This page contains links to many useful items including control valve related articles I have posted to the Web site of my former employer, Valin® Corporation. Valin is a multi location distributor of a broad range of equipment for fluid processes and factory automation. For more information about Valin, Click here. 

 

Some of these articles have also been published in trade magazines.

 

 Converting a Non-Linear Valve Installed Flow Characteristic to a Linear Flow vs. Controller Output

 This article was posted on the Valin Corporation web site in January 2018

In my book, Control Valve Application Technology (published and distributed by Valin Corporation), I explain how to properly size and select a control valve. I recently received inquiries from customers interested in a further explanation of one of the graphs featured in his book. This article will cover that explanation.  https://www.valin.com/resources/whitepapers/converting-non-linear-valve-installed-flow-characteristic-to-a-linear-flow-vs-Controller-Output

 

 Modern Tools for Sizing Control Valves and Actuators

This article was published in the January 2018 issue of Processing magazine.

https://www.valin.com/resources/articles/modern-tools-for-sizing-control-valves-and-actuators

Or download a PDF of the article by Clicking here

 

 To read the article on Liquid Flow in Control Valves that includes a discussion of choked flow, flashing and cavitation, including methods for predicting the potential for cavitation damage and for eliminating cavitation Click here. 

On 1/30/17 I updated the article to reflect the latest IEC/ISA terminology for the name of the dividing line between non-choked and choked flow. In the past this dividing point was unnamed in the Standards. In the current versions of the Standards it is named “DP_choked.”

To read the article on Gas Flow in Control Valves which includes a discussion of the factors that result in choked flow and that allow the ISA gas sizing equations to accurately predict the relationship between pressure drop and flow through a valve, Click here.

 

This link is to a short article Aerodynamic Noise in Control Valves that discusses how aerodynamic noise is generated. To read it, Click here.

 

This link is to Valve Aerodynamic Noise Reduction Strategies, which is a follow-up to the above article. The source control strategies are similar for cavitation control and hydrodynamic noise reduction. Note, however, that the “Path control” strategy for noise reduction is only applicable to aerodynamic noise. High hydrodynamic noise levels normally indicate the potential for rapid and severe valve damage and must be dealt with at the source. To read it, Click here.

 

This article on Control Valve Flow Characteristics explains the difference between a control valve's inherent and installed flow characteristic. To read it, Click here.

 

Perhaps the most misunderstood subject in the world of sizing control valves is Determining the Pressure Drop to be Used in a Control Valve Sizing Calculation. To read the article that discusses this subject Click here.

 

This article on Installed Gain as a Control Valve Sizing Criterion explains the meaning of installed gain, gives recommended installed gain criteria, and includes a demonstration of using the installed gain to select the best valve for a particular application. To read the article, Click here.

 

After a telephone conversation I had with the Editor of Valve magazine, she wrote an article titled Installed Gain and Control Valve Selection for the Web edition of Valve Magazine. To read the article, Click here.

Or to download a PDF of the article by Clicking here

 

In this Control Valve Q and A article published in Flow Control Magazine I answered a number of control valve related questions. To read the article, Click here.

Or download a PDF of the article by Clicking here

 

This article, An Insider’s Guide to The importance of selecting the right control valve inherent flow characteristic and selecting the right size valve was published in the February 2015 issue of Flow Control magazine. To read the article, Click here

Or download a PDF of the article by Clicking here

 

This article, An Insider’s Guide to Control Valves & Process Variability was published in the March 2015 issue of Flow Control magazine. To read the article, Click here

Or download a PDF of the article by Clicking here

 

This article, An Insider’s Guide to Installed Gain as a Control Valve Selection Criterion was published in the May 2015 issue of Flow Control magazine. To read the article, Click here

Or download a PDF of the article by Clicking here

 

This article, Keys to Effective Valve Sizing & Selection was published in the July 2015 issue of Flow Control magazine. To read the article, Click here

Or download a PDF of the article by Clicking here

 

New article as of 5-3-17

Determining Gas Density Using the NIST Chemistry WebBook

I recently posted an article on the Valin web site describing how to use the NIST Chemistry WebBook to accurately determine the density of a long list of gasses.

To read the article, click here

or copy and paste this link into your browser.

http://www.valin.com/resources/blog/determining-gas-density-using-nist-chemistry-webbook

 

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