An energy storage device, a hydraulic accumulator is a pressure storage reservoir in which non-compressible hydraulic fluid is held under pressure by compressed gas. An accumulator is used in a hydraulic system to meet extremes in flow demand allowing the supply circuit to respond more quickly to any temporary demand and to smooth pressure pulsations.

Test Based Sizing Tips

One Shot Test Accumulator sizing
A 1 gallon accumulator  provides 12 cubic inches of oil at a 300 psi drop with a 1500 psi pre-charge.
A 4 liter accumulator provides 210 cubic cm of oil at a 21 bar drop with 104 bar pre-charge.

Cyclic Test Accumulator Sizing
V = Accumulator Volume
A = Piston Area
D = Pk-Pk Actuator Displacement

For Gallons
V = 0.03 x A(in2) x D(in)

For Liters
V =  0.007 x A(cm2) x D(cm)

For short duration, high flow demand tests, an accumulator bank can be used in place of a large hydraulic power unit. The bank can be charged with a small displacement pump, saving energy and reducing your equipment costs.

23 and 24 Hydraulic Service Manifolds (HSM)

The actuator mounted 23 and 24 Series Hydraulic Service Manifolds provide the interface between the actuator and the servo valve, accumulators and control valves as required by the hydraulic system. Benefits include:

  • Easy removal and installation of servo-valves without disconnecting hoses
  • System connection port locations designed to simplify hose routing
  • Maximum available servo-valve flow assured by exacting port alignment
  • Close coupling of accumulators for maximum performance

The 23 and 24 Series Hydraulic Service Manifolds differ only in the number of servo-valves they are designed to hold. The 23 Series is a single servo-valve design and the 24 Series is a dual servo-valve design. Setting the standard for actuator manifolds with advanced design, quality components, and variety of options the 23 and 24 Series HSMs are your best choice for all your testing applications.

Features

  • Pressure ramping — An electrically adjustable proportional valve allows you to ramp pressure from low to high or vice versa.

  • Accumulators — Close-coupled pressure and return accumulators positioned close to the servo-valve improves the high-frequency response characteristics of the actuator.

  • Pilot Pressure —  Auxiliary pilot pressure ports direct system hydraulic pressure to other system functions.

  • Pressure Control — An internal pressure control solenoid valve allows you to turn hydraulic pressure on and off via the system control electronics.

Options

  • Overload protection — Protects test articles from excessive or uncontrolled forces and provides for a controlled fluid dump.

  • Dual and 3 Stage Servo-valves — Allows the actuator to accept a number of servo-valves combinations and configurations.

  • Load limiting protection — Provides adjustable limits on the maximum force in either tension or compression the actuator can produce.

  • Flushing blocks — Bolts directly in place of the servo-valve and allows you to flush contaminants from the system.

  • Shutoff valves — Mounts directly between the servo-valve and the manifold and allows shutoff control. Very handy in dual valve setups allowing shut off of one valve, reducing maximum velocity but maintaining the same actuator force capability.

  • Large accumulators — Large accumulators can be added in demanding applications to improve performance.

  • Additional filtration — Additional filtration can be provided at the manifold to prevent servo-valve contamination problems. Particularly useful in large, ring-main systems where components are changed out on a regular basis providing opportunities for contamination