Port tugs (harbour tugs)

01

Size the bollard pull, propulsion and dimensions

Damen's ASD Tug 2811 product sheet lists towing, mooring and escorting functions with Bureau Veritas Escort Tug class (bollard pull 60 t, maximum steering force 58 t, maximum braking force 70 t, maximum escort speed 10 kn); length overall 28.57 m, beam 11.43 m, draught aft 4.65 m, displacement about 550 t and 299 GT; bollard pull ahead 60.0 t and astern 55.0 t; speed 13.0 kn ahead; two Caterpillar 3512C engines totalling 3806 bkW (5104 bhp) at 1800 rpm driving two Rolls Royce US 205S azimuth thrusters with 2400 mm propellers; 67.8 m³ fuel oil; accommodation for a maximum of 8 persons. [1] Damen's web page for the same design gives bollard pull astern as 57 t, so confirm the figure for the hull on offer. [1]

The larger ASD Tug 3212 sheet lists Escort Tug class at 85 t bollard pull (steering force 75 t), length 32.70 m, beam 12.82 m, draught aft 5.90 m, displacement 800 t, bollard pull ahead 82.4 t and astern 77.4 t, 13.5 kn, two Caterpillar 3516C totalling 5050 bkW at 1800 rpm, Kongsberg Maritime US 255 P30 FP thrusters with 3000 mm propellers, 148.3 m³ fuel oil and accommodation for 10 (optionally 12) persons. [2]

Voith describes the Voith Water Tractor, built around the Voith Schneider Propeller, as able to go from full speed ahead to full speed astern in three seconds; its RAVE tug places two VSPs in the keel, and the Carrousel RAVE Tug carries its towing winch on a ring rotating freely around the deckhouse. Reference tractor tugs include Eitan (30.25 × 13.0 × 6.7 m, 2 × 2,525 kW, 2 × VSP 32RV5 EC/265-2) and Rawabi Liberty (31.15 × 11.2 × 5.71 m, 2 × 1,765 kW). [3]

Editorial calculation: bollard pull in kN ≈ tonnes-force × 9.81, so 60 t ≈ 589 kN and 82.4 t ≈ 808 kN; 3806 bkW ÷ 60 t ≈ 63 kW per tonne of pull for the 2811 and 5050 bkW ÷ 82.4 t ≈ 61 kW per tonne for the 3212.

Give the builder the port and ship sizes served, required bollard pull ahead and astern, escort duty (steering and braking force, escort speed), propulsion type (ASD or VSP), maximum length, beam and draught, engine emission tier, class society and notations, towing winch and hook requirements, fendering, fire-fighting notation, wheelhouse controls, crew number and delivery date.

02

Specify towing gear, fendering and fire-fighting

On the 2811 sheet the fore towing winch is a hydraulically driven double drum with 39 t pull up to 9.5 m/min, high-speed pull up to 32.5 m/min and 150 t brake; an optional aft two-speed winch with spooling device pulls 38 t with 150 t brake; optional towing hooks are SWL 65 t. Fendering is D-fender at the sides, cylindrical fenders at the transom corners and a cylindrical and W-block bow fender. The optional fire-fighting set uses main-engine-driven pumps of 1200 or 2400 m³/h or water spray, with 1 × 1200 or 2 × 1200 m³/h water/foam monitors, under the optional Bureau Veritas Fire Fighting Ship 1 notation, with or without water spray. [1] The 3212 lists a 200 t brake on its two-speed double-drum towing winch, an aft towing hook of SWL 100 t, and nine heavy fender tyres on the fore ship in addition to side, transom and bow fenders. [2]

Türk Loydu's rules for fire-fighting ships define FF1 as equipment for fighting fires in the initial stage and rescue in the immediate vicinity, and require for FF1: 2 water monitors of 1200 m³/h each, length of throw 120 m (horizontal distance from monitor outlet to centre of impact), height of throw 45 m (measured at least 70 m from the ship), 1–2 pumps totalling 2400 m³/h, a water spray system, 4 fire hydrants on each side, 4 firemen's outfits and 24 h fuel supply with all monitors running. [4]

For the monitors themselves, the same rules require an approved type delivering a concentrated jet, at least two with permanently fitted controls for solid or spray jet, fastening designed for recoil and sea loads, seawater-resistant material, and horizontal traverse of 45° to each side. Monitors and valves are remote operated from a safe station with visibility, with local operation also provided; at least two independent control systems so a single failure disables no more than 50% of monitors, and lost function restored within 10 minutes. The ship must hold position with all monitors running using no more than 80% of propulsive power, demonstrated on sea trials. [4]

Editorial note: FF1 is Türk Loydu's notation; ask the builder which class society's fire-fighting notation the tug will carry and for that society's monitor, pump and test requirements.

03

Joystick towing mode, split control stands and wheelhouse equipment

Kongsberg's Joystick M50 fact sheet describes a joystick operator station with a joystick and touchscreen, listing automatic heading, station-keeping and a towing mode (the sheet splits functions into standard and optional, so confirm which are included); the towing mode lets the operator step the along-ship force applied during towing from the touchscreen; its thrust allocation converts force demands into thrust and azimuth setpoints for each propulsion unit. The 12-inch panel is rated IP22 (IP56 flush mounted) for −25 °C to +70 °C, and the 35 kg control cabinet IP54 for −15 °C to +55 °C. [5]

Voith notes split control stands developed for longer escort distances on Skeg First tractor tugs. [3] The Damen sheets list wheelhouse navigation and communication equipment — radar, autopilot, satellite compass/GPS, echosounder, VHF, AIS, Navtex and remote monitoring readiness — with ECDIS optional on the 3212. [1] [2]

When requesting quotations, ask each builder for the general arrangement, class certificates, bollard pull trial report, winch and hook certificates, fire-fighting test records and the wheelhouse console layout.

04

Thrusters, bridge console, joystick, towing winch, fenders and fire monitors

The winch, hook and fender values repeat the Damen ASD Tug 2811 sheet and the monitor values Türk Loydu's FF1 rules; the console rows come from Kongsberg and Voith.

05

Damen ASD 2811 and 3212 figures, field by field

Where a row gives two values, the first is the Damen ASD Tug 2811 and the second the ASD Tug 3212; operating temperature has no vessel figure in any source reviewed.

06

Send the duty, dimensions and outfit together

Paste it into your enquiry below or into an email to a maker, then replace every bracket.

Duty: [ship sizes; berthing; escort speed]
Bollard pull: [t ahead; t astern]
Propulsion: [ASD; VSP; power]
Limits: [LOA; beam; draught]
Towing: [winch pull; brake; hook SWL]
Fendering: [bow; sides; stern]
Fire-fighting: [notation; monitors m³/h; water spray]
Bridge: [thruster levers; joystick; navigation]
Class and crew: [society; persons]

See manufacturer records Send an enquiry through CNFX