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Tag Archive: cylinder

Proportional valve control calculation. Part 2.

Part 2. Proportional control in the regeneration mode.

Regen mode - proportional control

Fig.1. Regeneration mode schematic

See also:
Part 1. Proportional control of double acting hydraulic cylinder.
Online calculator for cylinder proportional control.

The goal of the calculation is definition of a cylinder velocity at the current operating voltage at the valve’s solenoid.
For calculations we need to know: cylinder and valve parameters (take them from manufacturer catalog), values of forces at cylinder rod (load) and pressure drop at return line (can be assumed as zero if unknown).

Summary:
2.1. Regeneration mode schematic
2.2. Regeneration Mode: Cylinder extension calculation
2.2.1. Balance of forces at the cylinder
2.2.2. Spool lands ratio and pressure drops at the spool lands
2.2.3. Hydraulic cylinder extension. System pressure calculation
2.2.4. Flow through spool lands: max. and at current voltage
2.3. Hydraulic cylinder retraction calculation
2.4. Final words….

Multi-Cylinders conduits calculation

Cylinders conduits flow

Cylinder’s flow

These calculations can help you to figure-out conduits (hoses, pipes or tubes) parameters (ID sizes, piston speed, flow velocity and cylinder’s force) for any qty of cylinders connected in parallel circuit.

Calculations Notes:

  • The recommended flow velocity in conduits you can find at the article Recommended flow velocity.
  • The assumption: if you use more than 1 cylinder in calculations, all cylinders have the same parameters (bore/rod diameters, stroke and friction)
  • The assumption: Pressure and Return lines conduits (flow source – flow divider and flow divider – tank) have the same ID size.
  • The assumption: the conduits between flow divider and cylinders have the same ID size.

Proportional valve control calculation. Part 1.

Part 1. Proportional control of double acting hydraulic cylinder.

See also:
Part 2. Proportional control in the regeneration mode
Online calculator for cylinder proportional control.

Fig.1. Double acting cylinder control.

Fig.1. Double acting cylinder control.

The goal of this calculation is a definition of a cylinder velocity at any percent of the operating control signal at the valve’s solenoid (voltage or amperage).
For calculations we need to know: cylinder and valve parameters (take them from manufacturer catalog), values of forces at the cylinder rod (load), and pressure drop at the return line (can be assumed as zero if unknown).

Summary:
1.1. Hydraulic cylinder extension calculation.
1.1.1. Spool lands ratio.
1.1.2. Pressure drops at the spool lands
1.1.3. Balance of forces at the cylinder.
1.1.4. System pressure calculation.
1.1.5. Flow through spool lands: max. and at current voltage.
1.2. Hydraulic cylinder retraction calculation.
1.3. Full stroke time calculation.