- Published on Monday, 08 December 2014 12:47
- Written by Greg Johnson
Valve components, such as bodies, bonnets and caps, are manufactured either by forging or casting. The forging process produces a homogeneous structure often needed for challenges such as specialized high-integrity applications. But it is much costlier than casting for large pieces. Because of this, although forged valve ranges go up to sizes NPS 4 and more, the vast majority of valves are comprised of cast pressure-containing components.
- Published on Tuesday, 16 September 2014 11:23
- Written by Mike Pemberton
Have you ever experienced a sprained ankle that tweaked your hip joint and then resulted in a stiff back? This is an illustration of how chain reactions can occur in complex systems. The body, like a highly engineered industrial process, can experience immobilization and downtime, i.e., each joint, bone and associated connective tissue inside works as part of a highly integrated system. When one subsystem fails, other issues may be the root cause.
- Published on Tuesday, 08 July 2014 07:43
- Written by Christian Dow
Today’s petrochemical and process industries increasingly depend on higher levels of automation, which in turn require enhanced monitoring and control of valve position and operational readiness. In the past, many valves were deployed without any monitoring devices; however, today’s processes require feedback not only for valve position monitoring but also for remote or automated control of valve actuators. In addition to new valves with feedback installed on projects, existing valves are being retrofitted with feedback devices or upgraded with more modern feedback technology. One of those is Magnetostrictive Linear Displacement Transducers (MLDTs).
- Published on Monday, 30 September 2013 09:06
- Written by David W. Spitzer
There are many types of flow devices used to measure liquids and gases in closed pipes and open channels. Knowing which flowmeter is appropriate for which application requires knowing the difference between the many choices. This column seeks to give readers a basic understanding of the different types of flowmeters and what to consider when selecting them.
- Published on Thursday, 20 June 2013 09:41
- Written by Leo Minervini
Plant operators across the world are tasked with maximizing efficiency and output from existing facilities, which can be a major challenge when there are many valves and actuators. Plant management strategy to accomplish this task includes developing a better understanding of how valve and control assets perform in the field and to adopt preventative maintenance to minimize plant downtime. Valve positioner technology today has evolved to help plant managers with this major challenge.