3500m3 Trailing Suction Hopper Dredger

Overall Length: 91.90m

Length Between Perpendiculars: 87.00m

Moulded Breadth: 16.0m

Moulded Depth: 7.0m

Designed Draft: 5.60m （full load）

Hopper Capacity: 3500m³

Mud Carrying Capacity: 4592t

Maximum Dredging Depth (below designed waterline): 18.0m

Crew Capacity: 32 persons

Sea Area of Operation: Coastal areas of various ports

Self-sustaining Capacity: 30 days (calculated based on 24-hour daily operation)

Navigational Speed: 9kn (free sailing); 2~3kn (dredging operation)

Dredging Targets: Silt, soft clay, loose sandy soil, cohesive soil with medium or lower hardness

Environmental Design Conditions

Atmospheric Temperature: -15°C ~ 40°C

Seawater Temperature: 5°C ~ 32°C

Tidal Current Velocity: 2m/sec

Classification Design Standard: CCS "Rules for Classification and Construction of Sea-Going Steel Ships (2001)", Chapter 14 "Dredgers"

Main Power & Core Dredging Equipment

Propulsion Main Engine

Model: G6300ZC16B, G6300ZC17B

Power: 2×1471KW (2×2000PS)

Rotating Speed: 575r/min

Quantity: 2 sets

Diesel Generator Set

Model: W12V135A21WCZf

Power: 300KW

Rotating Speed: 1500r/min

Quantity: 3 sets

Mud Pump Main Engine

Model: G6300ZCB

Type: Four-stroke, in-line, water-cooled, direct injection, non-reversible, supercharged marine diesel engine

Cylinder Parameter: 6 cylinders, 300×380mm (bore×stroke)

Rated Power: 750KW per unit

Rotating Speed: 500r/min

Single Unit Weight: 9800kg

Total Weight for 2 Units: 19600kg

Manufacturer: China National Internal Combustion Engine Factory

Supporting Configuration: Equipped with dual lubricating oil Pumps, one spare lubricating oil pump, 24V servo motor switch on bridge, electric tachometer, exhaust port square-to-round joint

Quantity: 2 sets

Mud Pump (Full Detailed Parameters)

Type: Horizontal single-stage centrifugal pump (ZC approved)

Manufacturer: Shanghai Donghai Electromechanical Co., Ltd.

Clear Water Flow Rate: 7500m³/h

Rated Head: 20m

Rated Rotating Speed: 250r/min

Installed Power: 750KW

Suction and Discharge Pipe Diameter: 700mm

Quantity: 2 sets

Gearbox & Coupling

High Elastic Coupling

Model: BC63/15-140

Rated Torque: 40KN.m

Quantity: 2 sets (CCS approved), manufactured in Chongqing

Main Gearbox

Model: GWC49/54

Speed Ratio: 3:1

Quantity: 2 sets (CCS approved), manufactured by Hangzhou Gearbox Factory

High Elastic Clutch & Reduction Gearbox

High Elastic Clutch Model: LS2320

Clutch Rated Torque: 20KN.m

Clutch Maximum Torque: 60KN.m

Reduction Gearbox Model: GWC39/41

Gearbox Speed Ratio: 2:1

Equipped with: GZB02 mud pump working condition testing device (acousto-optic alarm when torque >1.5 times the rated value), remote control system, pneumatic control box, torsion angle slip monitoring device

Structural Feature: Coaxial input and output

Quantity: 2 sets (CCS approved), manufactured by Shanghai 711 Research Institute

Key Auxiliary Equipment

Air Compressor

Main Compressor Model: CZ-0.36/30F

Type: Vertical, air-cooled, two-stage compression, belt drive

Displacement: 21.6m³/h

Working Pressure: 3Mpa

Rotating Speed: 600r/min

Cylinder Parameter: Stage 1 Φ107.95mm, Stage Ⅱ Φ38.10mm, stroke 76.2mm

Supporting Motor: Y132S-4, 5.5KW, 380V 50Hz, 1000r/min

Emergency Compressor Diesel Engine: Model S1110 (Changzhou Diesel Engine Factory), 14.7KW, 2000r/min

Configuration: With electric control box

Quantity: 3 sets (ZC approved, electromechanically complete supply), manufactured by Wenling Songmen Hongwei Compressor Factory


Updated Machinery

Power Generation: We have replaced the generator sets with two 400kW units (renewed in 2016), featuring Weichai diesel engines and Lan Dian alternators. Dredging Equipment: Both the drag head and the winch in the hopper have been upgraded to larger sizes. The A-frames for both the drag head and hopper were upgraded and replaced in 2016; they are significantly reinforced and larger than the previous ones. General Condition: The bridge navigation and communication equipment has been extensively updated. All external hydraulic piping is made of stainless steel. The diesel engines and other machinery undergo major maintenance annually. The vessel just came out of dry dock in June 2005, and all underwater works are in perfect condition. Other Updates: The sewage treatment plant has been newly replaced with new piping installed. Note: These equipment updates and renovations are not reflected in the original equipment list. 


Advantages: The vessel is in excellent condition and currently under working. It is ready for immediate operational deployment, offering a high Return on Investment (ROI). The payback period for this TSHD is relatively short.

Dredging Sequence for TSHD under Various Conditions

Insufficient Pre-dredging Depth / Draft Restrictions
Utilize high tide levels to dredge shallow sections first. Proceed from shallow to deep areas, gradually widening and deepening the channel.

Thick Sediment Layers, Large Volume & Long Duration with Siltation
Dredge shallow sections first and deepen incrementally. Wait until the depth across the trench is relatively uniform before deepening further.

Reason: To allow sedimentation in the deeper sections to be dredged out in a single pass during the later stages.

Unidirectional Current
Start dredging from the upstream end and progress downstream. This utilizes the current to flush away disturbed sediment, enhancing dredging efficiency.

Ebb-Tide Dominated Estuaries
Utilize tidal currents by dredging from the inside (upstream) towards the outside (seaward).

Cross-section: Shallow Sides, Deep Center
Dredge the two sides first.

If one side has a thicker sediment layer: Dredge the thicker side first. Once depths on both sides are similar, deepen the whole section gradually.

Reason: To avoid forming steep slopes that could lead to collapse (landslides).

Flat Topography with Hard Clay
Dredge the entire channel width uniformly, layer by layer.

Reason: To prevent the formation of ridges or furrows (gullies), which would make subsequent leveling difficult.

Uniform Pre-dredging Depth (Center & Sides)
Dredge the sides first, then proceed to the center.

High Siltation & Flow Parallel to Channel Axis
First, dredge a deep pilot trench through the shallow areas to create a path, then gradually widen it.

Reason: To utilize the water flow to scour the trench and reduce the volume of back-siltation.

FAQ

Q1: What kind of Dredging Projects is this 3500m³ Trailing Suction Hopper Dredger most suitable for?

A1: This dredger is specially optimized for maintenance Dredging projects of coastal ports, waterways and harbors. Its 18m maximum dredging depth, 2~3kn professional dredging speed and 3500m³ middle-capacity mud hopper perfectly match the operational demands of regular maintenance dredging, which can efficiently remove silt, soft clay and loose sandy soil deposits, and maintain the normal water depth and navigation conditions of waterways and port basins.

Q2: What is the current condition of this 3500m³ trailing suction hopper dredger?

A2: The vessel's overall condition is extremely well maintained with strict and regular professional maintenance and inspection carried out on all core systems including the power unit, mud pump system, hull structure and auxiliary equipment. All key components and mechanical parts are in excellent working condition, with no major repair records; the hull structure is intact without deformation or corrosion, and all approved equipment (CCS/ZC) operates stably, ensuring reliable and efficient operation for subsequent dredging projects.