FOX AS – ASS Series Bladder Accumulator – Small Volume
The FOX AS – ASS Series Bladder Accumulator – Small Volume represents a high-level engineering solution for hydraulic energy management, volume loss compensation, and pulsation dampening in hydraulic circuits. The range is divided into three main series, each designed to meet specific operating requirements: the international HB series (bottom-repairable), the HBX stainless steel series, and the ACSX series, also manufactured in stainless steel. Every model ensures strict tolerances and optimized mechanics, making these accumulators indispensable in industrial and process applications requiring absolute reliability and precise fluid dynamic control.
Construction Features and Materials Used
The durability of the FOX AS – ASS Series Bladder Accumulator – Small Volume derives directly from the materials selected for both the body and sealing components. The HB series features a forged steel body, carefully sandblasted and painted to withstand mechanical and environmental wear. Alternatively, it is available with dedicated internal coatings and epoxy external painting according to standard procedures or specific project requirements. The HBX and ACSX variants are entirely manufactured in AISI 316L stainless steel, ensuring exceptional corrosion resistance and making them ideal for chemically aggressive environments or offshore applications.
Bladder and Fluid Specifications
The operational core of the component is the hydro-pneumatic separation bladder. In the standard configuration, the bladder is compatible with mineral oils and non-aggressive fluids, guaranteeing operating temperatures for the HB series ranging from -20°C to +80°C. To expand the field of application, the bladders are available in several high-performance compounds, including HNBR, EPDM, FPM, HYTREL, Butyl, and Polyurethane. This construction versatility allows engineers to select the ideal elastomer according to the chemical nature of the working fluid and the operating temperatures required by the system.
Operating Pressures and Working Principle
The pressure levels supported confirm the high technical standards of the device. The HB series supports a maximum working pressure (PS) of up to 350, 480, or 690 bar in special versions. The HBX series manages operating pressures from 50 to 450 bar, while the ACSX series is rated for a maximum limit of 220 bar. All models use a standard 5/8″ UNF nitrogen valve. Regarding operating dynamics, the recommended compression ratio is set at 2.5, with a maximum allowable value of 4. It is important to emphasize that the mechanical life of the component is inversely proportional to the increase of this ratio; therefore, for demanding applications such as pulsation dampening, the nitrogen precharge pressure must be carefully calculated between 60% and 80% of the working pressure, taking into account pump specifications and system temperature.
Installation, Connections and International Certifications
Installation is designed to be highly flexible, allowing both horizontal and vertical mounting, provided that the nitrogen valve faces upward. Hydraulic connections range from standard BSP-F threads to more complex SAE 3000, SAE 6000, ANSI B16.5, UNI/DIN flanges, up to API Spec 6A type 6BX, Autoclave, or Grayloc connections for stainless steel series. To guarantee safety and compliance with global regulatory frameworks, these accumulators can be supplied upon request with conformity to the most stringent international certifications, including CE (PED), ATEX, ASME VIII, SELO, CRN, and DNV.