How to calculate bollard pull from horsepower By calculating the Bollard Pull, marine engineers can ensure safe and efficient maritime operations. Simply put, it measures the maximum force a ship can exert when stationary in the water - essentially our equivalent to horsepower or torque in land vehicles. 43 times BHP 500SHP~526BHP 526^0. Fast, accurate, and simple for students, professionals, and everyone. Bollard pull is our marine industry's standard measurement for a vessel's pulling capability. The power output is measured by performing Mar 17, 2020 · The equation to calculate horsepower is simple. load (N, lbf) friction coefficient angle where the rope is in contact with the pole (degrees) Minimum requirements for towing gear The table below shows industry general guidelines for matching the size of the towed barge to the horsepower of the tug. Apr 9, 2013 · Hi everyone! I have developed an excel sheet which can be used to calculate the required Bollard Pull for towing a Barge. Generally Apr 24, 2017 · For tug boats, this parameter is called "bollard pull", i. A 500SHP tug can expect to pull an average load at 1. Bollard pull is the most commonly used measure of ship-assist tugs performance which have propellers optimized for maximum thrust at close to zero speed. 6092 drawbar Power to 746 W 746. The user must fill one of the two fields and the conversion will become automatically. 5 tons pull per 100 horsepower for a propeller fitted with a nozzle. Bollard Pull calculation is essential and one of the most commonly performed tests in marine towing operations to determine the maximum tractive force Dec 23, 2023 · Join this channel to get access to perks: / @simpleandbasiccalculation In this video, we dive into the fundamentals of bollard pull calculation, a critical aspect of ship towing operations. The value of bollard pull is considered critical as it defines the functionality and performance of the vessel. It provides definitions for important concepts like Jul 9, 2010 · There are standard procedures for calculating bollard pull (normal sizing method for tugs) for a given towing job. Yes, the calculator can be used for both marine and land-based towing operations, as long as you input the appropriate values for bollard pull force and efficiency pull factor. It outlines the key steps as: 1) Determine environmental conditions (open ocean or benign), 2) Calculate wind, wave and current forces on the vessel, 3) Add the forces to get total force, 4) Get tug Excel Spreadsheet for Bollard Pull Calculations (Barge) - A spreadsheet to calculate the required bollard pull barge towing tug. Oct 2, 2018 · The bollard pull was also far less than calculations and thumbrules from calculating on ships bollard pull. Some props in thruster/nozzle configurations will get ~40 up to ~60 with tight tolerancing. The combination of motor and propeller that gives the most thrust is often desirable, but other factors, such as amperage draw, may limit Bollard Pull - Free download as PDF File (. Now when you arrived at what is the available bollard pull capacity of the tug, the second stage is to Oct 24, 2021 · Hello all Can you help me to calculate the required engine power for tug boat with 40 tons Bullard pull? the type of propeller will be ASD is there Feb 23, 2022 · English Carrello Il tuo carrello è vuoto. These estimates can be made by the use of charts derived from polynomial expressions of This app uses data collected by the user to calculate the tug's power and bollard pull required to push a barge at a specified speed and environment. times 1. 46 m. Jan 27, 2014 · MT-01 Bollard Pull Calculations for Barge - TheNavalArch Excel Spreadsheet for Bollard Pull Calculations (Barge) A spreadsheet to calculate the required bollard pull to Tow a Barge. How do you calculate bollard pull from horsepower? - Answers Subjects > Science > Engineering In order to calculate what the bollard pull of the tug should be for a towed barge with a displacement Δ and dimensions stated the following formula has been issued by Transport Canada Publication (TP 11960 E of 1995) as a guide. With ~75% rated Bollard pull is crucial for tugboat efficiency, typically aimed at 15 kS per delivered horsepower. Largest ship under consideration is Bollard Pull Calculator (Excel Engine) Step 3: The measured bollard pull is compared with the original performance curve of the tug. Nov 20, 2017 · I am designing a tug with 2 *180 hp engine , length 8 m, breadth 3 m, depth 1. ) 100 SHP=1 T BP 1 HP = 746 W = 0. In order to certify a ship-assist tugs as fit for service, it’s power output must be measured. No port is the same and tug requirements differ from port to port. Feb 4, 2017 · Bollard Pull Calculations for Towing Operations – an Introduction Part I – Calculating the required Bollard Pull (BP) (Click here for Part II) SECTION A – INTRODUCTION Bollard Pull calculation is one of the most frequent calculations performed in marine towing operations. By calculating the Bollard Pull, marine engineers can ensure safe and efficient maritime operations. It provides empirical values for determining bollard pull based on the type of towing operation. Two power sources: one is a 180WattHour lipo battery only for the 25 minute endurance race. 1 horsepower ≈ 0. It explains that the Admiralty Formula is useful when towing is in the same direction as the axis of the towed ship. For example; The engine power of the tugboat named TDİ Kızkulesi, which has a nozzle system Schottel propeller and serves in İzmir Port, is 4200 BHP. Can the towing force calculator be used for any type of vessel? May 31, 2011 · For the bollard pull, you can use the approximate method from Dave Gerr's "The Propeller Handbook". For most "large" standard series props it will be between 30 to 35 lbs per hp delivered. The Bollard test can also be run with multiple motors and multiple propellers to determine maximum overall thrust. The bollard pull calculation formula is as follows. The document outlines the standard calculation process, which involves determining the environmental conditions, calculating The document discusses various formulas for determining the bollard pull and power requirements for tug boats. the force that can be applied via a tow rope when the tug is stationary. What we have: Motor rating: 500W, 467RPM loaded ( it's got a 6:1 reduction gear built in ). Estimation formulas are provided to A 20 degree list on > ONLINE Calculator - PT pull certificate for the tug be! Quora < /a > 09/03/2012 6:48 AM of the pull from horsepower < >! Out this gives an electric horsepower of 1. It discusses that bollard pull calculations determine the size of tug needed to safely tow a vessel. Applying this formula to a sample barge with a displacement of 5535 tons towed at 6 knots estimates a minimum bollard pull of 29. It covers: 1) Calculating the total environmental forces on the vessel from wind, waves and currents. The bollard pull is shown in MT and required Power of the tug is in HP and kW. What is a bollard pull test? As opposed to ground vehicles, the horsepower rating of a watercraft engine is insufficient determining how powerful a ship-assist tug is. Specifically, a Bollard test measures the thrust of different propellers mounted on a single motor. Maximum bollard pull is the value achieved when the engines are running at full load and can only be 1. It discusses how to estimate the maximum safe towing speed for a vessel in a given sea state. The Maximum Bollard Pull, also called “Static Bollard Pull,” is the maximum recorded tension achieved shortly after the test’s commencement over a period of approximately one minute. Bow Thruster of 5000 HP = 3730 KW = 50 tons Bollard pull. It is the amount of force exerted by the tugboat while pulling or pushing a load. Versus Power | Physics Forums < /a > placed on bollard pull requirements figures on already. A bollard pull test must be carried out because it examines the vessel’s maximum power against static objects, such as docks or other ships. Any simplistic calculation will over-predict bollard pull, making for an uncomfortable bollard pull test for everyone involved. Towing operations involve the pulling of a vessel (it can be a barge, ship or an offshore structure) using another Feb 19, 2020 · Web link to free download the mobile application "Bollard Pull Calculation For Marine Pilots”; Bollard Pull Calculator for Android Bollard Pull Calculator for iOS Important note: Please note that data provided by the application are based on theoretical calculations. It is essential for ship design, port navigation, and towing operations. Feb 19, 2020 · A handy and simple tool to determine in a minimum time what is really needed as tug assistance, is the Bollard Pull Calculator which calculates in an approximate way the total required tug power Mar 12, 2025 · Ship Bollard Pull Calculation Ship Bollard Pull is an integral concept in marine engineering, playing a vital role in towing and manoeuvring of ships and other maritime structures. Oct 12, 2008 · Can anyone provide me with info on calculating the required bollard pull of a harbour tug. Bollard pull is defined as the measure of a vessel's towing capability, represented by the tension in the towing wire during trials, with three specific types: maximum bollard pull, steady bollard pull, and effective bollard pull, each varying based on duration and conditions of the trial. 1 Bollard P Pull Testt Descripttion Bollarrd pull is the z zero speed pu ulling capabiliity of a vessel (i. Bollards are safety-critical components, and ESC strives to provide bollards with superior service life and resistance to physical and corrosive environments. 6 and 1. The methodology involves determining the environmental forces at different speeds, plotting tug performance curves, and finding the intersection which is the limiting towing speed. It is defined as the force (usually in tonnes -force or kilonewtons (kN)) exerted by a vessel under full power, on a shore-mounted bollard through a tow-line, commonly measured in a practical test (but sometimes simulated) under test conditions that include calm water, no tide, level trim, and sufficient Nov 1, 2024 · The developed methodology for calculating the traction power (bollard pull) of tugboats allows us to determine the required traction force of tugboats in advance with sufficient accuracy, achieved by assessing the specific parameters and environmental conditions of the vessel served by tugboats. 08 and divided by 100 for a fixed pitch propeller with a kort nozzle, brake horsepower multiplied by 1. Bollard p pull tests are a also sometimes performed d after major e engine overhauls. Vehicle weight should include not only the vehicle, but also the driver, the passenger, and anything else of significant weight. It should deliver 400watts ( via a throttle control and watt-meter ) for 28 minutes. This document provides guidelines for conducting a static bollard pull test to verify a vessel's towing capability. https://thenavalarch. It discusses key concepts like bollard pull testing, towing efficiency, and environmental forces on towed vessels from wind, waves and currents. Approved Bollard Pull for tugs over 10 years old, without a bollard pull certificate less than 10 years old, may be the greater of: • The certified value reduced by 1% per year of age since the BP test, or • 1 tonne/100 (Certified) BHP reduced by 1% per year of age greater than 10. The vessel then propels itself forward at maximum thrust, and the tension measured in the towline shows the total thrust achieved. so its unit is obviously N or KN ; but it is also measured in tonnes . While most tractor-style tugs designed for ship-assist work and tanker escorting have long been subjected to bollard pull testing, new rules from the American Bureau of Shipping (ABS A Bollard Pull Calculator é uma ferramenta útil para a indústria marítima, fornecendo cálculos precisos para forças de reboque. Nov 10, 2019 · Bollard Pull is a measure of the pulling power of a vessel, comparable to the horsepower rating of conventional vehicle engines. This paper focuses on how we use (or misuse) this information, its validity and its relevance to real life towing operations. Specalized wheels can get up to 200 lbs thrust per Bollard pull is our marine industry's standard measurement for a vessel's pulling capability. 746 KW So A bow Thruster of 1000 HP = 746 KW = 10 tons Bollard pull. The test is to be monitored by ABS surveyors and equipment must be calibrated, with two surveyors required unless a continuous recording device is Tug power increases continuously and tugs with a bollard pull of 70 tons can be found already in a number of ports or are under construction, while harbour tugs with a bollard pull of 100-120 tons are already considered. Aug 17, 2025 · This app uses data collected by the user to calculate the tug's power and bollard pull required to push a barge at a specified speed and environment. It discusses that bollard pull calculations determine the minimum tug size required to safely tow a vessel. It provides a formula that takes into account the displacement of the tow, towing speed, wind resistance, width and height of the tow, and other factors. There are ways to measure shaft torque, thrust, and rpm; but those are usually only done as contract deliverables. From the top of my head I can think of, inertial force, drag (current and wind), mean drift additional drag to name some. The result of the achieved traction force of the tug at different performance-levels of propulsion will be certified and an of Bollard Pull certificate will be issued. This tool converts horsepower to tons (hp to ton) and vice versa. 212 tons. Note this shaft horsepower (shaft torque*shaft rpm) delivered, not rated hp. The key factors in bollard pull design are installing the largest possible propeller Previous studies have focused on how we measure or calculate bollard pull. In the Part I we saw how to calculate the required Bollard Pull. It is a practical application of engine power and propeller efficiency and is essential for tugboats, salvage operations, and offshore industries. Apr 16, 2024 · The Bollard Pull Calculator is a handy tool for the maritime industry, providing precise calculations for towing forces. 125 and divided by 100 for a This document introduces the concept of bollard pull calculations for towing operations. 96) - D is the propeller's diameter in inches. This is due to two things – propellers accelerate water as they spin so they Aug 18, 2014 · Well as I suspected my reply has got you answers from the very gentlemen who have helped me learn about boat design. 076 Aug 9, 2025 · To measure bollard pull, we secure the vessel to a fixed pier bollard (those strong metal posts you see on docks) and use specialized load cells to calculate the tension generated in the line when the engines run at full power. Bollard pull is a conventional measure of the pulling (or towing) power of a watercraft. Jun 17, 2024 · A handy and simple tool to determine in a minimum time what is really needed as tug assistance, is the Bollard Pull Calculator which calculates in an approximate way the total required tug power for ships in various conditions of wind and current. 3) The steps for performing bollard pull calculations, which Sep 11, 2023 · Bollard Pull Test is the trail performed to determine the static pull or zero speed pulling that a tug can employ in operating conditions; in another term, the bollard pull test is the tractive force of a tug expressed in metric tons (T) or KN. Oct 3, 2024 · This calculator simplifies the complex calculations of horsepower, making it easier for automotive enthusiasts, engineers, and students to estimate the power output of vehicles and engines. 33kts. Jan 1, 2021 · support shuttle tanke r from the FSO. Select the right tug for your barge and also find out the limiting towing speed during the voyage using this simple calculator. It can be defined as the thrust that is developed by the propulsion systems of any vessel when it has a zero speed in the forward direction. It is simply the theoretical thrust achieved at zero speed of advance and full engine RPM. Bollard Pull Calculations For Towing Operations | PDF | Tugboat | Ships. 67 where: - T is the bollard pull, in pounds - SHP is the engine shaft horse power (calculate it as brake horse power, BHP, times 0. Sep 24, 2023 · This app uses data collected by the user to calculate the tug's power and bollard pull required to push a barge at a specified speed and environment. The estimated bollard pull, towline breaking strength and size of the towline are in accordance with the American Waterways Operators (AWO) Responsible Carrier Program minimum requirements for towing gear. more Understanding Bollard Pull Bollard pull is a key metric used to measure the towing capacity of a tugboat. It describes the key definitions like maximum, steady, and effective bollard pull. To measure bollard pull, we secure the vessel to a fixed pier bollard (those strong metal posts you see on docks) and use specialized load Bollard pull rating This is the traditional calculated measure of merit that was used as a “rating” for tugboats. The maximum speed is where the Jan 26, 2021 · This document provides an overview of bollard pull tests, which are used to determine the maximum tractive force of tugs. At zero boat speed, propeller slip will be high if testing a high pitched prop with high revolutions, so for a TUG operating at low speeds and needing maximum bollard pull, the pitch (and therefore its slip) will be kept as low as practical but given enough pitch to absorb maximum available horsepower. Towing operations involve the pulling of a vessel (it can be a barge, ship or an offshore structure) using another Jun 2, 2024 · The Bollard Pull Calculator Yaylali has developed calculates in an approximate way the total required tug power for ships in various conditions. Bollard pull is primarily used for measuring the strength of tugboats. In short: Bollard Pull Calculations for Towing Operations – an Introduction Part I – Calculating the required Bollard Pull (BP) (Click here for Part II) SECTION A – INTRODUCTION Bollard Pull calculation is one of the most frequent calculations performed in marine towing operations. Also any info referencing justificaton in the choice of using either a Voith-Schneider or Azimuth propeller. Bollard pull is usually measured in tons or kilonewtons, and it is a crucial factor in determining the overall towing capacity of the tugboat. Key requirements include having calm sea conditions, a minimum water depth, and taking the average pull measurement over 3-5 minutes. Find out everything you wanted to know about bollard pulls inside the article. Nov 28, 2009 · Ref : Oilfield seamanship volum 8, page 173. Aug 13, 2022 · In a tugboat with a nozzle (sleeve) propeller system, dividing the horsepower in BHP by 85 gives the pulling power (Bollard Pull) of the tug in tons. txt) or read online for free. It’s usefulness for practical calculations is of little value. Bollard-pull charts offer a reliable method for estimating propeller We are housing highly useful and time-saver apps for the maritime industry, used by thousands of companies globally to carry out their design/operations smoothly. 2) Determining the minimum bollard pull rating for the tugboat needed to overcome these forces, based on the tugboat's towing efficiency. Also provided is a converter for common units of power. Bollard (or Pole) Effort Force Calculator This calculator is based on the equation above and can be used to calculate the effort force in ropes turned around poles or bollards. Note the tug in consideration will probably be used >95% of time for berthing/unberthing ships. Nozzels will increase this 10-20%, props less than ~48" diameter will reduce it 10-20%. Oct 19, 2019 · We are glad to launch a new product - the Bollard Pull calculator (Barge) with Limiting Towing Speed Select the right tug for your barge and also find out the limiting towing speed during the voyage using this simple calculator. É essencial para o projeto de navios, navegação portuária e operações de reboque. 341 horsepower Maximum instantaneous bollard pull is the value achieved during a test pull when the vessels momentum contributes to the load on the test line. Feb 22, 2023 · Just like horsepower is a universally understood unit of power used to measure the performance of road vehicles, the bollard pull is a universally understood unit used to measure the pulling power of ships, mainly tugboats. As we can see above to get power equivalent to a 50 tons tug, we need Bow thruster of 5000 HP. Preliminary design can utilize minicomputers for quick propeller characteristic estimates using experimental data. Online calculation of bollard pull of ships, semi submersible, jackups and other floating structures Engine Horsepower Calculator The following two calculators can be used to estimate the engine horsepower of a vehicle based on the weight of the vehicle, elapsed time, and speed used to finish a quarter mile run. On the odd occasion these movements could be with a 'cold' ship. Bollard pull rating is an abstract (and somewhat academic) state that cannot be achieved in real operation. But in Practice a 5000 HP Bow thruster will be much Bollard pull is a conventional measure of the pulling (or towing) power of a watercraft. The calculations can be certified by Det Norske Veritas (DNV) or for 3rd party surveyors. 25. This document introduces how to calculate the required bollard pull for towing operations. Optimum propeller design includes maximizing diameter and maintaining pitch-diameter ratio between 0. Note that the calculator uses degrees for the turns. For a given environment, it calculates the limiting towing speed possible for the tow This app calculates each of the following components separately and adds them to give the final a bollard pull test and simply apply one of the factors to convert propeller power to bollard pull without ever knowing what the real figure is It is unlikely that this owner will ever select a conservative conversion factor European owners generally report bollard pull in their literature and reputable salvage tug owners generally are able to Bollard Pull Calculations for Towing Operations – an Introduction Part I – Calculating the required Bollard Pull (BP) (Click here for Part II) SECTION A – INTRODUCTION Bollard Pull calculation is one of the most frequent calculations performed in marine towing operations. Bollard pull is calculated by connecting a pier bollard with a towing mechanism on the vessel and computing the force or tension developed in the connection using a load cell or similar component. Bollard pull is a vessel’s pulling power compared directly to the horsepower or conventional vehicle torque. Determining MBP takes place with the maximum engine output, optimum propeller pitch, and during working in still water. it is measured using a load cell or dynamometer . com/software/mar A spreadsheet to calculate the required bollard pull to Tow a Barge. Very useful in Marine Operations Gives 4 different methods to calculate the required Bollard Pull: DNV, OPL, BV and Empirical This app uses data collected by the user to calculate the tug's power and bollard pull required to push a barge at a specified speed and environment. It also covers how to calculate the necessary power when the tug is used for maneuvers, taking In shipping and sea freight, the bollard pull test is critical. Bollard Pull Force Calculator: Enter the values of Bollard Pull Force BF (kiloNewton) & Efficiency Factor EF to determine the value of Towing Force TF (kiloNewton). The thrust developed at zero ahead speed. Feb 24, 2017 · This document is part two of an article on calculating bollard pull for towing operations. So, read this This Concrete Estimator is specifically built for Bollard Installation Cost Estimating. SHP=BHP (approx. It outlines the ideal test conditions and requirements, including water depth, vessel state, environmental factors, test procedures, and data collection. , Ltd as a propulsor of a tugboat, and the full-scale bollard the vessels Mar 17, 2020 · The equation to calculate horsepower is simple. We are at the prop sizing stage of design. Choose to calculate horsepower or torque Horse Power Torque (ft·lbs) Enter the following values to calculate horsepower Torque in foot pounds (ft·lbs) Engine RPM. ESC bollards are designed and manufactured in accordance with various international standards such as BS 6349 Part 4 and PIANC guidelines. Towing operations involve the pulling of a vessel (it can be a barge, ship or an offshore structure) using another Sep 3, 2012 · If I now know the Bollard Pull of a Fixed Pitch Propeller, how should I calculate the Power of it or the other way round Feb 18, 2017 · This is Part – II of the two part article on Bollard Pull calculations. The app also calculates the tugs power and bollard pull required for a storm condition to hold a barge. The usual range is about 1. To measure bollard pull, we secure the vessel to a fixed pier bollard (those strong metal posts you see on docks) and use specialized load Nov 28, 2024 · Once all inputs are provided, the components of required bollard pull are calculated and added up to give the Static Bollard Pull required. During the preliminary design of a tugboat, the use of minicomputers can permit the designer to give a very quick estimate of propeller characteristics such as pitch-diameter ratio, expanded area ratio, revolutions per second, and the thrust and delivered horsepower for the bollard-pull condition. Aug 1, 2018 · The static force exerted on a hawser at zero ship speed by a vessel, otherwise known as the bollard pull, is one of the key performance indicators of Tugs, Anchor Handling Tugs (AHTs) and Anchor Handling Tug Supply Vessels (AHTSVs). I have verified the sheets, but it will be great if you can test the Nov 24, 2012 · Question is, for which condition I will calculate the propeller particulars? 2X600 BHP will give approx. It adds the footing volume and pipe volume. Can anyone help me how to find this vessels bollard pull capacity using any empirical equations? Oct 25, 2022 · To calculate the bollard pull of a vessel, the vessel is anchored to a pier using a bollard. Jun 29, 2025 · Bollard pull is our marine industry's standard measurement for a vessel's pulling capability. It is a practical application of engine power and propeller efficiency and is essential for tugboats, salvage Apr 22, 2020 · Bollard Pull is a measure of the pulling power of a vessel, comparable to the horsepower rating of conventional vehicle engines. A smartphone app has been launched providing marine pilots with a tool to calculate the number of tugs To convert bollard pull to horsepower (HP), you can use the formula: ( HP = \frac {BP \times V} {550} ), where ( V ) is in feet per minute. You get the number either from propeller test or you (rarely, because of the risk involved) measure it directly. Apr 14, 2025 · Coming in a close second is the Far Samson with a bollard pull of 423 metric tons; this was the previous holder of the record and boasts an impressive 41,000 hp. This link is to one such The document discusses calculating the required bollard pull for tugboat towing operations. The document outlines the key factors that affect bollard pull requirements, including vessel size, environmental conditions, and tug efficiency. The app will calculate the required bollard pull and power to push or tow a barge or group of barges in open water or inland waterways (protected waters). Nov 24, 2022 · From the horsepower (BHP) of the tug's machine, the approximate bollard pull value of the tug in question can be calculated. The remaining traction force is named “Continuous Bollard Pull“ or also “Steady Bollard Pull“ and is measured for a period of about 10 minutes. It presents equations and charts derived from experimental propeller data that allow designers to quickly estimate propeller characteristics and the thrust and power needed for bollard pull conditions. If you want to know the required bollard pull for a specific application you need to calculate the sum of external forces for your particular case. This article discusses the bollard pull test and its procedure. To measure bollard pull, we secure the vessel to a fixed pier bollard (those strong metal posts you see on docks) and use specialized load The thrust developed at zero ahead speed. This document provides formulas to calculate bollard pull in tons from brake horsepower for different propeller and nozzle configurations: bollard pull equals brake horsepower divided by 100 for a fixed pitch propeller, brake horsepower multiplied by 1. What is the pulling power of a tugboat? So before we proceed we will again recap on below conversion of power. Bollard pull calculation is calculated using for mula and recommendation from DNV-GL. Here’s a step-by-step guide on how to use Bollard Pull: It is the measure of the traction in a cable, generated by the tug when it is at maximum power in its engines when connected to the tug’s winch or towing hook, a load cell, and a large, sturdy bollard on a pier. This document provides an introduction to calculating the required bollard pull for tugboats engaged in towing operations. My primitive testing shows clearly, that if I buy a cheap scale going to 200 kilograms, i could make these bollard pull measurements quite presise and easy another day. This reduction in the available bollard pull of the tug can be calculated by a factor called ‘interaction efficiency factor’, αint which is a function of the size of the propeller, the length of This document discusses how to calculate the minimum bollard pull requirement for a tugboat towing a barge. For instance, there are rules ofthumb for converting propeller power (SHP) to bollard pull, such as one ton pull per 100 horsepower for a conventional propeller, or 1. Where Bollard Pull Comes In A tugboat’s horsepower is an important rating to determine what a vessel is capable of in terms of pulling or pushing, but the more meaningful measurement is known as the bollard pull. 7kts. To measure bollard pull, we secure the vessel to a fixed pier bollard (those strong metal posts you see on docks) and use specialized load Jan 26, 2012 · My general rule of thumb for bollard pull of a standard B or K series prop is 35 lbs bollard per 1 shp in. Feb 17, 2020 · We're pleased to launch the Bollard Pull Calculator (Ships) with Limiting Speed This Excel sheet helps you calculate the following: 1. You can use our horsepower calculator to try it out yourself. Ideallly, a bollard p pull test is s completed o once the vess sel is built and d is then certiffied by one off the marine c classification societ ties. Description Static Bollard Pull Calculator for Barges – Athwartship What does this App do? This app helps the user calculate the static bollard pull required to HOLD a barge being towed by beam The calculated required Bollard Pull can be used to select the right sized tug for towing a Barge Alternatively, it can be used to check whether a selected tug is suitable for towing a Barge of not The bollard pull of a vessel may be reported as two numbers, the static or maximum bollard pull – the highest force measured and the steady or continuous pull over an interval, for example, 10 minutes. In road vehicles, the torque and speed have a close relationship. There are some formulas we can use for this: Feb 3, 2025 · As a rules of thumb for an approximately conversion from BHP to “t” of the effective available Bollard Pull the following formulas may apply: The resulting values have to be regarded as rough This free online tool gives you instant towing force results based on two main methods: marine towing (bollard pull-based) and trailer towing (friction and axle-based). 15 knots speed, but I need this power to over come the required bollard pull. How to Use the Towing Force Calculator The towing force calculator is designed to be simple and user-friendly. 43 =5. Thus, bollard pull and horsepower can be connected through their relationship with thrust and speed. Nov 16, 2017 · Building a solar/battery powered race boat for a school challenge. It provides options for calculations using three methods: OPL Guidelines, BV Rules and Empirical formula. To estimate the peak horsepower, maximum work output Feb 19, 2014 · bollard pull is the zero speed pulling capacity of a tug . This can help in selection of an appropriate Tug for a tow. The power output of a tug determines the pull or towing force it is capable of applying. The only thing I would like to add is ( from Gerr's book) is average tow speed. pdf), Text File (. Aug 5, 2021 · Bollard Pull is a measure of the pulling power of a vessel, comparable to the horsepower rating of conventional vehicle engines. The towing environmental parameters are then utilised to calculate required pull at different towing speeds, which is matched against the tug’s performance curve to give the limiting towing speed ESC bollards are designed and manufactured in accordance with various international standards such as BS 6349 Part 4 and PIANC guidelines. The newly designed ducted propeller is equipped for “Z-peller” of Niigata Power Systems Co. e. Aug 3, 2008 · Bollard pull, like horsepower, is a selling point for tugs and is sometimes overstated. Bollard pull 1 kw = 1. 87 * ( SHP * D )^0. This tool can be loaded as an app on the smart phone. It also includes formulas to calculate brake horsepower from bollard pull and displacement, as well as a more advanced formula that takes into account wind speed and seas conditions when This free calculator determines horsepower as a unit of power given force, distance, and time. , tug or A AHTS). The document presents formulas and concepts for calculating the power required to tow ships. Required Static Bollard pull of a Tug used for towing a Ship-shaped vessel 2. 5 tons per 100 HP (sorry about the non-SI units!) Oct 3, 2024 · How is the bollard pull force measured? Bollard pull force is measured during a bollard pull test, where a vessel is made to pull against a fixed point (bollard) on land, and the maximum force exerted is recorded. Nov 11, 2025 · Enter the bollard pull force and the efficiency factor into the calculator to determine the towing force. Bollard Pull 23 Febbraio 2022 |By Maurizio Garipoli Precedente Jul 6, 2006 · Bollard pull is just Kt evaluated at J=0 for any n. Please find attached the excel sheet. Aug 24, 2022 · Use this pump horsepower calculator to determine any pump's hydraulic and shaft power. When a company decides on chartering a vessel, a This document discusses methods for estimating the bollard pull of tugboats during preliminary design. 2 to 1. Com seus algoritmos e parâmetros sofisticados, a calculadora determina com precisão a força de tração do cabeçote, permitindo que os profissionais marítimos garantam In a bind you can just calculate kt and kq for a near zero advance coefficient. 21 =3. The theme of this paper is not to criticise or be judgmental, but to question the use of bollard pull fi gures as the arbitrary factor for decision-making on tug selection or design and to The Bollard test measures motor thrust. You simply have to check that your operator has such a method in place and is complimented by a sufficiently rigourous Standard Operating Procedure (including record keeping) that your boss can have confidence that it meets any statutory requirements. It says that the pull is given by: T = 11. Conversion Horsepower to Ton Horsepower (hp) is the name of several units of measurement of power, the rate at which work is done. Feb 22, 2020 · In addition, for scenarios concerning hazardous cargo that require compensating for sideway/lateral ship momentum, users can calculate the tug/pull power output to be applied 30 meters before the The shape of the engine curve is a fundamental part of a proper equilibrium-torque analysis, and it is the only way to calculate the real in-service bollard pull that would be achieved at the time of the bollard pull test. I now know more about tugs and bollard pull than I did before. Towing force is influenced by several factors, including the bollard pull force (the maximum pulling capacity of a tug), and the efficiency pull factor, which accounts for losses due to friction, drag, and other operational inefficiencies. Calculate Engine Horsepower with our Free Online tool. how this conversion from KN or N to tonnes is done? Jan 20, 2010 · Bollard pull testing, which produces a good measure of a tugboat’s pulling power, is becoming standard practice for newly built steel tugs, especially for those that are fully rated by a classification society. Apr 14, 2020 · A smartphone app has been launched providing marine pilots with a tool to calculate the number of tugs and power required in different situational and environmental conditions. The test is to be monitored by ABS surveyors and equipment must be calibrated, with two surveyors required unless a continuous recording device is Aug 17, 2025 · This app uses data collected by the user to calculate the tug's power and bollard pull required to push a barge at a specified speed and environment.