Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering
Transport Technology / Logistic Engineering

G.P.M. Hof Ontwerp van een legbord voor semi-automatische twistlocks
Design assignment, Report 2001.TT.5539, Transport Technology, Logistic Engineering.

At a conventional containership about 35% of the total amount of containers is located at the deck. During the transport these deck-containers are fastened to each other with semi-automatic twistlocks (SATL's). While loading and unloading a containership these twistlocks are manually attached and removed. Some difficulties are encountered in the manually treatment: the current handling of SATL's is arduous, unsafe and it disturbs the loading and unloading process of the crane.

In 1999 O. Tekeli has proposed a concept of using a mobile twistlockstation in which the SATL's are attached mechanical to the containers by the use of a manipulator. By this concept the twistlocks are stored organized at trays.

A tray is suitable for the storage of thirty semi-automatic twistlocks of the type C5AM-DF from All Set Marine Lashings and the type CV-20/DUAL from MacGregor Conver. The tray, dimensioned 1600 mm x 1000 mm x 250 mm, is made of the plastic HDPE (high density Polyetheen) and has a weight of about 65 kg if the tray is made of massive HDPE. When fibre reinforced plastic is used, the weight of the tray will be between 26 en 32 kg.

Each containership with a capacity of 8000 TEU requires 250 trays. The complete Delta containertertninal requires from 1250 to 1500 trays. The trays are stored in frames with a capacity of about 125 trays.

An alternative for the supply of SATL's is the usage of a conveyor instead of trays. This concept offers some major advantages towards the use of trays. A major problem however is the mechanical positioning of the SATL's at the conveyor.

Reports on Logistic Engineering (in Dutch)
Modified: 2001.12.01; , TU Delft / 3mE / TT / LT.