection) 
or too fast may cause erosion problems and resonance,  cracks or failure of probes or 
thermowells (approximately .6 to 12 m/sec or 2 to 40 ft/sec).
Space availability for meter lengths (to allow inlet piping customization)
Concentric alignment pins or flange concentricity technique considerations  
EXPLOSION OR FIRE HAZARD
Read and follow the instructions below:
Conduit runs must have a sealing fitting within 457mm (18 inches) of the enclosure to reduce the 
risk of an explosion or a fire. 
During operation, keep covers tightly closed. DO NOT  open the transmitter electronics 
enclosures when an explosive  atmosphere may be present.
During equipment maintenance, disconnect power before opening the transmitter electronics 
enclosures. Clean cover joints before replacing. 
DO NOT substitute meter components. Substituting components  may compromise the intrinsic 
safety of the device.
Failure to follow these safety instructions may result in severe injury to personnel or cause damage to the
equipment.
For optimal flow measurement conditions, Daniel suggests the piping configurations below. Regardless of the 
configuration selected, the user agrees to accept full responsibility for the site piping design and installation.