Sunday, April 30, 2017

Protect Your Instrumentation with Diaphragm Seals

Flanged diaphragm seal
Flanged diaphragm seal
Pressure measurement is a common element of industrial operations and control systems. Fluid processing can often involve media that is potentially harmful to pressure sensing devices. The media may be corrosive to the sensor material, or other media properties may impact the performance or usable life of the instrument. In process control environments, diaphragm seals play a role in protecting items like pressure sensors from damage by process fluids.

The diaphragm seal is a flexible membrane that seals across the connecting path to a sensor and isolates the sensor from the process media. System pressure crosses the barrier without inhibition, enabling accurate measurement, but the process fluid does not. Typical materials composing diaphragm seals are elastomers, with a wide variety of specific materials available to accommodate almost every application.

In the operating principle of the diaphragm seal, the sealed chamber created between the diaphragm and the instrument is filled with an appropriate fluid, allowing for the transfer of pressure from the process media to the protected sensor. The seals are attached to the process by threaded, open flange, sanitary, or other connections.  Diaphragm seals are sometimes referred to as chemical seals or gauge guards. Stainless steel, Hastelloy, Monel, Inconel, and titanium are used in high pressure environments, and some materials are known to work better when paired with certain chemicals.
Threaded diaphragm seal
Threaded diaphragm seal

Sanitary processes, such as food, beverage, and pharmaceuticals, use diaphragm seals to prevent the accumulation of process fluid in pressure ports, a possible source of contamination. If such a buildup were to occur, such as milk invading and lodging in a port on a pressure gauge, the resulting contamination compromises the quality and purity of successive batches. Extremely pure process fluids, like ultra-pure water, could be contaminated by the metal surface of a process sensor. Some pneumatic systems rely on the elimination of even the smallest pressure fluctuations, and diaphragm seals prevent those by ensuring the separation of the process materials from the sensors.

Sanitary diaphragm seal with gauge
Sanitary diaphragm
seal with pressure gauge.
Diaphragm seals are not without some application concerns, and devices are now built to address and counter many potential issues related to the use of diaphragm seals with process monitoring instruments and equipment. Products seek to eliminate any and all dead space, allow for continuous process flow, and are self-cleaning thanks to continuous flow design. Some high pressure seals come equipped with anti-clogging features, accomplished by the elimination of internal cavities while protecting gauges. Multi-purpose seals reduce temperature influence and improve instrument performance while pinpointing and diffusing areas of high stress. These pre-emptive measures result
in longer instrument life-cycles and improved performance while ensuring protection from corrosion.

There are numerous options and available diaphragm seal variants. Share your application specifics with a product specialist, combining your own process knowledge and experience with their product application expertise to develop an effective solution.

Monday, April 24, 2017

Measurement and Control Instruments for the Power Industry

Control Instrumentation for Power Plants
Coal fired power plant.
The coal-fired power generation and combined-cycle power generation industry now demands much more of its control and instrumentation suppliers. Common areas for use are fuel systems, fermenters, gas storage, water treatment, boiler feed water, boiler drum, steam line, cooling water system, generator, condenser, gas cleaning system, flue gas desulfurization, residuals storage and stack.

The document below provides a visual guide of common applications and the instrumentation products that have proven track records in those applications.

Monday, April 17, 2017

Flowserve Valtek Valve Automation

The video below highlights several Swanson Flo automated Valtek control valves. Included in these systems are Valtek ShearStream segmented ball valves, Valtek Valdisk BX butterfly valves, Logix positioners, Valtek VR piston actuators, and StoneL Axiom valve monitors.

Swanson Flo is a premier valve and valve automation supplier located in Plymouth, MN with warehouse and fabrication facilities in Addison, IL, Indianapolis, IN and Menomonee Falls, WI.

Visit Swanson Flo at or call 800-288-7926 with any valve automation project.

Saturday, April 8, 2017

Swanson Flo Valve Automation Services

42 inch electrically actuated butterfly valve
42 inch electrically (Limitorque) actuated butterfly valve.
Swanson Flo, an industrial valve and control company headquartered in Plymouth, Minnesota is also one of North America's leading valve automation specialists.

From simple, small pneumatic or electrically actuated valves, to very large, critical-control valve systems, Swanson Flo delivers tested, certified, and reliable product to customers located in the Upper Mid-West. Swanson Flo designs, engineers, and assembles actuated valve assemblies for the best fit, highest performance, and optimal application life. Their engineers and technicians combine decades of experience and knowledge. Coupled with a broad variety of carefully selected, readily available components, Swanson Flo customers are provided the best quality and best value possible.

Building upon 50+ years of industry and applications experience, Swanson Flo boasts the largest, most comprehensive automation facility in the mid-west, with capabilities for electric, pneumatic and electro-hydraulic actuation. A team of experienced design engineers and fabrication technicians construct automated valve systems from virtually any valve, actuator, monitor or positioner technology.

For more information, visit or call 800-288-7926.