Thursday, May 12, 2016

Severe Service and High Performance Valves - More Than Just Heavy Duty

cutaway view of severe service metal seated ball valve for industrial use
Cutaway view of metal seated
industrial ball valve
Courtesy Marwin Valve
Industrial process control applications can be associated with some very stringent and challenging performance requirements for the physical equipment and components that are part of the process chain. In fluid based operations, control valves can be a point of significant impact from extreme fluid conditions, requiring careful design and selection consideration to assure proper performance and safety levels are maintained in a predictable way.

Industrial valves that are intended for application at the extremes are generally referred to as severe service or high performance valves. While there are plenty of published and accepted standards for industrial valves, one does not exist to precisely define a severe service valve.

So, how do you know when to focus valve selection activities on severe service or high performance valves, as opposed to those rated for general purpose? There are a number of basic criteria that might point you in that direction:
  • Very extreme media or environmental temperature or pressure
  • High pressure drop operation that may cause cavitation
  • Rapid or extreme changes to inlet pressure
  • Certain types or amounts of solids contained in the fluid
Certainly, any of these criteria might be found in an application serviceable by a general purpose valve, but their presence should be an indicator that a closer assessment of the fluid conditions and commensurate valve requirements is in order. The key element for a process stakeholder is to recognize when conditions are in evidence that might overrun the capabilities of a general purpose valve, leading to premature failure in control performance or catastrophic failure that produces an unsafe condition. Once the possibility of a severe service condition is identified, a careful analysis of the possible operating conditions will reveal the performance requirements for the valve.

There are numerous manufacturers of severe service or high performance valves, each seeming to concentrate on a particular performance niche. Marwin Valve has their own entry in the class, a high performance ball valve intended for use with pressures up to 990 psi (69 bar) and temperatures approaching 1000 deg. F (538 deg. C). Specialty construction features for service in this range includes a 3-piece body, specialty alloys for body, stem, and ball, and graphite body seals and stem packing. Numerous options and variants are available to customize the valve build to suit a replacement or new installation.

You can always get more information or discuss your special requirements with a product application specialist. They have application experience and access to technical resources that can help with selecting the right valve components to meet your severe service applications.