Tugs and tows a practical safety and operations guide. It is reminded that this test is inten ded to determine the static bollard pull of the vessel in order to estimate. However, the term bollard pull has developed three different meanings, and it is important to know which intended meaning is being used. This procedure is primarily intended for tugs supply vessels and other vessels of. The bollard pull of a tug is the force it exerts at zero forward speed, in calm water conditions, with the engine working at its full power 100% mcr.
Detailed information is available in the anchor handling manual. Whether these figures were theoretical or the results of rudimentary bollard pull tests is unclear as. Various aspects of bollard pull tests and analysis of test. Bollard pull is the static force exerted by a tug at zero speed on a fixed line. Unlike ground vehicles, the statement of installed horsepower is not sufficient to understand how strong a tug is this is because other factors, like transmission losses, propulsion type, propulsion. The procedure for performing re evaluation bollard pull tests at part load is included in appendix 3. This figure is not accurately determinable by mathematical methods, therefore it must be evaluated for each tug by a bollard pull test. Almost always, a test involves affixing a line to a shorebased bollard and ramping the rpms of the engine to full throttle, typically in ahead and astern conditions. Values provided by manufacturers can vary due to lack of standards for testing. Bollard pull certification procedures guidance information, 1992 4. International standard for bollard pull trials download. Definition of bollard pull the bollard pull of a vessel is defined as the tractive force of a tug, which can be expressed in metric tonnes tonne or kilo.
International standard for bollard pull trials page 4 31 1 definitions 1. This bollard pull trial code is established to define the procedures of. Ship repair services also include the bollard pull test which measures the pulling or towing power of watercrafts conducted by certified experts. What is bollard pull test and requirements for the bollard. Sustained bollard pull is the mean val ue of the pull during a 5 minutes test. Bollard pull is a direct measurement of the ability of the vehicle to pull on a cable. The procedure to be followed is described in part 2. Recommended swl, load position, safety factor and test load fitting swl load position line position safety factor on yield test load notes double bollards per iso 39 single rope maximum loading 1. The safe working load of the test equipment, fittings and any connection points ashore shall be at least 10% in excess of the designed maximum continuous static bollard pull of the vessel. Schottel has already invested a lot of time and manpower to improve the understanding of the factors which influence the performance of ducted propellers during bollard pull. Most articles that i have found referencing bollard pull discuss how much bollard pull is required for towing a specific type of vessel. Purpose of procedure the purpose of the procedure is to ensure consistency of methodology and the acquisition of correct results for the propulsion test and its special cases bollard pull and trawl pull test bollard pull is the static force exerted by a.
The following testing procedures should be adhered to. Bollard pull, like horsepower, is a selling point for tugs and is sometimes overstated. Propulsionbollard pull test effective date 2017 revision 05 updated edited approved propulsion committee of the 28th ittc 28th ittc 2017 date. International standard for bollard pull trials download vessel. Aspects of the design procedure for propellers providing. Proposed test program should be submitted prior to the testing. This excel sheet helps you calculate the required bollard pull of a tug used for towing a barge how is the excel sheet organised. Note that according to the vmo rules the bollard pull certificate and the test.
The methodology that was developed inhouse is based on the transmission of vibration and sound through the structure allowing us to pinpoint any errors. If the readings are recorded at 30 seconds intervals, sustained bollard pull is the mean value of these readings during a 5 minutes test. Download international standard for bollard pull trials. International standard for bollard pull trials v1 2019. The capacity of tugs is measured by their rated bollard pull.
Practical bollard pull tests under simplified conditions are conducted for human powered vehicles. En iso 4624 pulloff test for adhesion november 2019 106. Bollard pull test procedure ships telemetry scribd. The first method is based on dnv rules for marine operations. It is defined as the force in tons or kilonewtons kn exerted by a vessel under full power, on a shoremounted bollard through a towline, commonly measured in a practical test but sometimes simulated under test conditions that include calm water, no tide, level trim, and sufficient depth and side. The following guidance notes apply to the bollard pull test of any towing vessel which the surveyor is requested to approve or attend. I am looking for a simple spreadsheet or other program that can provide a rough estimate of the bollard pull capacity of a towing vessel without having to actually conduct a bollard pull test. The actual bollard pull trail is carried as follows. Various aspects of bollard pull tests and analysis of test results arun kr dev. A bollard pull trial is a full scale test with a vessel to determine the horizontal towline force. Tug owners whose tugs have been tested usually provide a copyof the certificate attesting to the bollard pull figure. The bollard pull test should be held in a location of reasonably sheltered from wind, current, tide and wave. Bollard pull overview international marine consultancy.
Maximum static bollard pull is the highest 30 second value read during the test. Test procedure bollard pull tests should be carried out under similar conditions to facilitate comparison with results obtained at different testing establishments. Marin performs, analyses and reports bollard pull trials according to this standard which is set up in collaboration with several class societies abs, bv, lr. Zahalka, association of hanseatic marine underwriters bollard pull is, the tractive force of a tug, expressed in metric tonnes t or kn. Leps 150mton wireless bollard pull test system configuration page 2 of 8 bollard pull test procedure asl shipyard 5.
Actual bollard pull can only be measured in full scale, and is performed during socalled bollard pull trials. Bollard pull tests bollard pull trials are conducted in order to determine the static pull that a tug is able to employ in operating conditions. In exceptional cases when neither method of bollard pull testing described in. Tug and tows a practical safety and operational guide i 3 chapter 8 towing operations 30 bollard pull bp 30 bp calculation 31 pivot point 32 position of tug and interaction 33 girting, girding or tripping ggt 36 gobgog wire or rope 40 emergency quick release systems for towline 42 the effect of wind 42 the effect of current 42. The bollard test can be done in a test tank of any size, but very small containers may set up a circular flow which can give an inaccurate force reading. The excel sheet provides four different methods for calculations. Ittc recommended procedures and guidelines propulsionbollard pull test. Documentation of bollard pull documentation of all towing vessel equipment, ref.
Recommended swl, load position, safety factor and test load. Bollard pull test is carried out by steaming into a towrope which is fixed ashore and connected to a measuring device, successively with three different performance. Propeller design optimization for tunnel bow thrusters in. Sustained bollard pull is the mean value of the pull during a specific time period 5 to 10 min. The following guidance notes apply to the bollard pull test of any towing vessel which the. Bollard pull test procedure ships telemetry free 30. Maximum bollard pull is achieved with the cable right astern, rudders amidships and a further reduction in bollard pull must be allowed for should the angle of the cable lead other than right astern. Environmental conditions wind speed, current, trial procedures. Bollard pull tests sometimes are performed after major engine overhauls. The smartest bollard test the bollardscan tm is a unique way to establish the reliability of the bollard and its foundation. Rules for the towing survay of barges and tugboats. R ule c ha nge n o t i c e 2014 rule change notice 2014 the effective date of each technical change since 1993 is shown in parenthesis at the end of the. Scribd is the worlds largest social reading and publishing site.
Right through to the late 1960s, tug owners were describing their tugs by shaft power, but by the end of that decade they were advertising the tugs bollard pull as well. Keeping in mind that bollard pull test results have been determined at 0 speed of the tug. Rating is available when the video has been rented. International standard for bollard pull trials 2019 pdf marin.
Bollard pull test trial site and vessel requirements. And whether it still meets the design requirements of the structure. Bollard pull a hydrocomp technical report report 110 overview bollard pull is a term often used to describe the pulling capability of towing vessels. Due to the dynamics of speed and current the force on the line can, at peaks, easily be much higher than the static. Request pdf various aspects of bollard pull tests and analysis of test results the static force exerted on a hawser at zero ship speed by a vessel, otherwise known as the bollard pull, is one. Based on the research carried out in the project the procedure.
Theoretical and experimental measurements of bollard pull with emphasis on. Calculating bollard pull capacity for a vessel boat. The term bollard pull is used as a term referring to the total amount of thrust that a boat or ship can generate and sustain during a test for which the vessel is secured to a. If wind gusts causes the vessel to yaw significantly the test should be. Bollard pull is a conventional measure of the pulling or towing power of a watercraft.