What to Look for in Control Valve Technology to Positively Impact Your Bottom Line

Emerson's Vincenzo Sipala


Author: Vincenzo Sipala

How Plant Downtime Effects Your Bottom Line

Due to improper control valve selection, the valve trim pictured above was damaged by solids from the fluid, which was originally specified as clean.

Keeping an intricate process plant at maximum productivity for multiple decades is no easy feat. Operations downtime caused by unscheduled maintenance issues continues to be a major cause of concern for companies, as it can have expensive consequences. According to Solomon Associates, companies reach the Top Quartile performance when they have less than three percent unplanned downtime and maintenance costs less than two percent of plant replacement value (PRV). For 24/7 industries, users have the potential to cut maintenance spend by 50 percent or more simply by reducing downtime.

An unexpected loss of plant uptime means a reduction in revenue, throughput, and capacity utilisation. Restarts and shutdowns also consume additional energy and increase energy intensity with the potential for unwanted emissions and safety incidents. These adverse side effects impact the bottom line. But selecting the right measurement and control products for each application can be the key to significant savings.

Which Technology Needs Careful Selection?

Technologies that play a critical role in plant operations require special attention when evaluating purchasing options. Wireless technology, for example, impacts plant uptime, as it enables additional measurement devices to be installed quickly and easily, providing data needed to help optimize process control and increase operational efficiency. Selecting the right wireless devices can:

  • help operators gauge equipment health and proactively identify potential problems
  • help operators schedule maintenance
  • reduce installation and configuration time
  • reduce costs by 30 percent or more compared to a wired solution
  • provide flexibility for repositioning instruments without complicated rewiring.

Another component that can impact plant operations is control valves, which represent a significant capital investment for many refineries and play a vital role in plant safety and optimization. Industries have historically replaced perfectly functioning control valves during planned shutdowns because valve health data was unavailable. However, smart valve technology allows technicians to monitor control valve health and support predictive maintenance, reducing the chance of an unplanned shutdown. Careful selection of control valves can help minimize or avoid:

  • Cavitation – when a liquid is subjected to rapid changes of pressure, it causes bubbles that generate shock waves. These waves decrease flow capability and cause material damage, and excessive noise and vibration.
  • Noise – high noise levels place plant workers at risk, are a nuisance to surrounding communities, and lead to equipment damage, control issues, and potential unplanned shutdowns.
  • Compressor surge – occurs when the amount of gas is insufficient for the speed of the compressor. Proper selection of anti-surge valves can increase the life of compressors and plant reliability.

Examples of Proper Control Valve Selection

A refinery in Singapore was receiving complaints of excessive noise from surrounding communities due to an unsuitable steam vent valve and silencer system. When tasked with reducing the noise levels to 76 dBA or less, plant personnel upgraded their existing control valves and silencer with proper anti-noise solutions which reduced the noise to the required level.

At a gasification power plant in Italy, grey water – which has corrosive and erosive properties – produced during the gasification process was stunting the existing control valves’ lifecycle to no more than two weeks. This caused a big reduction in plant reliability, with shutdowns taking place every fortnight. The solution was a special valve able to manage high pressure drop and unclean fluids simultaneously, solving the customer needs and increasing maintenance intervals.

Conclusion

Whether you have a multibillion-dollar plant with thousands of control valves or a smaller operation, selecting the right technology can help improve your bottom line. Common process upsets caused by inefficient control valves can negatively impact production uptime, increasing operational costs and the chances of a safety incident. Whether it is severe service applications for power, hydrocarbon, chemical or pulp and paper industries, control valves can have a significant impact on plant performance, and therefore on a company’s bottom line. It is vital that sound solutions are provided by technical experts to address critical applications for aerodynamic noise, cavitation and out-gassing issues, as well as particulate erosion.

From Jim: Vincenzo will be speaking at the Valve World Expo in Düsseldorf, Germany. You can attend his presentation on control valve selection today, Nov. 28 at 15.30 in room 1 if you are there at the conference.

You can also connect with more valve experts in the Valves, Actuators & Regulators group in the Emerson Exchange 365 community.

Posted Wednesday, November 28th, 2018 under Final Control Element.