Dwyer PE - Manual

Series PE Orifice Plate Flow Meter
Specifications - Installation and Operating Instructions
Bulletin F-PE
The Series PE Orifice Plate Flow Meter offers one-piece PVC
construction incorporating a unique holder or carrier ring containing
metering taps and integral gaskets. Unlike a standard orifice plate, the
Series PE is a true primary element including the various components
for differential pressure measurement. It was designed for use
wherever there is an application for a conventional flow orifice plate. It
can also be used in place of other primary differential producers for
efficiency and cost effectiveness. The Series PE is available in line sizes
from 1/2˝ to 24˝ and can be used with air and compatible gases. It
meets or exceeds ASME, AGA & ISO standards.
ACCURACY
The Series PE utilizes the corner tap proportions as defined in ISO
5167. While this code may not be referred to as International Standard
until accepted by the ISO Council, the ASME Fluid Meters Research
Committee has suggested that the dimensionless coefficient equation
developed by the International Standards Organization (ISO) and
presented in ISO 5167 is significantly better for the broad spectrum of
flow measurement applications throughout process industries.
The coefficient values used in the Series PE bore calculations
represent the same confidence level assigned to the flange and radius
taps widely accepted in fluid flow measurement.
The accuracy assigned to the coefficient values is ±0.6% full scale for
d/D (Beta) values 0.2 to 0.6 and ±0.7% for Beta values 0.7 to 0.75 (i.e.
ß of 0.7 would have an uncertainty value of ±0.7% full scale).
Accuracy of the differential signal produced by the PE equals that of a
properly manufactured and installed flange or radius tap orifice meter.
MOUNTING
The orifice metering primary shall be suitable for installation between
standard ANSI 125#/150# PVC or steel flanges mounted on HDPE,
PVC or steel pipe. The unit shall be "self centering" within the bolt
circle of the flanges. No alignment of the orifice shall be necessary.
Drilling and or tapping of the main or flanges will not be allowed or
required. The overall laying length shall be 1.25˝ including pre-attached
ring type 1/8˝ thick Buna "N" Gaskets. Flange bolts should be 1.25˝
longer than standard flange bolts.
Pipe Requirements: Upstream and downstream pipe requirements
are contingent upon two factors: (a) Beta Ratio-ratio of the orifice bore
to the pipe ID (d/D); (b) The type of fitting or disturbance upstream of
the PE. For most applications, 10 pipe dia. upstream & 5 dia.
downstream are sufficient. (5 pipe dia. up and 2 dia. down are
acceptable for non-critical applications.)
Installation Tips: (a) If possible, do not install a valve upstream if it is
going to be throttled. Install on the downstream a minimum of 6
diameters from the PE. (b) The use of straightening vanes is not
necessary for most applications.
Installation: (a) Insert bolts through bottom half of the flange bolt
circle. (b) Slide PE between flanges (make sure arrow on PE faces in
the direction of flow). (c) Make sure pressure connections are properly
positioned. For horizontal air or gas lines, install with the connections
on or above the horizontal center line. They should also be correctly
oriented so as to not be blocked by bolts when remainder of bolts are
inserted. (d) Add rest of bolts and nuts leaving all bolts loose so PE is
free to move. (e) If necessary, the PE can be centered using a steel
ruler to measure the total side to side movement and set PE at half
way point all around. (f) Lubricate & tighten bolts diametrically
alternating to recommend flange torque. (g) Check to insure the PE is
installed with the arrow facing in the same direction as flow.
OVERALL PRESSURE LOSS ACROSS SERIES PE ORIFICES
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: 219/872-9057 e-mail: [email protected]
SPECIFICATIONS
Service: Clean air and compatible gases.
Wetted Material: Monolithic (single piece) constructed entirely of
gray PVC.
Accuracy: ±0.6% full scale flow (Beta = .2-.6) ±0.7% for Beta greater
than .6.
Temperature: 140°F max (60°C max).
Pressure: 150 psi max.
Head Loss: 1-Beta ratio
2 eg: 1 - 0.7 2 = 1 - 0.49 = 51% of the d.p.
Line Sizes: 1/2˝ to 24˝.
Process Connections: 1/4˝ female NPT.
Installation: Standard flange 125#/150# rating.
Pipe Requirements: General requirements 10 diameter upstream
and 5 diameter downstream.
Weight: Varies with line size. See chart.
INCLUDES RING GASKET
ADHERED TO FACES
1-1/4
(31.75)
BODY
(CARRIER RING)
ORIFICE PLATE
1/8 (3.18)
THICK TYPICAL
1/4˝ NPT PRESSURE FITTING
FLOW
HI
PRESSURE
LOW
PRESSURE
4-1/2
(114.3)
A
A
CL
CL
OD ID
F-PE:F-PE bulletin 8/17/09 1:31 PM Page 1