Operating principle of cartridge amplifier

PistonPower cartridge amplifier (CA) is a hydraulic single acting pressure amplifier integrated into the piston rod of hydraulic cylinder.

The hydraulic pressure amplifier is a device that converts the kinematic energy of oil (flow) into the static energy of oil (pressure) so that the amplified pressure is higher than the input pressure at the expense of output amplified flow being lower then input flow. The ratio between amplified output pressure and input pressure is the amplification ratio.

The basic principle of pressure amplification is based on reciprocal movement of two connected pistons with different area. Input pressure and flow acts on large piston which is moved to the end position. This generates higher output pressure and lower output flow on the small piston side. Afterwards the pistons move back to initial position and the cycle repeats itself.

Typical amplification frequency i.e. number of amplification cycles per second is 15-20Hz.
In case of no flow demand (e.g. at the end stroke of the cylinder) the frequency of amplification decreases to cover the internal leakage and maintain the high pressure on the outlet side.

Benefits of internal pressure amplification

PistonPower cartridge pressure amplifier is rated for max. amplified output pressure of 700 bar and is available with different amplification ratios to allow applications with various system pressure reach their full potential.
The benefit of pressure amplification is higher power density allowing either higher force with same cylinder size, same force with smaller cylinder size or downscaling of the hydraulic system and pressure source.
The benefit of integrating the hydraulic pressure inside the hydraulic cylinder is the compact package and increased safety thanks to the reduction of all external high-pressure hydraulic components (e.g. pipes, hoses, fittings).

Activation of amplification

The actuation of pressure amplification is automatic based on the actual load. If the system pump pressure is enough to overcome load, the amplification is not activated and the cylinder works as usual in a so called bypass mode. Once the system pump pressure is not enough to overcome the load, the amplification process starts automatically and increases the pressure inside the cylinder in a so called amplification mode.

The flow ratings of all the CA products refer to the max. cylinder input flow in the bypass mode.

Products overview

Model CA100 CA200 CA300
Amplification Ratio 2.8 2.0 2.8 2.0 2.4
Input Parameters
Port A1 Max. Pressure bar (PSI) 240 (3480) 350 (5076) 240 (3480) 350 (5076) 280 (4061)
Max. Flow lpm (gpm) 100 (26.4) 200 (52.8) 200 (52.8) 300 (79.3) 300 (79.3)
Port B1 Max. Pressure bar (PSI) 350 (5076)
Max. Flow lpm (gpm) 100 (26.4) 200 (52.8) 300 (79.3)
Output Parameters
Port A2 Max. Pressure bar (PSI) 700 (10152)
Max. Flow lpm (gpm) 12.4 (3.3) 17 (4.5) 11 (2.9) 18 (4.8) 15 (4)
Port B2 Max. Pressure bar (PSI) 350 (5076)
Max. Flow lpm (gpm) 100 (26.4) 200 (52.8) 300 (79.3)
Outer dimensions
Diameter mm (in) 69.9 (2.74) 79.6 (3.13) 99.6 (3.92)
Length mm (in) 305 (12) 455 (17.91) 520 (20.47)
Weight kg (lbs) 6.8 (15) 13 (28.7) 24.3 (53.6)


Smallest member of the family. Its higher amplification ratio and small size make it ideal for smaller applications with lower system pressure and input flow flow up to 100lpm, e.g. small (0.5t) demolition attachments like concrete crushers or pulverizers for mini-excavators.


An all-rounder in the middle of the product range. Thanks to multiple amplification ratio options (2.0 and 2.8), this model can satisfy applications with both low and standard system pressure and input flow up to 200lpm e.g. medium size (1t) demolition attachments like concrete crushers or pulverizers.


Largest and most popular product in the range. The amplification ratios 2.0 and 2.4 aim at high power application with medium system pressure and flows up to 300lpm e.g. large (2-4t) demolition attachments like concrete crushers or pulverizers.