The latest standards development work carried out under the UK National Flow Programme has updated ISO guidance on the effects of pulsation of the process stream on flow measurement instruments.
“The new standard tells you how to take pulsations into account in calculations,” explains Principal Consultant, Dr Michael Reader-Harris. “This is something that no other flow standards tells you how to do.”
The new standard is ISO/TR 3313:2018. It provides a definition of pulsating flow and indicates how to detect it. It has broad applicability and describes the effects of pulsating flow on orifice plates, nozzles or Venturi tubes, turbine and vortex flowmeters. These flowmeters are amongst the types that are most susceptible to pulsation effects.
“The work was a revision of the existing standard, but not a normal revision,” Michael explains. “The original standard was twenty years old and ISO said that it was no longer in an acceptable form. We decided to re-instate the standard, as the information it contained was in danger of being lost, and to make it good for the next twenty years.”
According to Michael the standard is vitally important because it enables people to improve the measurement of pulsating flows, which are found in many real-world situations.
Michael’s work, which took place over the last two years, was all desk-based, with BSI editors making a significant contribution. All the original standard’s equations were reviewed and checked, inaccuracies were addressed and the standard’s equations were reformatted into a modern style.
“It was a significant piece of work,” Michael says. “We had to recover information from twenty years ago. We couldn’t repeat the research that had been carried out for the original standard as the test rigs no longer exists and many of the people involved with the original research had retired.”
For more details, contact Michael Reader-Harris.
Wednesday, April 04, 2018