MULTI-POINT DENSITY ARRAY

MULTI-POINT
DENSITY ARRAY
FIXED-POINT INTERFACE PROFILING MEASUREMENT
Why Multi-Point
DENSITY ARRAY?
Leadership in Radiation-Based Measurement
Ohmart/VEGA is proud to offer the ultimate in fixed-point interface profiling
measurements, the DSG Multi-Point Density Array (MDA). Offering high
resolution and unparalleled method of measuring interfaces including those
with emulsion layers, the DSG MDA is designed to operate in the most difficult
of applications including:
• Free Water Knock Out vessels ( FWKO)
• Treaters
• De-Salters
• Low and High Temperature Separators
4
:: DENSITY ARRAY ::
Features &
BENEFITS
Accuracy and Repeatability
Ohmart/VEGA’s MDA system provides accurate and repeatable density
information, specific to each horizontal plane.
Continuous Density Output
A continuous density output is provided from each individual measurement point
providing the operator information on the density of the oil, emulsion and water.
Emulsion Detection
As these outputs change on multiple gauges, the movement of the interface and the size of the emulsion layer can be determined.
Low Maintenance
The system is low maintenance because it does not contact the process directly
(no wetted parts). Thin coatings on the source dry well will have minimal affect on
the measurement.
Uninterrupted Operation
With multiple measurement points a failure of one detector does not shut down the operation of the vessel.
Flexible Mounting Configuration
Internal structures in the vessel, such as electrostatic grids, can alter the mounting configuration, but typically can be accommodated. Additionally, external
mounting of the detectors and insertion sources can provide flexibility for future
changes in the measurement span.
Extensive Diagnostics
The use of Ohmart/VEGA’s OhmView Software program provides extensive
diagnostics of each gauge via a connection with the 4 to 20 mADC HART®
Protocol signal of each gauge. Alternatively, all gauge diagnostics can be
accessed through a single connection with OhmView via a gauge to gauge
RS485 connection.
Principles of
OPERATION
A continuous density output is provided from each individual
measurement point providing the operator information on the
density of the oil, emulsion, and water. As these outputs change
on multiple gauges, the movement of the interface and the size
of the emulsion layer can be determined.
INTERFACE WITH EMULSION LAYER
DEFINED (CLEAR) INTERFACE
6
:: DENSITY ARRAY ::
System
COMPONENTS
The MDA System Consists of 3 Components:
• Source Holders: containing a source of gamma radiation
• Radiation-based Detectors
• Operator Interface System: displays the detector outputs to indicate the process conditions
Specific selection of these various components is dependent upon each
application and the customer’s measurement purpose. Vessel size,
shape, wall thicknesses, measurement span of interest, measurement
span resolution, ambient and process temperatures, and other application
variables will determine the number and specification of the individual
components of the system.
The measurement span and resolution determine the number and orientation
of the detector array, mounted on the outside of the vessel, which determines
the source holder and source requirements (number, size, location, and
construction) normally inserted into a dry well on the vessel through a flanged
interface between the source holder and the vessel dry well. Dry wells can be
straight or curved to meet the needs of the applications.
The customer interface receives the detector outputs, generally multiple 4
to 20 mADC HART Protocol outputs and manipulates the outputs to
provide the operators with an indication of the interfaces in the vessel.
The Ohmart/VEGA MDA can simply provide multiple outputs to a distributed
control system (DCS) for a graphical indication from each gauge or combine
the signals as appropriate to provide a measure of the thickness of various
interfaces or an overall level indication.
SOURCE HOLDERS
SHLM Series of Source Holders
• Insertion type source holder for installation
on a process drywell.
• Available with a stainless steel cable or
solid rod versions
• Multiple source configuration available
• Shutter lockout (optional)
• Able to be used on high pressure or
temperature applications
8
:: DENSITY ARRAY ::
System
COMPONENTS
continued
RADIATION-BASED DETECTORS
Electronics
• The GEN2000® electronics is a modern generation of compact, light
weight, and modular electronics utilized by many Ohmart/VEGA level
and density detectors.
Cast Aluminum Compact Housing
• Light weight and compact
• Available with PVC coating for aggressive environments
Modular Electronics
• Easy maintenance
• Surface mounted component technology for increased reliability
Outputs
• 4-20 mADC with HART Protocol communications
• Foundation Fieldbus digital protocol
Universal Power Input
• Power supply can be connected to an AC or DC input
Configuration
• HART Handheld
• PC software OhmView 2000
O-ring Seal Design
• To prevent moisture infiltration and allow 360 degrees orientation, the
housing incorporates o-ring seals at the threaded connections
OPERATOR INTERFACE SYSTEM
PLC-Based Interface
As an option Ohmart/VEGA can provide a
programmable logic controller (PLC) to either
locally or remotely display the detector information.
The remotely mounted PLC can also be configured to
provide the measurement outputs back to a DCS
system via a single ModBus or ether digital signal.
• The PLC display will display individual
densities in each specific zone of measurement.
• The target densities for oil and water
can also be displayed.
• Relay outputs can provide alarming capabilities.
• A combination of point density outputs can indicate overall
vessel levels.
• The PLC system can be mounted remotely or locally
• If mounted locally, at the separator, it allows all density
measurements to be transmitted via a single ModBus or
other digital signal back to the customers control system,
thus reducing wiring requirements.
OhmView 2000 Software
User friendly English prompt software
tool for configuration, maintenance,
trending and diagnostics of the
GEN2000 series gauges.
10
:: DENSITY ARRAY ::
Training &
SERVICE
Ohmart/VEGA is able to meet all of your radiation service and
training needs. With state of the art classroom facilities, service
personnel located world wide, and a full production and service
facility, Ohmart/VEGA is always ready to provide the following:
•
•
•
•
•
•
•
24-hour emergency service phone support
Radiation survey meter calibration
Product training and system operation
Radiation safety school certification
Wipe test and wipe test analysis
Service, maintenance, and disposal of source material
Start up and commissioning
Other Ohmart/VEGA Interface
Measurement
SYSTEMS
CONTINUOUS RADAR LEVEL
The VEGAFLEX 67 is a guided microwave sensor designed to
measure the level of the interface between two liquids. The
primary output is the level of the lower liquid, but the overall
level information is available by using additional signal
conditioning instruments.
CONTINUOUS LEVEL
The FiberFlex® is the industry’s only flexible radiation level
detector and features Ohmart/VEGA’s GEN2000 family of
electronics. With its patented fiber optic scintillator bundle,
the FiberFlex has significant advantages over both solid
scintillators and traditional ion chamber detectors.
NUCLEAR INTERFACE MEASUREMENT
The SmartScan Profiler uses an integral source that is
contained within the “leg” of the unit. The source is raised
and lowered by a motor-driven tape to provide full
vessel scanning.
4170 Rosslyn Drive
Cincinnati, Ohio 45209
toll free: 1.800.FOR.LEVEL
telephone: 513.272.0131
fax: 513.272.0133
web: www.ohmartvega.com
35237-US-080703
email: info@ohmartvega.com