Offshore Tube shear. Pre-design of scale model.
Report 87.3.OS.2281, Transport Engineering and Logistics.
This paper deals with the design of a pair of shears for the cutting of
steel tubes in an offshore environment.
A preliminary investigation [report 87.3.OS.2338], which
is summarized in chapter 3, carried out with a pair of onshore scrap shears,
showed that these shears were basically not suitable for the cutting of tubes.
Quite large changes are required to adapt it to the cutting of tubes. The
quantitative influence of the changes on the required cutting force cannot be
predicted with certainty.
It is recommended to build a scale model of the tube shear, which is specially
designed for the cutting of tubes. The quantification of the cutting forces,
for a shear specially designed to cut tubes, is achieved by means of model
experiments. This paper contains the preliminary design of the model shear,
- the recommendations and conclusions of the preliminary investigation;
- the requirements of HES related to a shear for offshore use.
A preliminary design of a shear is presented for the cutting of two
concentrical tubes, 330 m and 304 mm diameter, which are on a scale of 1:5
to the tubes to be cut offshore.
- the model shear should be used to experimentally determine the influence
on the required cutting force of:
The recommended test situation is shown in a drawing in the report.
- the cutting speed;
- the axial load on a tube to be cut;
- two concentrical tubes, to be cut together;
- the size of the tube.
- handling of the offshore structure components during the cutting activities
should be studied.
- a study should be carried out on how to position the shear on the tubes to
Reports on Transport Engineering and Logistics (in Dutch)
, TU Delft