First Chinese intelligent tugs built

Chinese shipbuilding took a technology leap when two intelligent ice-breaking tugs were completed for Tianjin Port

A dual-tug newbuilding project has generated a seismic shift in Chinese tugboat construction enabling a shipyard and owner to extend their digitalisation capabilities.

Tianjin Port Tug Co took delivery of a unique pair of ice-breaking azimuth stern drive (ASD) tugboats on 20 May 2019.

Jin Gang Lun 31 and Jin Gang Lun 32 were built by Zhenjiang Shipyard in Jiangsu Province as the first intelligent vessels in China. They both combine aspects of ice-breakers, towing tugs and pilotage vessels in their design and operation.

They were the first vessels built to have the China classification society CCS’ Intelligence notation with systems on board to monitor fuel and engineroom systems’ performance and condition.

Jin Gang Lun 31 and Jin Gang Lun 32 are based on Robert Allan’s ASD 40-35 design and with CCS’ requirements for lower emissions, vibration, noise and energy consumption.

Zhenjiang Shipyard says the delivery of these two intelligent tugs “symbolises a substantial breakthrough in upgrading from automation to intelligentisation in Chinese ASD tugboats”.

They were awarded the CCS class notation i-Ship, with sub-notations of N-intelligent navigation; M-intelligent machinery space, E-intelligent energy management and I- intelligent for the integral platform.

Robert Allan says these vessels will operate “in a safer, more efficient and environmental-friendly manner due to the improved automation system, better operational data collection and analysis” which will enhance operational guidance for Tianjin Port’s entire fleet.

The tugs will be used to transport pilots in rough sea conditions in Tianjin Port, in China’s Bohai Bay which was one of the reasons for reducing noise and vibration on these vessels. To accommodate pilot transfer, Robert Allan included a boarding system in their design after receiving input from Tianjin Port and pilot station personnel.

For pilot transportation, these tugs achieved free running speeds of 14.48 knots during sea trials.

Jin Gang Lun 31 and Jin Gang Lun 32 joined Tianjin Port’s existing towing fleet to provide ship docking, unberthing and coastal towing services within the port areas. They both have bollard pull ahead of 36 tonnes.

Jin Gang Lun 31 and Jin Gang Lun 32 have Ice Class B hulls as they will be used for ice-breaking services during winter.

Robert Allan says stability and safety considerations were given the highest priority in developing the design.

“Watertight bulkheads are arranged so that even if the largest compartment is flooded the vessel will remain afloat with a dry main deck,” the naval architects explain. “An effort was made to achieve good hydrodynamic and sea keeping performance, while the wheelhouse was designed to maximise visibility for the master.”

Engineroom systems

Main propulsion on Jin Gang Lun 31 and Jin Gang Lun 32 comprises a pair of Wärtsilä 6L20 diesel engines, each rated 1,200 kW at 1,000 rpm driving Rolls Royce US 155P14 controllable pitch Z-drive units with 180-cm diameter propellers. The electrical plant consists of three Cummins diesel generator sets that each produce 150 kW of power. Robert Allan says the cooling systems were improved over previous vessels based on Tianjin Port’s experience and input from Wärtsilä.

On the deck there is equipment for ship assist and harbour towing. These tugs each have a Karmoy hydraulic hawser winch, spooled with 180 m of line on the drum. They have a pair of independent Karmoy hydraulic windlasses on the bow and a towing hook on the aft deck.

Jin Gang Lun 31 and Jin Gang Lun 32 meet Chinese Maritime Safety Administration requirements for crew cabins. They have accommodation for an operating crew of 10 people, including a masters’ cabin on the main deck, a chief engineer’s cabin and two double crew cabins in the lower accommodation deck. In addition, there is a pilot room for four seated people, a galley and washroom.

Ship-handling fenders on these tugs include a tier of hollow cylindrical fenders with an outside diameter of 700 mm and inside of 350 mm. Plus a tier of 600-mm outside diameter cylindrical fenders at the forecastle deck level and W-block fenders below the main deck level.

There is one tier of 500-mm outside diameter cylindrical fendering at the stern and 400-mm D-fenders along the sheer lines of main deck and forecastle deck. Additional fendering in the form of tires are arranged along bow, stern and deck sheer.

 

Jin Gang Lun 31 and Jin Gang Lun 32 particulars

Owner: Tianjin Port

Builder: Zhenjiang Shipyard

Designer: Robert Allan

Type: ASD harbour and pilot vessels

Class: CCS - i-Ship, Ice Class B

Length, oa: 40 m

Beam, moulded: 11 m

Maximum draught: 3.86 m.

Bollard pull: 36 tonnes

Free running speed: 14.5 knots

Main engines: 2 x Wärtsilä 6L20, rated 1,200 kW at 1,000 rpm

Propulsion: 2 x Rolls Royce US 155P14 drives

Accommodation: 10 people