# \#controlvalve **URL:** https://forumautomation.com/tag/controlvalve/3.md [Latest](https://forumautomation.com/latest.md) · [Categories](https://forumautomation.com/categories.md) · [Tags](https://forumautomation.com/tags.md) --- ## [How does an Electronic Positioner work in Control Valves?](https://forumautomation.com/t/how-does-an-electronic-positioner-work-in-control-valves/13153)
**Author:** [@Rabert](https://forumautomation.com/u/Rabert)\ **Replies:** 0\ **Last updated:** [April 11, 2025, 10:50am UTC](https://forumautomation.com/t/how-does-an-electronic-positioner-work-in-control-valves/13153 "2025-04-11T10:50:38Z")
How does an Electronic Positioner work in Control Valves? In industrial systems, precise fluid and gas flow control relies on the Electronic Positioner, which ensures accurate valve positioning based on control signals… --- ## [Control valve Leakage Classification](https://forumautomation.com/t/control-valve-leakage-classification/13144)
**Author:** [@Rabert](https://forumautomation.com/u/Rabert)\ **Replies:** 0\ **Last updated:** [April 7, 2025, 8:07am UTC](https://forumautomation.com/t/control-valve-leakage-classification/13144 "2025-04-07T08:07:11Z")
International standards for control valve leakage categorization include ANSI (American National Standards Institute)/FCI 70-2(Fluid Controls Institute) & IEC 60534-4. These standards classify leakage levels depending o… --- ## [What does ‘duty cycle’ mean for an idle speed control valve?](https://forumautomation.com/t/what-does-duty-cycle-mean-for-an-idle-speed-control-valve/12630)
**Author:** [@Rabert](https://forumautomation.com/u/Rabert)\ **Replies:** 0\ **Last updated:** [September 27, 2024, 10:20am UTC](https://forumautomation.com/t/what-does-duty-cycle-mean-for-an-idle-speed-control-valve/12630 "2024-09-27T10:20:58Z")
Duty Cycle of an Idle Speed Control Valve In the setting of an idle speed control valve, duty cycle is the ratio of the time the valve is open to the whole time of a single cycle. It is represented as a percentage o… --- ## [What is the control valve's transfer function?](https://forumautomation.com/t/what-is-the-control-valves-transfer-function/12616)
**Author:** [@Rabert](https://forumautomation.com/u/Rabert)\ **Replies:** 0\ **Last updated:** [September 24, 2024, 12:19pm UTC](https://forumautomation.com/t/what-is-the-control-valves-transfer-function/12616 "2024-09-24T12:19:51Z")
The transfer function for a control valve is a mathematical representation of the connection between the input signal (control action) & the output signal (flow rate or valve position). This relationship is essential… --- ## [How is Gland Packing used in Control Valves?](https://forumautomation.com/t/how-is-gland-packing-used-in-control-valves/12385)
**Author:** [@Rabert](https://forumautomation.com/u/Rabert)\ **Replies:** 0\ **Last updated:** [August 6, 2024, 5:10pm UTC](https://forumautomation.com/t/how-is-gland-packing-used-in-control-valves/12385 "2024-08-06T17:10:52Z")
In control valves, gland packing is applied chiefly in checking leakage of the controlled fluid round the valve stem. Here are some of the primary uses that explain why valve packing is used on control valves. Leak… --- ## [What is CV of a control valve ? Free excel tool to calculate Control valve CV](https://forumautomation.com/t/what-is-cv-of-a-control-valve-free-excel-tool-to-calculate-control-valve-cv/684)
**Author:** [@denizen](https://forumautomation.com/u/denizen)\ **Replies:** 1\ **Last updated:** [August 5, 2024, 1:38pm UTC](https://forumautomation.com/t/what-is-cv-of-a-control-valve-free-excel-tool-to-calculate-control-valve-cv/684 "2024-08-05T13:38:16Z")
What is a CV? CV is a flow coefficient which is really specking to the capacity of a valve. If a valve has a CV of 20 that means we can pass 20 gallons of water per minute with one pound pressure drop. CV is a measure… --- ## [Control valve symbols in P&id](https://forumautomation.com/t/control-valve-symbols-in-p-id/10897)
**Author:** [@Instrument\_Engineer](https://forumautomation.com/u/Instrument_Engineer)\ **Replies:** 0\ **Last updated:** [February 22, 2023, 6:02am UTC](https://forumautomation.com/t/control-valve-symbols-in-p-id/10897 "2023-02-22T06:02:44Z")
Control valves are used in process control systems to regulate the flow of fluid, gas or steam. These symbols are used in process flow diagrams, P&IDs (piping and instrumentation diagrams), and other engineering draw… --- ## [Types of Valves](https://forumautomation.com/t/types-of-valves/10894)
**Author:** [@Sudha\_m](https://forumautomation.com/u/Sudha_m)\ **Replies:** 0\ **Last updated:** [February 20, 2023, 6:08pm UTC](https://forumautomation.com/t/types-of-valves/10894 "2023-02-20T18:08:20Z")
Different types of Valves Valves are mechanical devices that open, close, or partially obstruct various paths in order to regulate, control, or direct the flow of fluids (liquids, gases, or slurries). There different… --- ## [Asking for spare part list of rotork control valve](https://forumautomation.com/t/asking-for-spare-part-list-of-rotork-control-valve/10121)
**Author:** [@Saba\_Sanami](https://forumautomation.com/u/Saba_Sanami)\ **Replies:** 0\ **Last updated:** [January 12, 2022, 5:46am UTC](https://forumautomation.com/t/asking-for-spare-part-list-of-rotork-control-valve/10121 "2022-01-12T05:46:07Z")
Hello I am writing to ask for spare part list of two model of rotork control valves including SI1-L200/65-161-11-04AB and SI2-2.1-L250/105-161-11-04AB. I highly appreciate if any one could provide me with these two lists… --- ## [PID Tuner : A free PID tuning tool](https://forumautomation.com/t/pid-tuner-a-free-pid-tuning-tool/9720)
**Author:** [@pidtuner](https://forumautomation.com/u/pidtuner)\ **Replies:** 0\ **Last updated:** [August 10, 2021, 8:52am UTC](https://forumautomation.com/t/pid-tuner-a-free-pid-tuning-tool/9720 "2021-08-10T08:52:27Z")
Take into account these tips for using it: --- ## [Control valve interview question and answers](https://forumautomation.com/t/control-valve-interview-question-and-answers/2540)
**Author:** [@sivaranjith](https://forumautomation.com/u/sivaranjith)\ **Replies:** 0\ **Last updated:** [October 30, 2017, 9:02pm UTC](https://forumautomation.com/t/control-valve-interview-question-and-answers/2540 "2017-10-30T21:02:49Z")
What is a valve? A valve is a device used to control the flow of fluid in a stream. What is a control valve ? A control valve changes the flow rate in the stream as a response to the controller output to change the ma… --- ## [Definition of "Pressure Sample Type Internal, back pressure"](https://forumautomation.com/t/definition-of-pressure-sample-type-internal-back-pressure/2732)
**Author:** [@Qulu\_Quliyev](https://forumautomation.com/u/Qulu_Quliyev)\ **Replies:** 0\ **Last updated:** [November 28, 2017, 6:35am UTC](https://forumautomation.com/t/definition-of-pressure-sample-type-internal-back-pressure/2732 "2017-11-28T06:35:49Z")
Dear All, I found the following definition in the valve datasheet “Pressure Sample Type Internal, back pressure”, but I don’t have clear idea what does it mean. Is there anyone who has clear explanation about it? Best Re… --- ## [What are the Important interview queations about Control valve?](https://forumautomation.com/t/what-are-the-important-interview-queations-about-control-valve/2403)
**Author:** [@sivaranjith](https://forumautomation.com/u/sivaranjith)\ **Replies:** 0\ **Last updated:** [October 7, 2017, 1:28pm UTC](https://forumautomation.com/t/what-are-the-important-interview-queations-about-control-valve/2403 "2017-10-07T13:28:19Z")
What is a control valve? A control valve is a final control element used to control fluid flow by varying the size of fluid passage in response to the signals received from controllers. Control valves are used to contro… --- ## [How to decide control valve body material ? (WCC or WBB)](https://forumautomation.com/t/how-to-decide-control-valve-body-material-wcc-or-wbb/1324)
**Author:** [@denizen](https://forumautomation.com/u/denizen)\ **Replies:** 0\ **Last updated:** [September 4, 2016, 6:52am UTC](https://forumautomation.com/t/how-to-decide-control-valve-body-material-wcc-or-wbb/1324 "2016-09-04T06:52:46Z")
The different of WCA,WCB and WCC is made of different steel grade. C is better than B, B better than A. all there had different temperature and strength rating. As for valve body selection (according to ISA) “Control va… --- ## [How to download articles,Quick start guide,ebooks and white papers about Fisher valves and regulators from emerson process management website?](https://forumautomation.com/t/how-to-download-articles-quick-start-guide-ebooks-and-white-papers-about-fisher-valves-and-regulators-from-emerson-process-management-website/1284)
**Author:** [@denizen](https://forumautomation.com/u/denizen)\ **Replies:** 0\ **Last updated:** [August 28, 2016, 12:38am UTC](https://forumautomation.com/t/how-to-download-articles-quick-start-guide-ebooks-and-white-papers-about-fisher-valves-and-regulators-from-emerson-process-management-website/1284 "2016-08-28T00:38:23Z")
Following documents about Fisher valve and regulators are available for free public download from the emerson website. Articles,white papers,Handbook about control valves,ebook,Brochures,Instruction manuals,Quick start … --- ## [What is leakage class rating (Valve Design)?](https://forumautomation.com/t/what-is-leakage-class-rating-valve-design/1283)
**Author:** [@denizen](https://forumautomation.com/u/denizen)\ **Replies:** 0\ **Last updated:** [August 28, 2016, 12:22am UTC](https://forumautomation.com/t/what-is-leakage-class-rating-valve-design/1283 "2016-08-28T00:22:35Z")
There are 6 leakage classes. Most common are class 4 and Class 6. Class 4 is intended for single ported,metal to metal seats.Leakage rate is limited to 0.01 of rated valve flow capacity. Class 6 is intended for resili… --- ## [Free tool for Control Valve CV calculation (Microsoft Excel tool )](https://forumautomation.com/t/free-tool-for-control-valve-cv-calculation-microsoft-excel-tool/849)
**Author:** [@denizen](https://forumautomation.com/u/denizen)\ **Replies:** 0\ **Last updated:** [March 12, 2016, 5:51pm UTC](https://forumautomation.com/t/free-tool-for-control-valve-cv-calculation-microsoft-excel-tool/849 "2016-03-12T17:51:45Z")
Control Valve CV calculation tool. CV calculation tool is made with Excel .It is absolutely free. Various CV calculations tools are available for download. What is Control Valve CV? The flowrate in gallons per minute …