Appeared in Steel Times International in the July/August 2016 issue
US-based Hunt Valve, a company with almost 100 years of experience in the field of fluid power engineering solutions, has introduced a new poppet valve for descaling applications that it claims will last three to five times longer than traditional poppet valves.
“By eliminating the effects of water hammer and system shock, this innovative poppet value technology promotes safety in the plant and cuts operating costs in half,” according to the company.
In a steel mill environment, persistent water hammer in high pressure piping systems often leads to burst pipes, cracked welds and descale header damage. Hunt Valve’s proportional poppet descale valve can be programmed to eliminate water hammer in the system. The company claims that speed is only reduced for the last 10-20% of the stroke, just before completely shutting off flow to the descale header. This slow rate of closure can be fine-tuned via the integrated local control interface or programmable logic controller (PLC).
“By replacing all fast-closing poppet valves in the descale system with Hunt Valve’s proportional poppet design and eliminating water hammer, companies save up to US$250,000 a year in replacement costs for damaged descale headers and pipes,” explained Tim Pulcini, Hunt Valve’s business development representative. “This helps
reduce annual plant operating costs for descale valves and piping by as much as 50% and decreases unexpected downtime.”
Extended service life
To combat the high-velocity fluid flow created by the valve’s slow rate of closure, the proportional poppet descale valve incorporates ceramic seating surfaces that prevent wear from the fluid flow. Optimizing the valve’s useful service life, the full ceramic seat is three to five times more durable than conventional seat materials such as heat-treated stainless steel. No other industrial valve manufacturer provides ceramic wear protection at this level, claims Hunt Valve.
The proportional poppet valve’s electromechanical linear actuator avoids the maintenance and reliability issues commonly associated with all types of media-actuated valves. Unlike traditional poppet valves that use dirty descale water as a hydraulic media to shift the main valve, the proportional poppet valve actuator is not a wetted part and is completely isolated from the descale water. Because it uses an electrical actuator, it eliminates the moisture and contamination problems associated with pneumatic actuation.
The proportional poppet descale valve is ideal for the OEM builder who wants to provide the highest level of customer satisfaction and avoid warranty issues after installation and start-up. However, if a failure occurs during this extended timeframe, it is covered. Because of the valve’s exceptional durability, Hunt Valve is able to offer an extended warranty, which allows the OEM to pass the benefit along to his or her customer. The extended warranty also assures aftermarket customers that the valve technology will deliver a significantly longer service life than traditional poppet valves, resulting in maintenance cost savings over the life of the valve.
The proportional poppet descale valve incorporates Hunt Valve’s patented balance chamber design feature. It offers proximity switches or linear variable differential transformer (LVDT) position feedback for constant monitoring of the valve’s position. The valve has a pressure rating of 5,000 psi (320 bar) and is available in sizes DIN 10 to 250 (0.5” to 10” in diameter). It is offered as a drop-in replacement for an existing valve without requiring any costly piping modifications to install the new valve.