TOWING / TAKEN IN TOW

TOWING / TAKEN IN TOW. .

Towing equipment and tools. Methods of towing disabled ship. Emergency towing arrangement. Contents of the emergency towing booklet. Procedures for towing in good and rough weather conditions. Calculation of bollard pull and towing speed prior towage. Communication ..

[Audio] REQUIREMENTS FOR ARRANGEMENTS & COMPONENTS In accordance with Resolution IMO A535( 13) & MSC. 35( 63) The emergency towing arrangements should be so designed as to facilitate salvage and emergency towing operations on tankers primarily to reduce the risk of pollution. The arrangements should at all times be capable of rapid deployment in the absence of main power on the ship to be towed and easy connection to the towing vessel..

Strength of the towing components: 1. Towing components as specified in 2.2 for strength should have a working strength of at least 1,000 kN for tankers of 20,000 tonnes deadweight and over but less than 50,000 tonnes deadweight and at least 2,000 kN for tankers of 50,000 tonnes deadweight and over(working strength is defined as one half ultimate strength). The strength should be sufficient for all relevant angles of towline, i.e. up to 90° from the ship’s centerline to port and starboard and 30° vertical downwards. 2. Other components should have a working strength sufficient to withstand the load to which such components may be subjected during the towing operation..

Towing Components The major components of the towing arrangements should consist of the following:.

Fairlead Chafing Chain Storage Box AFT Pick-Up Gear Towing Pennant Strong Point Storage Drum FORWARD Towing Pennant Fairlead Triangle Plate Strong Point Chafing Chain.

Pick Up Gear Box: 1. The box containing the pick-up gear is to be fitted on the rail of the ship, close to the fairlead and the box contains the following items. Pick up chain – fitted with a connecting link for attaching to the shackle passing through the cable thimble. Stainless Steel Pickup Buoy with light Polypropylene Pickup Cable Additional equipments also includes but not limited to; Pick Up Line Messenger Line Withdrawal Line Retrieval Wire Pull Back Bit Buoy.

Fairleads: 1. Fairleads should have an opening large enough to pass the largest portion of the chafing gear, towing pennant or towing line. 2. The fairlead should give adequate support for the towing pennant during towing operation which means bending 90°to port and to starboard side and 30°vertical downwards. The vending ratio (towing pennant bearing surface diameter to towing pennant diameter should be not less than 7 to 1.) 3. The fairlead should be located as close as possible to the deck and, in any case, in such a position that the chafing chain is approximately parallel to the deck when it is under strain between the strongpoint and the fairlead..

Location of strongpoint and fairlead: The bow and stern strongpoint and fairleads should be located so as to facilitate towing from either side of the bow or stern and minimize the stress on the towing system. Chaffing Chain: 1. The Chafing chain is a STUD LINK chain used for the standard connection between the strongpoint and a standard pear-shaped open link allowing connection to a standard bow shackle. 2. The chafing chain should be stowed in such a way that it can be rapidly connected to the strong point. 3. The chafing chain should be long enough to ensure that the towing pennant remains outside the fairlead during the towing operation. A chain extending from the strongpoint to a point at least 3 m beyond the fairlead should meet this criterion..

Special end Link 95mm dia Enlar Lin Shackle Mooring havvser 170 370 Thimble 267 mm 130 327 Type Not less than 24 cornmon links (24mm x 304mm = 7296mm) 96mm dia hole : Oblong plate 170 mm : 100 Pick up rope 76mrn stud link chain Chain tested and inspected in accordance With IACS W22 0b Iona late. material: cast steel BS EN f0393:200S or plate steel material to BS EN 10025-1 :200a (or equivalent) SWL PR load 59T BR load 84T Shackle in material: BS ENI 826M aoPGr•ade U or equivalent Shackle bow, material: BS EN 60SM 36 Grade T or equivalent SWL42T PR load BR load 84T 70mm MBL tonne 611.7 497.8 53mm dia hole 76mm • mm 350 mm Taper pins 96 102 51 mm 51 mm Size 76mm 76mm Grade per IACS W22 SWL tonne 250 200 The number and size Of Chafe chains used should be determined by the terminal operator after an analysis Of the maxirnum mooring loads. If necessary, weak links or quick release devices should be incorporated into the mooring system..

Towing pennant: 1. The towing pennant should have a hard eye-formed termination allowing connection to a standard bow shackle. 2. Towing pennants are connections used to easily connect the apex of the ship to the tugboat’s towing line the Apex side is connected with the chain pennant and the other side that is the chain pennant is connected to towing wire. 3. Its length should be two times the lightest seagoing ballast free board at fairlead + 50m..

Smith Bracket Storage Box for Towing Pennant Chock Stainless Steel pickup Buoy with light Chock Roller Pedestal Towing Pennant.

Method of Towing a disabled ship. General 1.The Master of the ship should determine the towing pattern in consultation with the towing company. 2. The ships should be towed from the bow as far as possible. If it is not possible to tow from the bow for some reasons such as grounding, collision, towing from the stern may be selected as an alternative. 3.Following circumstances are to be taken into the Master’s account. a) Ship’s position b) Availability of the propulsion system c) Direction and rate of drift d) Distance and estimated time to any possible groundinglocation e) Weather and sea conditions f) Short-term marine forecast for the area of the incident.

Pattern 1-F (Towing from the bow): Use a hawser or a wire rope and a bollard.

Pattern 2-F (Towing from the bow) Use wire ropes or chains and two bollards in order to distribute the towing force..

Pattern 3-F (Towing from the bow) Use hawsers of the ship..