Trailing Suction Dredger Hanger Cylinder

Deploy

Cylinder extends to swing the hanger outboard. The suction pipe lowers toward the water under controlled speed. Lowering rate is metered to prevent free-fall.

Dredge

The hanger cylinder holds position while the heave compensation cylinder (#5) absorbs wave motion. The hanger provides a stable pivot point for the pipe's angular movement.

Recover

Cylinder retracts with up to 3,000 KN of pull force, hauling the pipe assembly up against its own weight plus the weight of water and sediment trapped inside. This is the peak-force phase.

Stow

The pipe is secured against the hull for transit. Load-holding valves lock the hanger in position — preventing the pipe from swinging in rough seas during the voyage to the disposal site.

The hanger supports a swinging suction pipe (5–30 tonnes depending on TSHD size) in open-sea conditions. The pipe pendulates with wave motion, creating dynamic loads that cycle continuously. The cylinder's pin joints, barrel, and rod must be rated for fatigue — not just static load.

If the dredger must stop suddenly (engine failure, collision avoidance), the suction pipe must be recovered rapidly before it drags on the seabed or tangles with the vessel. The hanger cylinder's retraction speed and force must handle emergency recovery under worse-case conditions — full pipe weight plus dynamic wave loading.

The hanger cylinder operates in the worst corrosion zone on a vessel — the splash zone where alternating wet/dry cycles accelerate corrosion 5–10x faster than continuous immersion. Laser-clad or ceramic rod coating, FKM seals, and marine-grade epoxy barrel coating are standard for hanger cylinder installations.

Complete hanger cylinder sets for new-build TSHDs, designed from the vessel's GA drawings and suction pipe specifications. Lead time: 8–12 weeks from drawing approval.

Form-fit-function replacements for existing TSHDs — reverse-engineered from originals or from vessel drawings. Upgraded seals, surface treatment, and valve integration included.

Pre-packaged seal kits for field replacement. Each kit contains the complete seal set for one cylinder — rod seal, piston seal, wiper, guide rings, O-rings — packed in a labelled marine-duty container.

Can this cylinder be retrofitted on an existing vessel?

Yes. Korea Ever-Power manufactures replacement cylinders for existing dredging vessels, including reverse-engineering from worn-out originals or from the vessel's original equipment drawings.

What classification society approvals are available?

Bureau Veritas (BV), DNV, Lloyd's Register (LR), ABS, and CCS documentation and witnessed testing can be provided on request.

What surface treatment options are available for saltwater service?

Ceramic spraying (HVOF), laser cladding (Inconel/Stellite/nickel-chrome), and standard hard chrome plating. Selection depends on the operating environment, maintenance schedule, and target service life.

What is the typical lead time?

Standard lead time is 8–12 weeks from drawing approval. Emergency/rush orders for operating vessels can be accommodated in 5–6 weeks. Contact the engineering team for current availability.

Can integrated valves be included?

Yes — load-holding valves, counterbalance valves, sequence valves, relief valves, check valves, and pressure measuring joints can be machined directly into the cylinder body. This reduces external piping, potential leak points, and installation time. Browse mobile machinery hydraulic cylinders and industrial engineering hydraulic cylinders for related heavy-duty applications.

"The hanger cylinders on our 12,000 m³ TSHD have been in service for 14 months. The ceramic-coated rods are handling the constant saltwater spray without any visible surface degradation. Previous hard-chrome rods on the same vessel showed pitting within 8 months."

Capt. M. Andersen — Fleet Captain, Danish dredging company

"We needed 2 hanger cylinders with exact dimensional match to our Vosta LMG suction pipe frame. Korea Ever-Power worked from our GA drawings and delivered cylinders that bolted straight in without any adapter plates. Good dimensional accuracy on the mounting pins."

G. Koopman — Maintenance Manager, Netherlands

"Hanger cylinders for a mid-size TSHD (3,500 m³). Performance is as specified. Delivery took 8 weeks — we were hoping for 6. The rod surface finish (Ra 0.2 µm measured) is very good. Seal leakage: zero after 2,400 operating hours."

A. Diallo — Chief Engineer, Senegal

"Second order from Korea Ever-Power — hanger cylinders for our second TSHD. Same spec as the first order (2024), same quality. Having a consistent, reliable supply source for dredger hydraulic cylinders is worth a lot when you operate vessels 300+ days per year."

Y. Takahashi — Procurement Manager, Japanese dredging contractor

"The load-holding valves integrated into the hanger cylinder body eliminated the risk of uncontrolled pipe drop during a hydraulic supply failure. This was a class society requirement (DNV) that our previous external valve arrangement did not fully satisfy. The integrated design passed the DNV survey without comment."

Eng. C. Olsen — Classification Compliance, Norway