Dwyer SSM - Manual

Series SSM All Metal Flowmeters
Specifications - Installation and Operating Instructions
Bulletin F-41-B
Series SSM 31 all Metal flowmeters are ideal for dirty or opaque
fluids, high temperature and high pressure service and harsh
environments. The direct reading scale provides ±2% accuracy.
Flowmeters can quickly be disassembled without removing the body
from the pipeline for easy cleaning.
SafetY pRecaUtionS
Personnel safety should be considered before pressurizing and
operating the system. There are numerous possibilities for error in
system operation and maintenance as well as component installation.
Because human eyes must necessarily come into close proximity with
the flowmeter to read it, Dwyer Instruments, Inc. recommends that safety
shielding such as a sheet of transparent, high impact material be used
in front of the meter. If hazardous, toxic, or flammable fluids are being
metered, recommended safeguard should include methods to protect
personnel from splash or rebound. A method of quick, safe removal of
dangerous fluids should also be included.
inStaLLation
PREPARATION: Series SSM All Metal Flowmeters are ready to install
as-is, although the sight tube may need repositioning so the scale is
visible after installation. First, remove the protective caps from the
connection ports. ALSO, REMOVE THE PLASTIC TUBING ABOVE THE
INLET CAP IN THE METER CORE TUBE! This tubing blocks the float
assembly in place during shipment. Check that the float moves freely
within the core tube, and that no packing materials are in the meter.
RecoMMenDeD pipinG
Series SSM All Metal Flowmeters generally have no special straight run
or other piping requirements. Inlet piping should be the same size as the
meter connection. Some effect on meter accuracy may occur at high
flow velocities if inlet piping guidelines are violated. Please refer to the
table on the next page. When installing on different size pipe, use
standard pipe adapters and come into the meter inlet with a nipple 8
diameters long of the same size for greatest accuracy. Control valves
should be mounted on the outlet side of the meter. The use of a three
valve manifold around the meter is suggested, as it allows uninterrupted
process flow while the meter is being cleaned.
pLUMBinG-in
While the flowmeters should be vertical, exact plumbness is not
necessary. A general rule is that if the meter appears plumb, it is close
enough (even if off by 10º, the predictable reading error is usually less
than 1%). Pipe should be cut to proper lengths to avoid stress on the
meter. Avoid over-tightening, and do no use wrenches on the body or
sight tube. If using solvents in the vicinity of polysulfone sight tubes, the
tube should be removed until fumes clear.
SURGe & WateR HaMMeR pReVention
Operating Limits are for non-shock conditions only. Flowmeters are more
accurate and less likely to be damaged when the fluid flow is smooth.
Water hammer is a hazardous phenomenon and should be eliminated
from any fluid system. Water hammer is a series of pressure shocks
create by a sudden change in the flow velocity of liquid in a pipe. This
sudden change, often caused by a fast acting valve or starting, stopping,
or change in speed of a pump, generates an immediate rise in pressure
that sometimes makes a noise similar to striking the pipe with a hammer.
The pressure wave is transmitted from the source throughout the
system, subjecting every component to the sudden shock. Pressure
returns to normal only when a larger vessel or pipe section is reached,
the energy dissipated thru friction and pipe expansion, or some
component ruptures. Rupture of piping, valves, flowmeters, or other
components have obvious safety ramifications that must be addressed.
Surge Chambers & Accumulators: Flowmeters are more accurate and
less likely to be damaged when the fluid flow is smooth. If the meter must
be installed on a line where reciprocating pumps causing pulsation are
used, surge chambers, accumulators, or desurgers are strongly
suggested to dampen the shock wave. This is a good, general practice
for all flowmeters.
SIGHT TUBE ROTATION: Series SSM All Metal Flowmeters use
magnetically-linked ball indicators and the scale usually may be
positioned over approximately a 300 ˚ range. However, the magnet
position must also be changed accordingly, requiring removal of the sight
tube (see “Disassembly”). On standard SSM All Metal Flowmeters as
depicted in Figure 1, the magnet slides out of the carrier at the top of the
float assembly. The screw holding the carrier to the float may be
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: Compatible liquids.
Wetted Material: T316 SS, Alnico magnet, FKM O-ring.
temperature Limits: 300ºF (149ºC), temperatures from 300˚F to 600°F
(149˚C to 316°C) require “hot top” sold separately.
pressure Limits: 3/4˝ models: 1000 psig (68.9 bar) @ 250ºF (121ºC),
1-1/2˝ models: 800 psig (55 bar) @ 250ºF (121ºC).
(See the chart on pg. 6 for temperature vs. pressure ratings).
accuracy: ±2% FS.
Repeatability: ±0.5% of indicated flow rate.
process connections: 3/4˝ or 1-1/2˝ female NPT.
Scale Length: 3/4˝ models: 3.2˝ (8 cm); 1-1/2˝ models: 5.2˝ (13 cm).
Weight: 3/4˝ models: 5 lb (2.3 kg); 1-1/2˝ models: 13 lb (5.9 kg).
10.780
[273]
2.810
[71.4]
2.680
[68]
4.026
[102]
3/4" NPT
Ш 1.350 [34.3]
Ш 2.754
[70]
MODEL SSM110,111,112 MODEL SSM113,115
15.640
[397]
4.503
[114]
3.710
[94]
5.695
[145]
Ш 2.480
[63]
Ш 4.010
[101.8]
1-1/2" NPT
12 40
72