- Published on Monday, 20 May 2013 12:12
- Written by Joanna Button
Valve Repair Activities per ASME Section I & B31.1
If you have valves in your plant manufactured from F-91 or C12A material you may have problems and need repair services. In a 2-year period at our valve service company, a number of valuable observations were made about the cause of repairs necessitated by defects or operation, and the most effective solutions.
- Published on Monday, 22 April 2013 11:29
- Written by Mark Buzzell
The ability to prevent unexpected shutdowns and maintain control valve performance is directly linked to profitability. The ARC Advisory Group estimates that the average cost of plant downtime is $12,500 per hour with some plants. For some, of course, that rate is significantly higher, running upwards of $1 million per day of downtime.
- Published on Tuesday, 16 April 2013 09:41
- Written by Alyssa Canales and James L. Browne
Oil wells drilled in deep waters typically face many difficulties with pressure, especially as the wells are placed on the bottom of the ocean floor. Oil and gas recovered from this depth can see pressures ranging 5,000 PSIG to 30,000 PSIG and possibly higher when flowing out of the well into the riser pipes. This is where many of the problems begin, and is the inspiration for development of valve technology that can withstand these extremely high pressures.
- Published on Thursday, 28 February 2013 10:17
- Written by Kate Kunkel
“No matter how big and complex the machinery gets," said John Gans during his presentation at the November 2012 Valve Repair Council Repair Meeting & Exhibition in Houston, "at its heart, holding everything together, is the humble little bolt."
Dr. Gans repeatedly stressed the importance of having well-trained personnel conducting the critical function of bolting, and provided a comprehensive overview of material normally provided in a full one-day course.
- Published on Wednesday, 06 February 2013 08:51
- Written by Kate Kunkel
Jon F. Monsen, Ph.D., P.E., is a control valve technology specialist, with more than 30 years' experience. He has lectured nationally and internationally on the subjects of control valve application and sizing, and is the author of the chapter on "Computerized Control Valve Sizing" in the ISA Practical Guides book on Control Valves.
- Published on Tuesday, 29 January 2013 14:21
- Written by Daniel Baran
To maximize machine operation and business results, engineers ought to consider more than how a servo valve performs with regard to flow/pressure gain, frequency response, and precision. The servo valve, in part, consists of a torque motor, flapper, spool and feedback mechanism. The feedback mechanism can last well above 1 billion cycles. But this lifespan is only achievable with the right selection of materials, manufacturing techniques and mechanical designs.
- Published on Friday, 10 August 2012 11:56
- Written by Chuck Reames
A motor-operated valve (MOV) stem nut typically is made of a bronze alloy material. During a period of time, stem nut threads wear from opening and closing the valve. Since the valve stem is made of stainless or carbon steel, thread wear typically occurs on stem nut threads.
- Published on Friday, 13 July 2012 16:11
- Written by Walter Moquin
With an estimated 60% of fugitive emissions attributed to valves it is easy to see EPA’s attention is on valve emissions reduction. Traditionally valve stem leakage was a visible event. Improvements in packing materials and design lead to non-visibly leaking valves.
In today’s world, government regulations drive measurement of valve leakage to the molecular level in parts per million (ppm). These extremely low vaporous emissions required packing manufacturers to evaluate their product performance to the latest EPA standards for Low E Valve Packing Technology.
- Published on Thursday, 22 September 2011 13:26
- Written by Peter Cleaveland
Coatings protect valves and actuators against wear, erosion, chemical attack and other forces that threaten their durability and effectiveness. But because they are faced with such a diversity of challenges, there are a broad number of differences in the types of coatings used. The coatings used for ball valves have their own set of characteristics that differ in many cases from other types of valves.
- Published on Wednesday, 19 January 2011 23:07
- Written by Brandon Parker and Bill Breitmayer
When considering the electric actuation industry, several topics are subject to conversation and analysis, including non-intrusive electric actuators and their overall capabilities and construction. Alternative discussion revolves around the evaluation of diagnostics and maintenance information available through (or in support of) Computerized Maintenance Management Software (CMMS), Asset Management Systems (AMS), Field Device Tools (FDT), Device Type Managers (DTM), Electronic Device Description Language (EDDL), and many other acronyms that make up the “alphabet soup” of the industry. However, regardless of what’s under discussion, one fundamental topic must be addressed adequately before truly considering data evaluation and data management—this topic is data acquisition (networking).
- Published on Tuesday, 01 June 2010 11:53
- Written by Peter Cleaveland
It’s time to do maintenance on a section of process. You don't want to shut down the entire facility, so you decide to block off and depressurize just the section you're working on. Just upstream is a double block and bleed valve—a trunnion-mounted ball valve with self-relieving seals and a bleed valve to vent the cavity. You close the ball valve and open the bleeder. Now you can de-pressurize the line downstream and open it up to work on it.