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Ammonia Pressure Measurement using Thermal Flash Protection

From American Sensor Technologies, Inc. - AST
 

 

Situation: Ammonia offers refrigeration pump and compressor manufacturers an improved efficiency over Freon based systems. However, the thermodynamic behavior of ammonia is very different from Freon. When the refrigeration pump turns on, the ammonia temperature rapidly changes from 100°F to -70°F or below. This accelerated change, along with the type of sensor diaphragm material affects the pressure transducer performance and ultimately the control system.

Other Pressure Sensing Technologies: O-ring sealed pressure sensors cannot withstand rapid thermal changes and over time the internal O-ring will fail. Fluid filled sensors suffer from freezing effects. This causes a rupture of the thin diaphragm membrane, which is welded in place to hold in the silicone oil-fill. Thin film sensors [based on 15-5 and 17-4PH stainless steels] that have their diaphragm welded to a pressure port, will undergo thermal stresses that will eventually crack the steel.

Products & Services
Pressure switches are actuated by a change in the pressure of a liquid or gas.  They activate electromechanical or solid-state switches upon reaching a specific pressure level. Search by Specification | Learn more about Pressure Switches
Pressure gauges are used for a variety of industrial and application-specific pressure monitoring applications.  Uses include visual monitoring of air and gas pressure for compressors, vacuum equipment, process lines and specialty tank applications such as medical gas cylinders and fire extinguishers. Search by Specification | Learn more about Pressure Gauges
Digital pressure gauges use electronic components to convert applied pressure into usable signals. The gauge readout has a digital numerical display. Search by Specification | Learn more about Digital Pressure Gauges
Pressure sensors include all sensors, transducers and elements that produce an electrical signal proportional to pressure or changes in pressure. Search by Specification | Learn more about Pressure Sensors
Product Announcements
American Sensor Technologies, Inc. - AST - 0.1% BFSL Accuracy Pressure Transducer
American Sensor Technologies, Inc. (AST) unveils the new 0.1% accuracy digitally compensated, AST20HA high accuracy pressure transducer to complement it's existing OEM and Hazardous Area pressure... (read more)
American Sensor Technologies, Inc. - AST - Single Seal Compliance For Explosion-Proof Series
American Sensor Technologies, Inc announces its compliance to ANSI/ISA 12.27.01-2003 for their AST4600 Explosionproof Pressure Transmitter. ANSI/ISA - 12.27.01-2003 "provides specific requirements for... (read more)
American Sensor Technologies, Inc. - AST - Submersible Level Sensor - Flush Diaphragm
Mt. Olive, NJ. - October 15, 2008. American Sensor Technologies, Inc. (AST) offers a Media Isolated Submersible Pressure Sensor with a Flush Diaphragm Steel Cage design, the AST4520. Featuring all... (read more)
American Sensor Technologies, Inc. - AST - AccuGauge Digital Pressure Gauge
The AccuGauge is a media compatible digital pressure gauge featuring multiple units, min/max readings, selectable tare/zero and automatic power off to conserve battery power. A backlight provides... (read more)
American Sensor Technologies, Inc. - AST - AST4800 Miniature Pressure Sensor
American Sensor Technologies, Inc (AST) provides a miniature stainless steel Pressure Sensor, the AST4800. With an overall length of less than two inches and a diameter of 0.7 inches, this model is... (read more)
WIKA Instrument Corporation - Refrigeration & HVAC Pressure Transmitter WIKA R-1
The R-1 pressure transmitter is optimally suited to the special requirements of refrigeration and HVAC applications. Its monolithic design eliminates the need for seals on the process connection. This... (read more)
American Sensor Technologies, Inc. - AST - Explosionproof Pressure Transmitter - 0.1% BFSL
American Sensor Technologies, Inc. (AST) Explosion-Proof Pressure Transmitter: The AST46HA is an Explosion Proof Pressure Transmitter or Pressure Transducer with Digital Compensation and Single Seal... (read more)
American Sensor Technologies, Inc. - AST - Low Cost OEM Pressure Transducer - AST4100
American Sensor Technologies, Inc. (AST) offers a low-cost, high-quality OEM pressure sensor built to address applications with tight space restrictions and requirements for high accuracy,... (read more)
Servoflo Corporation - Small Rugged OEM Pressure Sensor
The MPM280 pressure sensor comes in various packages for harsh pressure measurements. The pressure measurement range is up to 35 MPa. Assembled, Welded, Flush Diaphragm, Anti-Corrosive, and Gauge with... (read more)
 
Topics of Interest
Dr. Tamboli J.A. Dr. Tamboli J.A. is Ph.D. in Mechanical Engineering and has 23 years of teaching experience. He has published fourteen research papers and an e-book named FEA of Connecting Rods. (Read More)
Chapter List Chapter 11: Refrigeration Chapter 12: Gasification Chapter 13: Gas Treating Chapter 14: Vacuum Systems Chapter 15: Pneumatic Conveying Chapter 16: Blending Types of... (Read More)
A-1 PROCESS FLOW DIAGRAMS USING VISIO 2002 SOFTWARE Figure 1-12b Process flow diagram (Feed and fuel desulfurization section). Figure 1-12c Typical process flow diagram for the production of... (Read More)
Sensors are devices that monitor changes or variations in an object or process relative to a reference standard. Depending on their intended function, they can recognize changes in weight, vibration,... (Read More)
15.8 Vessel Rupture In certain circumstances a vessel may rupture completely. If vessel rupture occurs, a large vapour cloud can be formed very rapidly. Accounts of vessel rupture include those by... (Read More)
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