Friday, March 27, 2020

Glossary of Valve Terms and Acronyms

Glossary of Valve TermsTerminology plays a critical role in the understanding of specialized or technical contexts. Understanding the specific terminological meaning of the technical contexts in process control and industrial systems assists in defining and communicating the main message of a document, which in turn allows stakeholders the ability to transmit the content much more effectively.

A glossary is an alphabetical list of terms in a particular domain of knowledge with the definitions for those terms. It's purpose is to document the key words and phrases which are regularly contained in a body of content.

Val-Matic, a leading manufacturer of check valves, quarter turn shut-off valves and air valves for water/wastewater, industrial and building markets, has assembled an outstanding glossary of terms and acronyms used in the valve, process flow, and process piping segments. This is a must-have resource for anyone new in in industrial engineering, maintenance, or procurement.

You can download the Val-Matic Glossary of Valve Terms and Acronyms from this Automatic Controls of Virginia web page.

Sunday, March 22, 2020

Coronavirus Statement and Update


We at Automatic Controls of Virginia continue to navigate the ever changing COVID-19 pandemic. We are closely monitoring and following the guidance available through the Centers for Disease Control (CDC), the World Health Organization (WHO) and state and regional public health authorities. We are committed to keeping the safety of our customers, business partners, and employees.

Our Ashland warehouse location remains open and our supply chain remains intact. We are maintaining a limited staff in our Ashland Office to support critical functions including shipping/receiving, accounting, and IT.

Additionally, we have implemented the following requirements:

  • Restricting visitor access to our facility.
  • Increased frequency of sanitizing facilities and work spaces
  • Requiring regular hand washing and sanitizing.
  • Using technology where possible to replace in-person meetings.

We will update this statement as the situation changes.

We thank you for your continued business and support. Please stay safe and be well.

Thursday, February 27, 2020

Cavitation in Valves

Cavitation in Valves

Cavitation can occur in valves when used in throttling or modulating service. Cavitation is the
sudden vaporization and violent condensation of a liquid downstream of the valve due to localized low pressure zones. When flow passes through a throttled valve, a localized low pressure zone forms immediately downstream of the valve. If the localized pressure falls below the vapor pressure of the fluid, the liquid vaporizes (boils) and forms a vapor pocket. As the vapor bubbles flow downstream, the pressure recovers, and the bubbles violently implode causing a popping or rumbling sound similar to tumbling rocks in a pipe. The sound of cavitation in a pipeline is unmistakable. The condensation of the bubbles not only produces a ringing sound, but also creates localized stresses in the pipe walls and valve body that can cause severe pitting.
Cavitation

Read this white paper, courtesy of Val-Matic, to fully understand what happens when cavitation occurs in valves.

Table of Contents
  • Introduction
  • Cavitation Analysis
  • Cavitation Data
  • Valve Coefficient Data
  • Example Application
  • Conclusion & Recommendations
  • References
For question about the proper applications of valves, contact Automatic Controls of Virginia. Call them at (804) 752-1000 or visit their web site at https://acva.com.

Thursday, February 13, 2020

Basics of Industrial Valves and Actuators


This video provides a basic understanding of industrial valves types, and also an understanding of valve actuator types.

Industrial valves are designed in three major categories. They are:
  • Rotary multi-turn valves. These include gate, globe knife and multi port valves. 
  • Rotary quarter turn valves these include butterfly ball plug and choke valves.
  • Linear valves. These include gate, angle globe, and globe valves. 
There are many varieties and subcategories for these basic three design configurations.

Two major functions of industrial valves are isolation and control. Isolation valves are used in applications where the primary concern is the opening or closing of the valve when needed. Isolation valves provide tight shut off and sometimes provide simple control. They are operated via hand wheels or levers, electric actuators, pneumatic actuators, or hydraulic actuators.

Control valves are used to modulate flow to maintain a certain set point in the process control loop. Traditionally, control valves use pneumatic diaphragm positioners, but newer technology enables control with pneumatic and electric actuators.

There are three types of valve actuators:
  • Electric
  • Pneumatic
  • Hydraulic 
Electric actuators use electricity is their power source, have a relatively slow strokes speed, are moderately priced, and typically include the valve operating system. Electrical and mechanical technical skills are required to install and maintain electric actuators.

Pneumatic actuators use air or gas as their power source, have relatively fast stroke speeds, are relatively inexpensive, and require external devices for their valve operating system. In most cases, only mechanical technical skills are required to install and maintain pneumatic actuators.

Hydraulic actuators use hydraulic fluids as their power source, have fast stroke speeds, are more expensive, and require external devices for their valve operating system. Electrical and mechanical technical skills are required to install and maintain hydraulic actuators.

For more information about industrial or municipal valves, actuators or control systems, contact Automatic Controls of Virginia. They can be reached by calling 804-752-1000 or visit their website of https://acva.com.

Monday, January 20, 2020

Pinch Valves: An Outstanding Choice for Erosive and Abrasive Flow Conditions

Pinch Valves

Pinch valves are designed and constructed to outlast other types of valves in high wear applications. They are ideal where shut-off and control applications involve abrasive or corrosive slurries, powders or coarse substances.


PINCH VALVE OPERATION

In the open position, the valve is full bore with no flow restrictions. During closing, two pinch bars squeeze the valve sleeve shut on the centerline. Bubble tight shut-off is provided even if solids have built up on the sleeve wall. The rubber sleeve is the only wearing part which significantly reduces maintenance costs and extends service
intervals.

Pinch Valve OperationPinch valves can be either shut off valves (also known as isolation valves) or control valves, and provide superior performance in the most demanding applications, where conventional valves encounter problems with wear due to increased turbulence. When the controlled flow is abrasive, it is a big advantage to have only one, wear resistant, valve part in contact with the medium. Because of this, the need for maintenance and spare parts is greatly reduced.

As the valves are self-cleaning, even if any solids are accumulated in the sleeve wall, it breaks away when the valve is operated. This is due to the flexibility of the sleeve, making the valve lifetime longer than many other competing products on the market. The sleeve is naturally wear resistant and when particles hit the sleeve’s rubber surface, the energy is absorbed and released when the rubber bounces back.
Pinch Valve Advantages

Strongly consider the use of a pinch valve to retrofit or replace the failing ball, butterfly, or gate valve in your application. Most plant maintenance and engineering staff will tell you they are very pleased with the decision.

For more information on the many uses and applications of pinch valves, contact Automatic Controls of Virginia. They can be reached by calling (804) 752-1000 or visit their web site at https://acva.com.

Monday, December 23, 2019

Happy Holidays from Automatic Controls of Virginia


"This is my wish for you: peace of mind, prosperity through the year, happiness that multiplies, health for you and yours, fun around every corner, energy to chase your dreams, joy to fill your holidays!"  D.M. Dellinger