45m Backhoe Dredger - Hitachi EX2500   Technical Specification

1. Basic Vessel Information

• Vessel Type: Non-self-propelled box-type backhoe dredger (no mud tank), coastal engineering vessel

• Application: Waterway Dredging, hydraulic Reclamation works

• Hull Structure: All-welded steel hull; longitudinal framing (transverse framing for side shell only)

• Design Standards:

• MSA "Rules for the Statutory Survey of Sea-going Ships Engaged in Domestic Voyages" (2020)

• CCS "Rules for the Construction and Classification of Steel Sea-going Ships" (2018)

• Navigational Area: Coastal area

• Operating Personnel: 6 persons

• Sea Keeping Capacity: 6 days

• Unmanned Towing: Yes

2. Main Dimensions

• Overall Length (LOA): 44.55 m

• Length Between Perpendiculars (LPP): 44.55 m

• Moulded Breadth: 18.00 m

• Moulded Depth: 3.80 m

• Design Draft: 2.10 m

• Summer Freeboard: 1710 mm

• Gross Tonnage (GT): 947

• Net Tonnage (NT): 284

• Frame Spacing: 0.60 m

• Beam Camber: 0.20 m (typical, per coastal vessel standard)

3. Main Dredging Equipment

• Equipment Type: Backhoe Excavator Hitachi EX2500 

• Maximum Bucket Capacity: 12 m³ & 6.8 m³ (mud bucket and rock bucket)

• Maximum Swing Radius: 17 m

• Maximum Dredging Depth: 15 m

• Spud Piles: 2 nos (stowed on main deck during towing; inserted into seabed during operation)

• Spud Well Location: Fr30, 7m from centerline (port/starboard)

4. Power Supply System

4.1 Main Diesel Generator Set

• Diesel Engine Model: Cummins 6CTA8.3-GM115

• Type: 6-cylinder, 4-stroke, inline, turbocharged, intercooled

• Rated Power: 115 kW

• Rated Speed: 1500 rpm

• Bore × Stroke: 114 × 135 mm

• Fuel Consumption Rate: 215 g/kW·h

• Starting Method: Electric start (with spring backup)

• Generator Type: Brushless, self-excited constant voltage synchronous generator, 3-phase 4-wire

• Generator Rated Power: 100 kW

• Quantity: 1 set

4.2 Auxiliary Diesel Generator Set

• Diesel Engine Model: Cummins 6BT5.9-GM83 (can be replaced with a Cummins QSK45)

• Type: 6-cylinder, 4-stroke, inline, turbocharged, intercooled

• Rated Power: 83 kW

• Rated Speed: 1500 rpm

• Bore × Stroke: 102 × 120 mm

• Fuel Consumption Rate: 215 g/kW·h

• Starting Method: Electric start (with spring backup)

• Generator Type: Brushless, self-excited constant voltage synchronous generator, 3-phase 4-wire

• Generator Rated Power: 50 kW

• Quantity: 1 set

4.3 Monitoring & Alarm System

• Audio-visual alarm for low lube oil pressure and high fresh water temperature

• Automatic shutdown alarm for ultra-low lube oil pressure and overspeed

5. Key Pumps & Equipment

5.1 Oil Pumps

• Fuel Transfer Pump: Model YCB-3.3/0.6 (horizontal gear pump), Flow Rate 3.3 m³/h, Pressure 0.6 MPa, Motor Power 1.5 kW, Quantity 1 set

• Waste Oil Manual Pump: Model CS-40y, Flow Rate 3.9 m³/h, Pressure 0.25 MPa, Quantity 1 set

5.2 Water Pumps

• Fire/General Service Pump: Model 80CWZ-8 (horizontal self-priming centrifugal pump), Flow Rate 60 m³/h, Head 0.42 MPa, Motor Power 15 kW, Quantity 1 set

• Bilge General Service Pump: Model 80CWZ-8 (horizontal self-priming centrifugal pump), Flow Rate 60 m³/h, Head 0.42 MPa, Motor Power 15 kW, Quantity 1 set

• Auxiliary Engine Room Bilge Manual Pump: Model CS-40H, Flow Rate 3.9 m³/h, Pressure 0.25 MPa, Quantity 1 set

• Sanitary Sewage Grinder Pump: Model FSC-5, Flow Rate 5 m³/h, Pressure 0.1 MPa, Motor Power 1.5 kW, Quantity 1 set

• Fresh/Seawater Supply Pump: Model 1.5CWX-2, Flow Rate 3 m³/h, Head 0.4 MPa, Motor Power 2.2 kW, Quantity 3 sets

5.3 Fans & Other Equipment

• Auxiliary Engine Room Axial Flow Fan: Model CZ-45B, Air Volume 6500 m³/h, Total Pressure 470 Pa, Motor Power 2.2 kW (reversible), Quantity 1 set

• Kitchen Supply Fan: Model CWZ-250G-II, Air Volume 1810 m³/h, Total Pressure 200 Pa, Motor Power 0.25 kW, Quantity 1 set

• Toilet Exhaust Fan: Model CWZ-200G-II, Air Volume 920 m³/h, Total Pressure 140 Pa, Motor Power 0.06 kW, Quantity 1 set

• Fresh/Seawater Gravity Tank: Capacity 1 m³ each, Quantity 2 sets

• Main Generator Spark Arrestor Silencer: Model VTJZ-100, Quantity 1 set

• Auxiliary Generator Spark Arrestor Silencer: Model VTJZ-80, Quantity 1 set

6. Hull Structure & Outfitting

6.1 Hull Compartments

• Watertight Transverse Bulkheads: 5 nos (Fr8, Fr30, Fr45, Fr60, Fr72)

• Compartments (from stern to bow): Stern Peak Tank (port/starboard), No.1 Void Tank (port/starboard), No.2 Void Tank (port/starboard, including fuel tank), No.1 Ballast Tank (port/starboard/starboard center) + Auxiliary Engine Room, No.2 Ballast Tank (port/starboard/port center/starboard center), Fore Peak Tank

6.2 Mooring & Anchoring Equipment (Outfitting Number: 413)

• Bow Anchors: 2 nos, Hall anchor, 1590 kg each

• Anchor Chain + Rope: 2 sets (5.5m AM2 Φ34mm stud welded anchor chain + 310m Φ32mm steel wire rope)

• Mooring Ropes: 4 sets, 160m Φ32mm 8-strand nylon rope

• Towing Rope: 1 set, 190m Φ24mm steel wire rope

• Electric Anchor Winch: 1 set, Single motor with double drum (capacity: Φ32mm × 310m)

• Bitts: 12 nos (2 double cross bitts + 10 side bitts)

6.3 Fire Fighting Equipment

• Fire Hose Boxes: 6 sets (with hose + combination spray/straight jet nozzle)

• Portable Fire Extinguishers: 20 nos (12 dry powder 5kg, 4 CO₂ 7kg, 4 foam 9L)

• Firefighter's Outfit: 1 full set

• Fire Axes: 2 nos

• Fire Buckets: 3 nos

• Sand Boxes: 3 nos

• Auxiliary Engine Room Extinguishers: 3 nos (1 foam 9L, 1 CO₂ 7kg, 1 dry powder 8kg)

6.4 Life Saving Equipment

• Inflatable Life Rafts: 2 sets, Throw-over type, 6 persons each

• Life Jackets: 8 pieces

• Immersion Suits: 6 pieces

• Lifebuoys: 4 nos (2 with buoyant line, 1 with self-igniting light)

• Rocket Parachute Flares: 12 nos

• Emergency Position Indicating Radio Beacon (EPIRB): 1 set

• VHF Radios: 3 sets (1 in control room, 2 near life rafts)

6.5 Signaling Equipment

• Navigation Lights (collapsible mast and stern light pole)

• Top Deck Floodlights: 3 nos (illuminating stern working deck)

7. Piping Systems

7.1 Pipe Materials & Connections

• Bilge/Ballast/Fire/Deck Drainage: Galvanized Steel Pipe, Flange/Welding connection

• Fuel Oil: Steel pipe, Flange/Welding connection

• Fresh Water: Galvanized steel pipe/Copper pipe, Flange/Welding/Thread connection

• Seawater: Galvanized steel pipe, Flange/Welding connection

• Exhaust: Steel pipe (insulated + galvanized iron sheet cladding), Welding connection

• Ventilation: Steel plate/Galvanized iron sheet, Welding/Riveting connection

7.2 Key Systems

• Ballast Water System: Filled/discharged by fire/ballast general service pump or bilge general service pump

• Bilge System: Electric bilge pump + manual backup pump; equipped with mud box, non-return valve and high-level alarm

• Fire Fighting System: 1 main fire pump + 1 standby pump (bilge pump); fire hydrants throughout the vessel + international shore connection

• Fresh/Seawater Supply System: 3 supply pumps + 1 fresh/seawater gravity tank each; seawater for toilet flushing

• Sanitary Sewage Treatment System: Sewage storage tank + grinder pump; meets MEPC discharge requirements (≥3nm for treated sewage; ≥12nm for untreated sewage)

• Fuel Oil System: 2 light diesel storage tanks + 1 transfer pump; equipped with quick-closing valve and self-closing liquid level gauge

• Waste Oil System: Manual waste oil pump + international shore connection for onshore disposal

8. Ventilation Systems

• Auxiliary Engine Room: Forced mechanical ventilation (1 reversible axial flow fan); shutoff control outside engine room

• Kitchen: Mechanical supply ventilation

• Toilets: Mechanical exhaust ventilation

• Other Cabins: Natural ventilation

9. Machinery Maintenance Equipment

• Bench Grinder: 1 set, Double-wheel (coarse/fine), Φ150mm, 0.25kW

• Bench Drill: 1 set, Model Z4112-1, Drilling diameter Φ12mm, 0.37kW

• Bench Vise: 1 set, Swivel type, Jaw width 150mm

• Manual Chain Hoists: 2 sets, Model STH2.0, Lifting capacity 2t, Lifting height 5m

• Workbench: 1 set

• Tool Rack: 1 set

10. Design Environment Conditions

• Seawater Temperature: 32℃

• Ambient Temperature: 45℃

• Atmospheric Pressure: 0.1MPa

  Relative Humidity: 60%

  Fuel Type: 0#/-10# diesel oil
  
  
  hydraulic rock break hammer 
  
  EX2500 Backhoe Dredger
  

• 

  
  
  

• Applications

• Coastal port & harbor dredging

• Navigation channel excavation & maintenance

• Small‑scale reclamation & land creation

• Berth, basin & waterway sediment removal

• Rock & hard soil dredging in confined waters

• Nearshore foundation & cofferdam cleaning

  Advantages

• EX2500 heavy‑duty backhoe with strong digging force & high efficiency

• 15m³ large bucket for high output per cycle

• 8.57m max digging depth for versatile coastal jobs

• Wide beam (18m) & shallow draft for excellent stability

• Full‑slewing operation for precise positioning

• Dual generators (100kW + 50kW) for reliable power supply

• Complete CCS certificates valid for coastal operation

• Full fire‑fighting & lifesaving equipment compliant with regulations

• Flexible ballast system for trim & stability control

• Simple structure, easy operation & low maintenance cost

• Unmanned towing allowed for convenient mobilization
  
  
  
  FAQs:   

• Q: What are the core working parameters of this backhoe dredger?

• A: It has a maximum bucket capacity of 12m³ and 6.8m³(for clay, mud, and for rock & coral reefs,), and a maximum dredging depth of 15m, suitable for coastal dredging and reclamation projects.

• Q: What power system does the dredger adopt?

• A: It is equipped with two Cummins generator sets: a 115kW main generator (model 6CTA8.3-GM115) and an 83kW auxiliary generator (model 6BT5.9-GM83), with an optional Cummins QSK45 replacement for the auxiliary engine.

•