Friday, December 11, 2015

Severe Service Valves - More Than Just Heavy Duty

Three industrial valves for severe service
Severe Service Industrial Control Valves
Courtesy Flowserve - Kammer
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, the control valves can be a point of significant impact of 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 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 valves, as opposed to general purpose valves?
There are a number of basic criteria that might point you in that direction:

  • Very extreme media or environmental temperature
  • High pressure drop operation that may cause cavitation
  • Rapid and 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 valves, each seeming to concentrate on a particular niche. Kammer, a brand in the Flowserve family, has an interesting approach to accommodating the highly varied requirements of severe service applications. Their product line consists of a number of standard configurations, but also includes semi-modular components that can be combined to meet the many custom requirements of severe service applications.

I have included a technical bulletin (you know it's technical when it's not in color) that describes and nicely illustrates how the company employs various interchangeable body styles and packings with their multi-stage plug to meet a wide range of severe service challenges. Browse the bulletin, as it has some good cutaway views of valve interiors. 

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