Showing posts with label Limitorque. Show all posts
Showing posts with label Limitorque. Show all posts

Friday, July 20, 2018

Limitorque Pneumatic Compact Scotch Yoke Actuator Model LPC

Limitorque Pneumatic Compact (LPC)
The Limitorque Pneumatic Compact (LPC) range is a robust, lightweight, modular Scotch yoke design available in both spring return and double acting configurations. It is suitable for actuating ball, butterfly and plug valves or any other quarter-turn application.

LPC compact actuators deliver up to 5500 Nm (4057 ft-lb) of precisely controlled torque. The LPC product range is complementary to the Limitorque LPS heavy-duty pneumatic Scotch yoke actuators.

A similar design philosophy to the heavy-duty LPS was applied to the new LPC range, delivering enhanced performance and high reliability. The LPC is available in standard as well as special material configurations upon request.

For more information, review the embedded document below, or you can download a PDF version of "Limitorque Model LPC Pneumatic Compact Scotch Yoke Actuator" here.

Friday, April 27, 2018

Valve Actuation 101: The Three Basic Types of Pneumatic Valve Actuator

Pneumatic valve actuators come in three basic design varieties:
  1. Scotch-yoke
  2. Rack & pinion
  3. Rotary vane
All three types provide the same function - converting air pressure to rotational movement intended to open, close, or position a quarter-turn valve (ball valves, plug valves, butterfly valves, or other 90 degree rotational valves).

All three styles are available in either direct acting or spring return versions. Direct acting actuators use the air supply to move the actuator in both directions (open and close). Spring return actuators, as the name implies, uses springs to move the actuator back to its "resting" state. Converting from direct acting to spring return is done through simple modifications, typically just adding an external spring module, or removing the end caps from rack and pinion actuators and installing several coil springs.

Scotch yoke
Scotch yoke (Limitorque)
Scotch-yoke actuators use a pneumatic piston mechanism to transfer movement to a linear push rod, that in turn engages a pivoting lever arm to provide rotation. They come in a wide variety of sizes, but are very often used on larger valves because they are capable of producing very high torque output. Spring return units have a large return spring module mounted on the opposite end of the piston mechanism working directly against the pressurized cylinder.

Rack and pinion
Rack and pinion (Delval)
A rack & pinion pneumatic actuator uses opposing pistons with integral gears to engage a pinion gear shaft to produce rotation. Rack & pinion actuators (sometimes referred to as a lunch box because of their shape) tend to be more compact than scotch yoke, have standardized mounting patterns, and produce output torques suitable for small to medium sized valves. They almost always include standard bolting and coupling patterns to directly attach a valve, solenoid, limit switch or positioner. Rack and pinion actuators use several smaller coil springs mounted internally and provide the torque to return the valve to its starting position.

Vane actuators generally provide the most space savings when comparing size-to-torque with rack and pinion and scotch yoke. They have a reputation for long life because then contain fewer moving parts than rack and pinion and scotch yoke actuators. Vane actuators use externally mounted, helically wound "clock springs" for their spring return mechanism.

The practical difference between these three types of pneumatic actuators comes down to size, power, torque curve and ease of adding peripherals. For the best selection of valve actuator for any quarter turn valve application, you should seek the advice of a qualified valve automation specialist. By doing so your valve actuation package will be optimized for safety, longevity, and performance.

Wednesday, April 4, 2018

Valve Automation Basics: Electric Actuators

Electric Actuator
Electric Actuator Assembly (Limitorque)
Electric actuators bring automation to industrial valve operation, allowing complex processes to be managed and controlled by remotely located control systems.

There are other motive forces used for valve actuators, including hydraulic and pneumatic, but electric actuators carry their own particular set of operating characteristics that make them an advantageous choice for many applications.

Valve actuators are available in uncountable variants to suit every application scenario. There are three basic valve actuation motions.

  • Multi-turn, with repeated rotations of the valve shaft needed to move the valve trim from fully open to fully closed. A gate valve is a multi-turn valve. These are also called linear, with respect to the motion of the closure element. The term "linear", in this case, refers only to the movement of the valve trim and not the flow characteristics of the valve.
  • Part Turn, where a 90 degree rotation of the valve shaft produces a change from opened to closed. Ball valves are in this category.
  • Lever, generally associated with damper control.

Electric Actuator
Completed Electrically Automated Valve
An electric actuator is a combination of motor and gearbox with sufficient torque to change valve trim position. A local self-contained control commands the motor and provides feedback to the process master controller regarding position, travel, torque, and diagnostics. Several interface options are available to facilitate communication between actuator and master controller.

There are numerous considerations to take into account when selecting an electric actuator.

  • Torque needed to effectively operate the subject valve.
  • Actuator enclosure type - wash down, hazardous area, dust, etc.
  • Service area for the assembly - corrosive environment, temperature extremes, and more
  • Valve movement - linear, multi-turn, part turn, lever
  • Operation mode - open and close only, positioning, modulating
  • Frequency or duty cycle - infrequent, frequent, or almost continuous positioning
  • Communication - How will the local controller communicate with the central control system?
  • Electrical - What electric power characteristics are available for operation?
  • Protections - Motor overload, torque limit, others
  • Process Safety - Among other things, what happens if power fails? 

There are certainly other elements to consider when applying an electric actuator for industrial use. Share your valve and actuator requirements and challenges with product specialists, combining your process knowledge with their product application expertise to forge the most effective solutions.

https://swansonflo.com
800-288-7926

Monday, March 26, 2018

Limitorque MX Actuator Users Instructions, Maintenance, and Spare Parts Manual

Flowserve Limitorque MX
The Flowserve Limitorque MX actuator controls the opening and closing travel of valves and other actuated devices. OPEN and CLOSED limits are protected by an absolute encoder that provides optical sensing of valve position and measures valve position in both motor and handwheel operation.

No battery or backup power supply is required. Output torque is derived from motor speed, temperature, and voltage. If the preset torque is exceeded, the motor shuts off. As a result of this reliable and advanced protection technology, all valve and other actuated devices are protected from potential damage from overload, improper seating, and foreign obstructions.

A range of control and network options is available and can be easily added to the control capabilities already available on a standard actuator.

You can download the Limitorque MX Electronic Actuator User Instructions, Maintenance, and Spare Parts Manual in PDF version from the Swanson Flo site here (8.5MB), or read the embedded version below.

Thursday, December 28, 2017

Industrial Valve Actuators: An Overview

Pneumatic Actuator
Pneumatic Actuator
(Limitorque)
Valves are essential to industries which constitute the backbone of the modern world. The prevalence of valves in engineering, mechanics, and science demands that each individual valve performs to a certain standard. Just as the valve itself is a key component of a larger system, the valve actuator is as important to the valve as the valve is to the industry in which it functions. Actuators are powered mechanisms that position valves between open and closed states; the actuators are controllable either by manual control or as part of an automated control loop, where the actuator responds to a remote control signal. Depending on the valve and actuator combination, valves of different types can be closed, fully open, or somewhere in-between. Current actuation technology allows for remote indication of valve position, as well as other diagnostic and operational information. Regardless of its source of power, be it electric, hydraulic, pneumatic, or another, all actuators produce either linear or rotary motion under the command of a control source.

Thanks to actuators, multiple valves can be controlled in a process system in a coordinated fashion; imagine if, in a large industrial environment, engineers had to physically adjust every valve via a hand wheel or lever! While that manual arrangement may create jobs, it is, unfortunately, completely impractical from a logistical and economic perspective. Actuators enable automation to be applied to valve operation.
Electric actuator
Electric Actuator
(Limitorque)

Pneumatic actuators utilize air pressure as the motive force which changes the position of a valve. Pressurized-liquid reliant devices are known as hydraulic actuators. Electric actuators, either motor driven or solenoid operated, rely on electric power to drive the valve trim into position. With controllers constantly monitoring a process, evaluating inputs, changes in valve position can be remotely controlled to provide the needed response to maintain the desired process condition.

Large butterfly valve with actuator
Large butterfly valve with actuator.
Manual operation and regulation of valves is becoming less prevalent as automation continues to gain traction throughout every industry. Valve actuators serve as the interface between the control intelligence and the physical movement of the valve. The timeliness and automation advantages of the valve actuators also serve as an immense help in risk mitigation, where, as long as the system is functioning correctly, critical calamities in either environmental conditions or to a facility can be pre-empted and quickly prevented. Generally speaking, manual actuators rely on hand operation of levers, gears, or wheels, but valves which are frequently changed (or which exist in remote areas) benefit from an automatic actuator with an external power source for a myriad of practical reasons, most pressingly being located in an area mostly impractical for manual operation or complicated by hazardous conditions.

Thanks to their versatility and stratified uses, actuators serve as industrial keystones to, arguably, one of the most important control elements of industries around the world. Just as industries are the backbones of societies, valves are key building blocks to industrial processes, with actuators as an invaluable device ensuring both safe and precise operation.

Saturday, November 18, 2017

Limitorque Actuator Product Range

Limitorque has 90 years experience providing electric actuators to safely operate automated valves that protect people and property. The products that Limitorque offer are:
  • Intrusive Multi-Turn Actuators - L120 and SMB Series
  • Non-Intrusive Multi-Turn Actuators - MX Series
  • Non-Intrusive Quarter-Turn Electric Actuators - QX Series
  • Gas Powered Actuators - LDG Direct Gas Actuator
  • Hydraulic Actuators - LHS and LHH Series
  • Pneumatic Actuators - LPS and LPC Series
  • Multi-Turn Gearboxes - V Series and SR Series
  • Quarter-Turn Gearboxes - WG Series and HBC Series
For more information on Limitorque watch the video below and visit https://www.swansonflo.com or call 800-288-7926.

Thursday, August 17, 2017

A Proven Actuator Ideal for Valves Requiring Rotary or Linear Movement

Limitorque L120 electric actuator
Limitorque L120 electric actuator.
Whether used with gate valves, globe valves, penstocks or sluice gates, versatile Limitorque L120 Series actuators operate without modification in any rising or non-rising stem application for linear-action valves.

When combined with a Limitorque WG or HBC series quarter-turn gear operator, L120 actuators can also be used to control butterfly, ball and plug valves, as well as damper drives, flop gates or any other device which requires rotary movement.

L120 actuators are specified for use in petrochemical, power generation, and water and waste treatment applications where failure of a single actuator can be extremely costly … even catastrophic.

For more information on Limitorque actuators, visit Swanson Flo's website or call 800-288-7926.

For your convenience, below you will find the Limitorque L120-85 installation and operation manual.


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 http://www.swansonflo.com or call 800-288-7926.

Monday, March 27, 2017

Understanding Motor Operated Valves (MOV) in Industry

The video below demonstrates the operation a small (Worcester) motor operated ball valve (MOV). Also known as an “electric actuator”, motor operators come in a wide variety of sizes and styles. Some electric actuators are intended for quarter-turn valves (such as ball and butterfly valves), while others are designed to operate linear valves (such as gate and globe valves).

The MOV / electric actuator consists of an electric motor with the gearbox assembly which rotates the shaft of the valve. Most MOVs operate at 120, 240 or 480 volt, single or three phase. Basic features include adjustable limit switches to limit valve travel and to notify valve status, directional settings, analog inputs to allow for precise control, analog outputs to provide a feedback signal and digital communications. MOV enclosures can be either NEMA 4, NEMA 4X and NEMA 7 and are available in a wide range of torque outputs to match the valve it is operating.

Saturday, January 28, 2017

Electric Valve Actuators by Limitorque

Limitorque Actuators
Electric Actuator (courtesy of Limitorque)
Modern actuators are increasingly equipped with functions that provide information to the process operator, closing the loop with feedback that confirms the valve position, suitability of the energy supply to the actuator, and a range of other specialized data points.

A continuous goal for any plant is is a reduction in whatever level of maintenance that is currently required to keep everything operating. Maintenance is costly and time consuming, a set of many specialized tasks, each with a probability of not being completed properly.

Industrial process control encompasses a broad range of fluid handling operations. A significant part of fluid control is accomplished by valves, many of which are operated automatically through the use of actuators. Actuators are mounted on valves in place of, or in addition to, a hand-wheel, lever, or other manual means of opening and closing the valve. With an actuator installed, a control signal can be transmitted from a remote source to the actuator, commanding a change in valve position, and the actuator will respond by converting some form of connected energy into mechanical motion that positions the valve accordingly.

The Flowserve Limitorque L120 electric actuator pictured above is designed for a wide range of environmental applications in power, oil & gas, and water industries.

Visit Swanson Flo at www.swansonflo.com or call 800-288-7926 to find out more about Limitorque and discuss your potential applications.