Aerial Work Platform · 2nd of 7

Aerial Work Platform Luffing Cylinder

Same concept as the crane luffing cylinder — different priority. Cranes optimise for load capacity. Aerial platforms optimise for one thing: the people standing on the platform must never fall. Fail-safe holding, smooth motion, certified overload protection — every design decision serves personnel safety.

50–350mmBore

≤3,000mmStroke

30 MPaPressure

SafetyFirst Priority

People on the Platform — Why This Luffing Cylinder Is Designed Differently from the Crane's

The mobile crane luffing cylinder (#17) holds a steel load — if the boom drifts by 10 mm, the load moves 10 mm. No injury. The aerial platform luffing cylinder holds a platform with workers standing on it — if the boom drifts, people lurch. If the boom drops, people fall from height. Aerial platform regulations (EN 280, ANSI A92, AS 1418.10) impose design constraints on the luffing cylinder that go beyond what crane standards require:

Fail-safe holding valve — mandatory

A counterbalance valve is not optional on an aerial platform luffing cylinder — it is mandatory by regulation. The valve must hold the platform with workers at any boom angle, even after a complete hydraulic hose failure. The valve must be mounted directly on the cylinder (not on a remote valve block connected by hoses).

Maximum lowering speed — limited

The boom lowering speed must not exceed specified limits — typically 0.4 m/s at the platform. A sudden boom drop (even 50 mm) can throw workers off balance. The counterbalance valve's metering orifice restricts the lowering flow, ensuring the boom descends smoothly regardless of operator input aggressiveness.

Korea Ever-Power manufactures the luffing cylinder as the second of seven aerial work platform hydraulic cylinders — with the safety architecture that EN 280 and ANSI A92 require for personnel-carrying equipment.

Technical Specifications

Parameter	Specification
Product	Aerial Work Platform Luffing Cylinder
Function	Boom up/down pitching — main driving force for platform height
Bore Diameter	50 mm – 350 mm
Rod Diameter	30 mm – 300 mm
Stroke	≤ 3,000 mm
Max Pressure	30 MPa
Application	Aerial Work Platform (boom lift, cherry picker)
Certification	ISO 9001 · EN 280 / ANSI A92 compatible · 100% tested

Smooth Motion — People Feel Every Jerk

A crane operator sits inside a cab — minor boom oscillations are barely noticed. Workers on an aerial platform basket stand in the open, 20–40 metres above ground — they feel every vibration, every jolt, every start/stop transient. If the boom motion is rough, workers grip the railing, stop working, and productivity drops. If the motion is too rough, workers refuse to use the platform.

Cushioned stroke ends — soft start, soft stop

Internal cushions (tapered sleeves at both stroke ends) decelerate the piston smoothly before it reaches the end cap — preventing the jolt that workers feel as the boom reaches its limit. Korea Ever-Power tunes the cushion orifice to match the platform's boom speed and inertia.

Low-friction seals — proportional response

High seal friction causes stick-slip at low speeds — the boom jumps in small steps instead of moving smoothly. Workers interpret this as a malfunction. PTFE-composite guide rings and low-friction polyurethane seals eliminate stick-slip, giving the operator smooth proportional control at any speed. Contact Korea Ever-Power for aerial platform luffing cylinder specifications.

Aerial platform luffing cylinder in urban application

Manufacturing Process

Bore honed to Ra 0.2–0.4 µm. Chrome 50–80 µm. Internal cushions machined at both ends. Counterbalance valve mounting pad machined on the barrel — the valve mounts directly on the cylinder with no intermediate hose. Rod eyes forged. Seals rated -30 °C to +80 °C, polyurethane + PTFE guides + low-friction rod seal. Every luffing cylinder is hydrostatic tested at 1.5× (45 MPa), drift tested (zero allowable boom drop under rated load), and lowering-speed tested — verifying that the platform descent rate does not exceed the EN 280 / ANSI A92 limit.

OEM & ODM

What You Provide

Platform model, boom type (articulating/telescopic), rated platform load, boom length and weight, required lift force, maximum lowering speed, bore/rod/stroke, system pressure, counterbalance valve spec, applicable safety standard (EN 280/ANSI A92), and boom pivot drawing.

What the Factory Delivers

Engineering drawing with bore, rod, stroke, internal cushions, counterbalance valve mounting, low-friction seal spec, and mounting dimensions. Hydrostatic + drift + lowering-speed test certificate. Seal kits. Browse the aerial work platform cylinder family and the Korea Ever-Power catalogue.

Workshop

FAQ

How does this differ from the crane luffing cylinder (#17)?

Lower pressure (30 vs 36 MPa — lighter loads), mandatory counterbalance valve (regulated, not optional), internal cushions (for smooth motion), lowering speed limit (EN 280 compliance), and drift test to zero tolerance (not the ≤5 mm/10 min limit used for excavator boom cylinders). The crane cylinder is engineered for maximum force; the platform cylinder is engineered for maximum safety.

What happens during a power failure at height?

The counterbalance valve locks the boom in position — the platform stays at its current height. Workers are safe but stranded until power is restored or a manual emergency lowering valve is activated. The emergency lowering valve allows gravity-assisted descent at a controlled speed — the luffing cylinder retracts slowly, lowering the platform to ground level.

Is the bore range (50–350 mm) used fully?

Yes — the range covers everything from small trailer-mounted platforms (50–80 mm bore, 10 m working height) to the largest self-propelled boom lifts (200–350 mm bore, 40+ m working height). The majority of rental-fleet boom lifts fall in the 100–200 mm bore range. Browse telescopic cylinders and forklift cylinders.