This revision models both chamber pressures and connects a 5/2 valve's alternating supply/exhaust paths to the moving piston while keeping the force calculation explicitly ideal and static.
Double-Acting Cylinder Force Explorer
Enter bore, rod-to-bore ratio, declared supply pressure and declared exhaust/backpressure. The worksheet balances pressure on both piston faces for ideal extend and retract states.
Equation Used
- The cylinder is single-rod and double-acting with circular bore and rod sections.
- The same declared supply and exhaust/backpressure values are alternated between chambers for comparison.
- Pressure is uniform on each effective piston face.
- The animation prescribes piston travel and valve timing; it does not solve flow or dynamics.
- Seal friction, leakage, pressure drop, compressibility transients, cushioning, side load, buckling, mounting, speed, duty, component ratings and safety functions are excluded.
Adds opposing-chamber pressure to the ideal force balance and replaces disconnected artwork and unsupported performance/safety advice with connected 5/2 routing.
A directional valve alternates the two chamber pressure states
ISO 15552 defines a pneumatic cylinder as a piston and piston rod operating within a cylindrical bore and notes that pneumatic systems transmit and control power through gas under pressure. In a double-acting arrangement, a directional valve supplies one chamber while connecting the other to exhaust, then reverses those paths.
The animation shows that routing topology. Its piston motion is prescribed and does not predict speed or transient pressure.
Component selection is application-specific
ISO 15552 standardizes key interchangeability dimensions for its stated 10 bar series; it does not make every cylinder suitable for every load or duty. Actual selection must follow the exact cylinder, valve, tubing, mounting and control documentation.
Balance pressure force on both piston faces
Festo Didactic gives theoretical cylinder force as pressure times effective area and distinguishes the full piston face from the smaller rod-side effective area. Including declared pressure on the nominal exhaust side produces the two net-force balances shown here.
Actual force can be lower because of friction, pressure losses and other effects.
A 50 mm bore declared-pressure example
For a 50 mm bore, a 40% rod-to-bore ratio gives 19.63 cm² full area and 16.49 cm² annular area. With 6 bar supply and zero declared exhaust pressure, ideal extend force is 1178 N and ideal retract force is 990 N.
Static ideal force is not dynamic performance
The worksheet does not predict cylinder speed, cycle time, impact, cushioning, heat, air consumption, leakage, breakaway, holding, buckling, service life or safe load. A 5/2 valve route alone does not provide a safety-rated stop or load-holding function.
Unsupported response times, tolerances, lifetimes, branded production cases, accuracy, efficiency, costs, troubleshooting and lifting advice are removed.
Pneumatic cylinder questions
Why is ideal retract force lower?
The rod removes effective area from the rod-side piston face.
Why include exhaust pressure?
Any opposing-chamber pressure contributes an opposing force.
Does the result equal measured force?
No. It is an ideal static balance.
Does a 5/2 valve hold a load safely?
This worksheet makes no holding or safety claim; use the exact risk assessment and rated components.
Pneumatic cylinder references
- ISO 15552:2018: current pneumatic-cylinder scope, piston/rod/bore definition, 10 bar series and standardized interchangeability dimensions.
- Festo Didactic, Pneumatics—Advanced Mechatronics System: theoretical force F=P A, full piston area on extend, reduced rod-side area and actual-force limitations.
- Parker P1F ISO pneumatic-cylinder catalogue: manufacturer theoretical-force tables versus applied pressure and effective areas.
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