How valves affect system efficiency

A common assumption is that the weakest point in any industrial system exists at the valves. This is not always the case. Depending on the selected pipe and fitting material, valve material and joining method, many valves can uphold the same performance standards as the rest of the piping system.It is a good engineering practice to identify the weakest component in any system when determining the total system pressure rating. Valves utilized in non-metallic systems must always be considered for pressure capabilities in particular, as they can vary by manufacturer.

When working with acidic and/or caustic solutions, increasing the life of a system is vital. Corrosion is the culprit of many system issues, causing premature repairs, costly downtime and even complete replacement. Each of these setbacks results in significant costs and is reason enough for engineers to pursue opportunities to increase system life.Materials that are susceptible to corrosion often experience it at joints. The more system components involved, including fittings and valves, the greater the chance of corrosion plaguing the system.Even if corrosion does not damage a system to the point of needing immediate repairs, it can harm the valves. 

Valves are especially susceptible to both corrosion and degradation of the valve seats. Corrosion creates debris and scale that can make valves more difficult to move, making systems less efficient, or cause significant safety concerns in the event of a failure.Electrochemical corrosion is a specific type of corrosion more often experienced at valves when the line is heat traced and the material is not corrosion resistant.To avoid unnecessary energy consumption costs, industrial systems must optimize fluid dynamics. One way to do this is to minimize pressure drop or head loss.To optimize efficiency and limit energy consumption, plants prefer a valve with a higher flow coefficient. 

Valve manufacturers provide valve flow coefficients for each product.On a macro level, pressure loss in valves is lower for most thermoplastics than metals. CPVC valves, specifically, disrupt the flow in industrial piping systems less than the valves used for metal systems, better maintaining flow rates and efficiency. A few reasons for this include metal’s susceptibility to corrosion, scaling, rust and other mechanisms that reduce pipe, fitting and valve interior smoothness.When it comes to pressure rating a system, the portion with the lowest pressure rating becomes the system’s limiting factor. Oftentimes a valve inserted into the line has the lowest pressure rating, making it the limiting factor to the overall pressure rating of the system.