What Are Pneumatic Actuators?

rack and pinion actuator
Internal view of rack and pinion actuator
(Flowserve Worcester)
Pneumatic valve actuators are used in extreme conditions in many industries such as oil and gas, chemical, water and wastewater, bulk storage, pulp & paper, and power generation. These devices are used in a multitude of valve control processes for regulation (or cessation) of flow, controlling pressure and adjusting level.  Due to their reliability and simplicity, pneumatic actuators are one of the most popular types of actuators used in industry today.

Pneumatic valve actuators work by conversion of air pressure into motion. The device applies a force of air to a diaphragm, rotary vane, or piston that is attached to the actuator shaft, which is then mechanically connected to the stem of the valve or damper. Depending on the type, pneumatic actuators produce either linear or rotary motion. 

ACTUATOR ACTION - SPRING RETURN OR DOUBLE ACTING

Spring Return — Pneumatic actuators with spring return design have air supplied from one side. The spring on the opposite side is responsible for the motion. With this design, air compression moves the opens or shuts the valves while the spring is responsible for the opposite motion. 

Double Acting  — Double acting actuators have air fed on both sides of a piston. The pressure on one side is higher as compared to the other that results in the required in movement. Air is used to open and close the valves.  

Diaphragm actuator
Diaphragm actuator
(Samson)
PNEUMATIC ACTUATOR DESIGNS

Diaphragm Actuators — Diaphragm actuators work by applying pressure to a thin membrane or diaphragm. 

Piston Actuators — Piston actuators apply compress air to a piston that is within a cylinder. Air is fed into a chamber that moves the piston in one direction. The piston moves in the opposite direction when air pressure is removed (spring assisted) or directed to the other side (double acting). 

Rack and Pinion — Rack and pinion actuators produce rotation by applying pressure to pistons with gears that turn a pinion gear. Rack and pinion actuators can be spring return or double acting. They are valued because of their compact size and versatility.

Scotch Yoke — A scotch-yoke actuator contains a piston, yoke, connecting shaft, and rotary pin.
Scotch yoke actuator
Scotch yoke actuator
(Samson)
They can be direct acting or spring return. They are capable of providing very high torque outputs and are generally used on larger valves. Scotch yoke actuators can be powered by air or process gas.

Rotary Vane —Vane actuators use a mechanical vane, connected to a shaft, that separates a circular shaped body in two "clamshell" halves. The vane moves in response to the differential pressure inside the actuator body, turning the shaft clockwise or counter-clockwise in response to the pressure differential. External springs units are available for spring return models.

BENEFITS OF PNEUMATIC ACTUATORS

The use of compressed air (typically found in all industrial facilities) as the power source is the prime advantage for the use of pneumatic actuators. Additionally, pneumatic actuators have an advantage in suitability for different environments and can be used in extremes temperatures. They are preferred over electrical actuators in explosive, flammable and other hazardous areas because they do not require electricity (a possible ignition source) to operate. They do not create electrical fields or electrical noise since there is no electrical motor. Pneumatic valve actuators are faster opening and closing compared to their electric counterparts. Finally, they are low cost, lightweight, durable, require little maintenance (depending on quality) and there are a myriad of positioning controls, speed controls, and communications devices available for tailoring the actuator to the application.

DRAWBACKS OF PNEUMATIC ACTUATORS

While compressed air is the main reason for using pneumatic actuators, it can also be considered a drawback. For instance, pneumatic actuators can perform poorly when the air supply source is located at a distance, resulting in lag and slow response. Another drawback of pneumatic actuators is the additional cost for the compressed air system due to the requirement of dust filters and moisture removing dryers. These are required to ensure clean air is fed into the system.

APPLYING PNEUMATIC ACTUATORS

There are many aspects to the proper, safe, and efficient application of pneumatic actuators to valves and dampers. Sizing the power output (torque) being paramount. All valves and dampers have unique torque requirements. You must consider a threshold force for opening (breakaway), as the valve continues to move to its open or closed position, and then for seating. Matching the actuators to the valve type, and operating conditions is critical. Published torque curves must be reviewed and understood. Too little torque and the vale will not respond. Too much torque increases cost and can damage the valve. Spring return adds to this complexity. Considering all this, it is strongly suggested you always discuss any valve actuation requirement with an experienced applications expert. They will ensure the proper, safe, and cost effective mating of pneumatic actuator to valve or damper.

What Is IIOT? Understanding Industrial IoT and the Technology Behind It

What Is IIOT
IoT or the internet of things needs no introduction. However, you may want to familiarize yourself with its offshoots such as the Industrial IoT, better known as IIoT. The simplest way to define IIoT would be the implementation of IoT capabilities in an industrial or manufacturing setting.

An amalgamation of various technologies such as big data, machine learning, automation, and sensor data, industrial IoT enables a connected enterprise by combing the information and operational department of the industry. Let’s take a more detailed look at IIoT and the technology behind it.

Understanding IoT

A sector that is rapidly progressing and accounts for a major share in the global IoT spending, IIoT provides manufacturers and industrialists with a significant opportunity to not only monitor but also automate many complex manufacturing/industrial processes. IIoT, a network of connected devices, enables systems to collect, track, disseminate, and analyze valuable new insights.

With these insights, industrial companies can make smarter, faster business decisions. By changing how industries work, IIoT is transforming them. Additionally, businesses are getting desired outcomes by integrating IIoT with other technological solutions. This includes providing production data in real time to unveil additional plant capacity, stopping cyber-attacks through increased visibility or control over the industrial control systems, and allowing identification of corrosion within a refinery pipe through predictive analytics.

IIoT is driving incredible levels of efficiency, productivity, and performance by combining technology, industrial big data analytics, cyber security, and machine-to-machine (M2M) communication. And, this has helped bring transformative operational and financial benefits to companies in the healthcare, aviation, manufacturing, oil & gas and power & energy sectors.

The Future of IIOT

It is predicted that the industrial internet could be worth over $200 billion by 2030. This is the reasons many companies have invested heavily in the industrial internet. Example of this is the Industrial Internet Consortium—an association founded companies to accelerate the development, adoption, and widespread use of interconnected people, machines and devices and intelligent analytics.

SIEMENS is helping drive the industrial transformation by leveraging the potential of the industrial internet. The company predicts that in the future, IIoT will account for a major share of the global economy and will impact both energy production and energy consumption. Today, industries are making all sorts of efforts to modernize systems and equipment to meet new regulations, keep up with increasing speed and volatility of the market and deal with disruptive technologies.

Significant improvements to efficiency, safety, and profitability have been experienced by businesses that have embraced IIoT and this trend is expected to continue in the future as IoT technologies are more widely adopted.

If you want to learn more about IIoT, contact Ives Equipment. The can be reached by visiting https://ivesequipment.com or by calling (877) 768-1600.

Heat Exchangers for Hygienic Use

Alfa Laval provides the widest range of hygienic products and accessories in the world. Designed for superior safety, efficiency and cleanliness, they ensure careful product handling in the food, dairy, beverage, biotech, pharmaceutical and personal care industries. Alfa Laval heat exchangers, valves, automation, pumps, tank equipment and installation material offer solutions for all process stages – and almost certainly the solution you need.

Alfa Laval heat exchangers are designed for heating and cooling, pasteurization and utility duties, and are able to handle even viscous products. By combining Alfa Laval thermal technologies with their many years of industrial experience, Alfa Laval can also provide you with a wide range of tailored solutions.



Ives Equipment
https://ivesequipment.com
(877) 768-1600 

White Paper: Breakthrough Solenoid Valve Technology for Upstream Oil and Gas Heating Equipment

Low-temperature stainless steel fuel shutoff valves are usually utilized for on/off control of fuel gas
within gas fuel trains in process heating system burners. These systems are widely used by oil and gas firms as well by as original equipment manufacturers (OEMs) that produce gas heating equipment or burner management systems (BMSs) and controls in upstream oil and gas pipelines and tanks.

In recent years, a new generation of solenoid valve technology has been changing the shutoff valve game. Their modern designs provide pipeline and tank heating systems with robust, durable performance; safety; and regulatory compliance — all while increasing efficiency and productivity.

Many operators in North America and beyond are moving away from using pneumatically operated shutoff valves on their pipelines and tank heaters. They’re replacing them instead with valves introduced within the last decade by a few manufacturers — all based on solenoid shutoff valve technologies. White paper courtesy of ASCO.


Reversing the Failure Mode of a SAMSON 3271/3277 Actuator from Fail Open to Fail Close


INSTRUCTIONS

WARNING: Actuators with preloaded springs are under tension. They can be identified by three long bolts protruding from the bottom of the actuator. These should be removed last, and installed first upon re-assembly.
  1. With the actuator removed from the valve, unscrew the nuts and bolts on the diaphragm case.
  2. Lift off the top diaphragm case.
  3. Remove the diaphragm plate assembly consisting of the diaphragm plate, diaphragm, and actuator stem from the actuator case.
  4. Remove the springs.
  5. Clamp the bottom section of the actuator stem into a vise using protective jaws, ensuring the actuator stem is not damaged.
  6. Remove the collar nut.
  7. Remove the diaphragm plate from the actuator stem, flip upside-down and place them back onto the actuator stem.
  8. Re-install the collar nut.
  9. If necessary, apply a suitable lubricant to the actuator stem.
  10. Install the diaphragm plate assembly together with the actuator stem pointing downward into the bottom diaphragm case.
  11. Place the springs onto the diaphragm plate, centering them in the intended recesses. The final actuator spring range will determine the appropriate springs to be installed.
  12. Place the top of the actuator case onto the assembly. Ensure that the air connections on the cases are correctly aligned with each other.
  13. Fasten the top and bottom diaphragm cases together using the nuts and bolts. Observe tightening torques.
ABOUT THE SAMSON 3271/3277

The Type 3271 pneumatic rolling diaphragm actuator is designed for all industrial applications. This actuator is a linear motion device ideal for valve sizes ranging from the micro-flow valves to large 20"+ globe control valves.

The Type 3277 pneumatic rolling diaphragm actuator with an integrated accessory attachment area is designed for all industrial applications. This actuator is a linear motion device ideal for valve sizes ranging from the micro-flow valves to 4" globe control valves.

The thrust force of the actuator depends on the actuator area, pneumatic supply pressure, spring stiffness, distance traveled, initial compression of the spring, the number of springs internal to the actuator, etc.

The Type 3271 and Type 3277 Pneumatic Actuators contain a rolling diaphragm and internal springs and have the following special features:
  • Low overall height
  • Powerful thrust at high stroking speed
  • Low friction
  • Various bench ranges by varying the number of springs or
  • their compression
  • No special tools required to change the bench range or to
  • reverse the direction of action (also version with handwheel)
  • Permissible operating temperatures from –60 to +120 °C
For more information on SAMSON Controls, contact Ives Equipment by calling 877-768-1600 or visiting https://ivesequipment.com.

Qualified US Navy Supplier of Valves, Instrumentation, and Analyzers

Ives Equipment, headquartered in King of Prussia, PA, is a qualified US Navy supplier of valves, instrumentation, and analyzers.

As an authorized ASCO, Worcester Valve, Niagara Meter (Venture Measurement), Siemens, and REOTEMP, Ives Equipment is registered under Cage Codes 1H855 and 6F024.

Ives Equipment provides the United State Navy with these products:
  • Manual ball valves ¼” through 2”
  • Pneumatic and electric control valves 1” through 2”
  • Flowmeters ½” through 12”
  • Solenoid valves all sizes 
  • Dual temperature elements
  • Pressure transmitters
  • Temperature transmitters
  • Boiler cameras
  • RTD assemblies
Ives Equipment products meet the following United States Military Standards:
  • MIL-STD-167 valves
  • MIL-STD-167 flow meters
  • Mil-Spec qualified high shock MIL-901D
  • MIL-SPEC Pneumatic and electric control valves
Services provided to the US Navy include:
  • Complete project management / engineering for ShipAlt and MachAlt projects.
  • Wide variety or instrumentation and valving approved to Mil Spec Mil-S-901D Grade A and Mil-STD-167-1.
  • Comprehensive solutions engineering for shipboard applications.
  • Successful shipboard engineering solutions within steam machinery, chilled water, bleed air, refrigeration HVAC, life safety.
Manufacturers:

ASCO Valve Authorized Navy Distributor - ASCO designs and manufactures quality solenoid valves to control the flow of air, gas, water, oil and steam. ASCO's Navy/Marine product line represents a select line of valves designed to meet US Navy specifications.

SIEMENS - Pressure, differential pressure, temperature and level transmitters for US Navy ships.

Worcester Valve (Division of Flowserve) - Having earned a reputation over 45 years for high performance and reliability, Worcester ball valves are installed on submarines and surface ships throughout the world. Their product range of materials includes Nickel Aluminum Bronze (NAB), Monel and Titanium.

Niagara Meters (Venture Measurement) - Niagara Meters is known for their robust and proven flow meter designs. Niagara Meters’ flow meter technology is used by the US Navy for operation on naval ships. Niagara Meters is proud to be a company built on innovation and reliability for which the brand has become known.

REOTEMP - Resistance temperature detector (RTD) assemblies used aboard US Navy ships.