The FOX SB Series Manual Safety Block is a fundamental device specifically designed to protect the hydraulic accumulator from overpressure within hydraulic systems. Its installation on the oil side ensures strict control and safe operation of the entire hydraulic system in the event of abnormal pressure peaks.

Construction Features and Materials

The strength and reliability of this component are ensured by its construction materials. The standard block body is made of galvanized steel, designed to withstand high levels of mechanical stress. For applications requiring a higher degree of corrosion resistance, the block is also available upon request in a stainless steel version. Regardless of the selected body material, the series safely supports a maximum operating pressure of 350 bar. The standard fluid operating temperature is within a range from -20 to +80 °C.

Integrated Components

The FOX SB Series Manual Safety Block stands out for its high level of completeness, combining several essential fluid-control elements in a single compact solution. It internally consists of:

  • A shut-off valve dedicated to blocking the flow.
  • A safety valve for pressure calibration and holding.
  • A discharge knob.
  • A dedicated provision with a hole for pressure gauge connection. In addition, to meet stricter regulatory requirements in industrial plants, the device is also available with a safety valve directly tested by a third-party certification body.

Available Variants and Models

The range includes multiple technical versions in order to adapt to different accumulator volumes and the related flow-rate requirements defined by the project.

SBO, SBOM, SB1, SB2 and SB3 Models

This family of components is recommended for coupling with FOX accumulators with volumes ranging from a minimum of 0.05 litres up to a maximum of 50 litres. They offer internal fluid passage diameters of 8 mm and 10 mm, handling peak hydraulic flow rates of 50 l/min and 80 l/min respectively.

SB110, SB111, SB112 and SB113 Models

Designed to operate with accumulators from 0.05 to 50 litres, these manually operated models feature an enlarged 12 mm passage diameter, allowing a nominal flow rate of up to 120 l/min. For the specific SB0, SBOM, SB110, SB111, SB112 and SB113 versions, the product code can be configured according to the different specific connection configurations required by the system.

SB4, SB5 and SB6 Models

The intermediate SB4 model is specifically suitable for volumes from 2.5 to 10 litres. The high-capacity SB5 and SB6 versions are fully suitable for operation on volumes from 10 litres, exclusively with a 2-inch connection, up to 50 litres. The passage diameters for these high-end models are 20 mm for the SB5 and 32 mm for the SB6, consequently guaranteeing significant flow rates of 190 l/min and 295 l/min respectively.

Connections and Adapters

In addition to the standard hydraulic connections widely specified in the catalogue for the accumulator side, with threads from 1/2″ BSP-F to 2″ BSP-M, and for the system side, from 1/2″ BSP-F to 1-1/2″ BSP-F, further types of connections are available from the manufacturer. If the user’s specific application requires it, direct reference can be made to FOX VS, NS, SAE3000 and SAE6000 Series adapters.

Technical Summary Table