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Publikation

Preview of the upcoming „Actuated Valve Assembly“ module in CONVAL®
27 August 2020

In June 2019, the recommended practice S2812-X-19 was published by WIB at Valve World Americas Conference. The RP (Recommended Practice) is called „Actuated Valve Assembly -A Recommended Practice for Part turn Automated On-Off valves“ and addresses the issue of the framework, including definitions, of the sizing and selection and mechanical integrity of the industry’s most common automated valve assemblies.
Since F.I.R.S.T. extensively supported the development of the RP both procedurally and with demonstrable prototypes, it is naturally obvious that a module in CONVAL® will soon be available that comprehensively maps the RP. This is procedurally further supported by the International Standards Organization (ISO) to accept the proposal and publish an ISO standard based on the RP.

How to solve the Actuated Valve (AV) Assembly Torque Requirement Puzzle?
03 December 2018

An article on the What, Why, How and the potential benefits to size & select Fit for the Application Actuated Valve Assemblies (Picture 1), called also Automated On/Off Valves, Emergency Shutdown Valves (ESDV), Blowdown Valves, Automated Block Valves, or other named valves within the process industry…

Catching unfit control valves
22 March 2017

How do you catch those unfit control valves during your project before it is too late? I mean too late before it really hurts! Before it eats your energy! Before it gives you sleepless nights! During my 42 years in the petrochemical industry, working 35 years for an American oil and gas major, I was often involved in large and mega projects as the automation engineer responsible for the engineering, commissioning and startup of instrumentation and control including those control valves.

Applying KPIs for valve reliability in projects with valve manufacturers, EPCs and end-users
13 January 2017

Large capital projects in plant engineering come along with special challenges. It’s not unusual that starting up a plant for the first time and get it operating reliable causes reengineering and replacement of critical control valves and may lead to startup delays and significant operation loss in the early beginning of its live cycle. Applying new principles of operation for “Non Process Quality Control” (NPQC) show the way to a signi- ficant increase of quality in valve selection and reduction of cost for the plant operators at a very attractive cost benefit ratio.

A new CAT on the NPQC scene!
27 May 2014

I am ready to introduce a new CAT on the NPQC scene, with focus on control valves! If you don’t know what I am talking about? Then please read on and let me explain.

Controllability Index: the effective CONVAL® approach to optimize your valve configuration
07 October 2009

Prediction of regulation quality has recently repeatedly been the subject of discussion and debates, and it can be assumed that a practical and objective application guideline for regulation quality, orientated around the end-user's needs, will be presented during the further course of this year. With a view to efficient determination of the optimum valve configuration during the initial phase of design and valve selection, a static regulation quality index has been unveiled and implemented in CONVAL® 8.0.

Optimized design and selection of valves using a controlability index
06 October 2009

Prediction of regulation quality has recently repeatedly been the subject of discussion and debates, and it can be assumed that a practical and objective application guideline for regulation quality, orientated around the end-user's needs, will be presented during the further course of this year. With a view to efficient determination of the optimum valve configuration during the initial phase of design and valve selection, a static regulation quality index has been unveiled and implemented in CONVAL® 8.0.

Nanhai revisited
31 January 2006

Interview with lead engineer for instrumentation and control Mr. Teun Hooftman.

The April 2005 issue of Valve World included an article looking at the 4000 control valves being specified for the massive Nanhai project in China. This follow-up article takes control a step further, looking at the 60-odd severe service control valves that have been specified.

The solutions were found with the help of CONVAL. 

Plant design and control valve selection under increasing cost and time pressure - Part II
31 May 2005

This is the second and final section of Mr Siemers´ technical paper addressing plant design and control valve selection when working under increased time and cost pressure. The first section (April issue) focused on control valve operating points and provided a case history involving a mismatch before introducing better valve sizing practices.

Part two starts by explaining the trends and definitions of inherent valve characteristics before focusing on “quick and dirty” sizing. The paper then addresses cavitation before concluding with the expert software available to help select the optimum valve characteristic form.

 

Plant design and control valve selection under increasing cost and time pressure - Part I
31 March 2005

Following a career spanning three decades, Mr Siemers is well aware of the pitfalls to be avoided when specifying control valves for a range of demanding applications.

In his latest paper for Valve World, he looks further into plant design and control valve selection when working under increased time and cost pressure. This article is split into two parts: broadly speaking, part one looks at control valve operating points and provides a case history involving a mismatch.

The author then introduces better valve sizing practices and uses this theory to resolve the problems introduced in the case history. Part two (scheduled for the June issue) starts by explaining the trends and definitions of inherent valve characteristics before focusing on „quick and dirty“ sizing.

The paper then addresses cavitation before concluding with the expert software CONVAL to help select the optimum valve characteristic form.

 

Control valve design aspects for critical applications in petrochemical plants – part III
30 September 2004

This final section of Mr Holger Siemers article on control valve design and sizing continues on from part I+II, which can be found in the June and August 2004 issue of Valve World.

 

Control valve design aspects for critical applications in petrochemical plants – part II
31 July 2004

This second section of Mr Holger Siemers article on control valve design and sizing continues on from part I, which can be found in the June 2004 issue of Valve World. This section presents information on design, size and use of severe service control valves, the kind of troubles that can be predicted with control valve sizing as well as suggestions for troubleshooting control valve failures. The final section, part III, will be ready and waiting in the upcoming October issue.

 

Control valve design aspects for critical applications in petrochemical plants – part I
31 May 2004

With three decades of experience in demanding applications, Mr Siemers has a deep appreciation of developments and trends in sizing control valves. In this paper, he reviews the past, present and future of valve design and sizing, taking all-important issues such as increasing cost pressure and time pressure into account. This paper is presented in two parts: firstly, how to use manufacturer independent software to analyze given or calculated plant parameters in more detail from an overall point of view with a complete power check and optimizing possibilities. Some case studies are also discussed. The second section, scheduled for a future issue, includes information on to design, size and use severe service control valves with good performance for long maintenance intervals. Different philosophies of valve design (plug design), pressure balance systems, stem sealing, actuator sizing, cost philosophies for “high end” applications are discussed.

 

Berechnung vom Dampfumformventilen mit CONVAL®
31 January 2002


Seit langem schon gibt es herstellerspezifische wie auch unabhängige Softwarelösungen, um verschiedenste Arten von Stellventilen auszulegen und zu optimieren.


CONVAL® hat bisher das Spektrum vom Hubventil über Klappen und Kugelhähne bis hin zum Membranventil mit allen nötigen Zusatzberechnungen abgedeckt.


Im kommenden Release 6.0 wird das Paket unter anderem auch durch Optionen zum Auslegen von Dampfumformventilen und dem dazugehörigen Einspritzventil erweitert.


 

Design of Control valves for gases with high differential pressures
28 February 2001

The fact that fluid properties are unknown and typical values for ideal gases are assumed by way of approximation frequently results in the over dimensioning of actuation systems for high differential pressure systems.

The isentropic exponent (kappa) and the valve factor xT can, in particular, have an enormous influence on the coefficient of flow Kv needed. The use of CONVAL® 5.0 software for design with integrated thermodynamic physical data computation and a valve database virtually eliminates such errors.

Process and energy management for control valves and pipe internals with CONVAL(r) 5.0 for Windows
08 September 1999

This article describes CONVAL® 5 for Windows, which was recently launched in the marketplace following a development phase lasting several years. It begins by demonstrating typical problems relating to time-critical plant design, focusing particularly on the plant and control valve parameter "dynamic pressure ratio" (dp100/dp0) and continuous valve characteristics between linear and equal-percentage. The CONVAL® software optimizes the interaction between the two sides of the plant, namely the "control equipment" and the "controlled system", end-to-end and accordingly also ensures the best achievable balance between investments in these two areas, enabling plant designers to take more appropriate account of the differential pressure requirements of their control valves in spite of mounting cost pressures. The article concludes by describing the complete design and optimization process for a plant section where the use of this non-proprietary tool has allowed energy costs to be cut by more than 50%, with only minimal time necessary for engineering.

Component calculations from A to Z
09 October 2000

Plant structures often contain a large number of components that have to be designed and calculated precisely. CONVAL® is a software package which is intended to simplify the work of plant operators and planners. Its potential range of applications is examined here with reference to a practical example.