How It Works

The Synchronization Challenge

When multiple hydraulic cylinders must move together (parallel operation), differences in friction, load, and manufacturing tolerances cause them to move at different speeds. Without synchronization, cylinders will "get out of step" and potentially damage equipment or cause uneven motion.

Synchronization Methods

1. Flow Dividers (Rotary or Spool Type)

  • Splits flow equally between multiple outlets
  • Accuracy: Typically 2-5% over full stroke
  • Errors accumulate over stroke length
  • Cost-effective for moderate accuracy needs

2. Servo/Proportional Valves with Feedback

  • Uses position sensors (LVDT, magnetostrictive) on each cylinder
  • Electronic controller adjusts flow continuously
  • Accuracy: 0.1-1% depending on system
  • Higher cost, requires electronics and programming

3. Mechanical Linkage

  • Physical connection between cylinders (beams, chains, cables)
  • Accuracy: Very high if rigid connection
  • Limited to specific geometries
  • May add complexity and weight

Error Accumulation

For flow dividers, synchronization error accumulates over the stroke:

Total Error = Stroke x (Error% / 100) x Number of Cycles

Without periodic re-synchronization, error compounds over multiple strokes.

Flow Divider Synchronization System PUMP Q_total FLOW DIVIDER Q/3 Q/3 Q/3 Cylinder 1 Cylinder 2 Cylinder 3 Sync Error LOAD Platform Error Accumulation: Each stroke adds to positional difference Re-synchronization required at stroke end or periodically

Selecting the Right Method

  • Accuracy < 5%: Standard flow dividers usually sufficient
  • Accuracy 1-5%: High-quality flow dividers or proportional valves
  • Accuracy < 1%: Servo valves with position feedback required
  • Accuracy < 0.1%: Mechanical linkage or high-end servo systems

Cylinder Synchronization Calculator

Analyze synchronization requirements and select the appropriate method for parallel cylinder operation. Compare flow dividers, servo valves, and mechanical linkage.

Cylinder Configuration

System Parameters

Load Distribution

Max difference between cylinders

Accuracy Requirements

Select Synchronization Method

Flow Divider

Accuracy: 2-5%
Cost: Low-Medium

Servo Valve

Accuracy: 0.1-1%
Cost: High

Mechanical Link

Accuracy: <0.1%
Cost: Variable

Simulated Position Error

4.0 mm
Maximum Position Error Over Stroke

Flow Divider Requirements

Flow per Cylinder --
Divider Sections Required --
Extension Speed --
Extension Time --

Synchronization Error Analysis

Method Typical Accuracy --
Position Error per Stroke --
Error After 10 Strokes --
Re-sync Interval Needed --

Force Analysis

Force per Cylinder (avg) --
Max Force (with imbalance) --
Available Force per Cylinder --
Force Margin --

Methods Comparison

MethodAccuracyMeets Req?Relative Cost
Flow Divider (Std) 5% -- $
Flow Divider (Hi-Q) 2% -- $$
Proportional Valve 1% -- $$$
Servo w/ Feedback 0.5% -- $$$$
Mechanical Linkage <0.1% -- $$-$$$$

Recommendation

Based on your requirements, a standard flow divider should provide adequate synchronization accuracy.

Reference

Error per Stroke:

Error = Stroke x (Accuracy% / 100)

Cumulative Error:

Total Error = Error x N_strokes (worst case)