Stevpris Mk5 UHC chart

Stevpris Mk5 size in t

Stevmanta VLA UPC chart

Stevmanta Fluke Area (m2)

Typical Ultimate Pull-out Capacity (UPC)

The prediction lines on the “UPC chart” can be expressed in the equations as stated below:

α= Stevmanta fluke / shank angle [deg]

The UPC graph incorporates a Nc- value of 10, α-value of 50 degrees and k-value of 2. The graph clearly illustrates the influence of the diameter of the mooring line or installation line, and whether six strand or spiral strand is used. The typical installation load to obtain a specified UPC is presented on the right vertical axis of the graph.

Introduction

The forces acting upon a ship determine her movement. Some of these forces are controllable and some are not. Some of them can we measure and some we can not.

The ship is subjected to the forces from the wind, waves and current and in shallow water and narrow waterways by the interaction from the bottom, banks or sides of the channel.

Close approach to other vessels generates intership action, and wash from propellers/thrusters from another vessel will also affect our ship.

Some of these forces will vary in size depending on the speed of our, or the other ship, whereas other forces are affecting us all the time.

Forces from pulling an anchor-wire-towing-cable etc, is also an important factor.

This chapter will explain some basis knowledge to Ship handling and Manoeuvring theory but the most important factor in Ship handling is experience.

It is therefore essential that navigators do practice handling of their ship when there are a chance to do so.

Propulsion system

Most vessels do have diesel engines, which through a gear rotate the aft propeller, and an electrical power system generation power to the thrusters.

But some special vessels can have a system with electrical propellers/thrusters, and maybe only having azimuth thrusters whiteout any rudders.

Depending on the layout of your propellers/thrusters/rudders the ship handling can be quite different from one ship type to another.

A continued research and development is taking place within the maritime technology and new engines, propeller and rudder types are invented every year. This chapter will therefore concentrate on some basis knowledge regarding propellers and rudders.