Aftermarket Service + Parts

Magnum® HammerHead™ Valve Nails It

Specifically designed for high molecular weight applications at both low and high compressor speeds.

Like the heart is to the human body, valves are critical to compressor performance.

Above and beyond a new addition to our valve portfolio, the highly efficient and reliable Magnum® HammerHead™ valve is specifically designed for high molecular weight applications at both low and high compressor speeds. It has already proven itself in nearly two dozen different applications to solve clients’ challenges.

The Magnum HammerHead valve can be applied to all brands of reciprocating compressors. Many clients are already benefiting from improved valve reliability and compressor efficiencies by upgrading to the Magnum HammerHead valve in carbon dioxide, ethylene, propane, and natural gas services.

For example, one client with several Dresser-Rand HHE-VL compressors on CO2 service wanted to reduce power consumption without losing capacity. The client agreed to have the Magnum HammerHead valves installed in one of the HHE-VL compressors on a trial basis to see how they performed. A competitor’s valves were removed from this “test compressor” and replaced  with Magnum HammerHead valves. The other HHE-VL units were still using the competitor’s valves and operating at the same conditions, so this enabled a head-to-head comparison. A third party was hired to evaluate compressor operation and take field test measurements. Results were immediately evident in the compressor fitted with the Magnum HammerHead valves — the motor drew less current, equating to approximately 10% lower power consumption and compressor flow increased. This “test compressor” has been in continuous service since October 2012 and the client has since outfitted the other HHEVL compressors at this facility with Magnum HammerHead valves.

HammerHead67-003The Technology Behind the Valve

Computational fluid dynamics (CFD) and finite element analysis (FEA) were used to develop the HammerHead valve’s geometry which improves valve flow area by as much as 60 percent compared to standard Magnum® valves. Minimal valve losses translate into improved compressor efficiency. Flow testing revealed that the Magnum HammerHead valve surpassed all other valve types tested including the poppet, plate and ring-type valves.

Unlike other poppet valves, the HammerHead valve can be applied at high compressor speeds. The HammerHead valve’s unique element design minimizes tensile stresses. The streamlined flow path with optimized seat, guard and lift areas, maximizes valve flow area and is more tolerant of particles and liquids in the gas. Further, one element is used for all valve sizes which simplifies inventory management, minimizes replacement costs and increases interchangeability.

The precision-guided element and springs increase the reliability of moving parts for long-term operation. The proven valve element geometry reduces fatigue stresses for extended life while minimizing power losses. The result: long life in some of the most demanding applications.

Field Proven Results

In another example, a client was experiencing higher-than-expected discharge temperatures on its 7-inch stroke Dresser-Rand HOS™ high-speed reciprocating compressor in CO2 service. This low-inlet pressure CO2 service began reaching high temperature alarm set points during the hotter summer months. After replacing the HOS compressor’s valves with the Magnum HammerHead valves, discharge temperatures dropped 15 F (-9.4 C) and allowed a safe margin below the alarm set points. Achieving a 15 F (-9.4 C) reduction in discharge temperatures was attributed to the Magnum HammerHead valve’s improved flow area and resulting high efficiency. The highstrength valve element allows operation at high compressor speeds and pressure differentials.

In another high-speed compressor example, history was made with the application of the Magnum HammerHead valve design in a Dresser-Rand valvein-piston model D (D-VIP®) compressor. The client was suffering premature damping plate failures in its 1,200 RPM natural gas D-VIP compressors.

After extensive finite element analysis and valve motion simulations, a VIP version of the Magnum HammerHead valve was developed, and for the first time ever a “poppet” style valve was used in a VIP compressor. The solution involved a direct drop-in replacement of all the inlet and discharge valves. What made this possible? The unique design features of the HammerHead elements keep stresses low and efficiency high. To date, the Magnum HammerHead valves have run two to three times longer than the plate valves. The client awarded Dresser-Rand a multi-year service contract and ordered Magnum HammerHead valves for its other three D-VIP compressors.

In the year and a half the Magnum HammerHead valve has been on the market, it has already demonstrated a high level of versatility by operating well in clean gases, dirty gases, gases with entrained liquids, and gases with high molecular weights. It is adaptable enough to be used with any type of unloading device, including finger unloaders, plug unloaders and port unloaders, and is one of the few valves available today that is flexible enough to be applied to both high- and low-speed reciprocating compressors.

Tags: Magnum Valves, Reciprocating Compressor Valves

other articles from insights issue Spring / Summer 2014