Shapes: Cylinders

A cylinder shape is a thick-walled hollow pipe defined by its

• Inner and outer diameter
• Length
• Azimuth and declination of the axis

The azimuth and declination define the direction of the cylinder axis relative to the connection axes.

The remaining cylinder data are common to all geometric shapes and are described under the shape data and drawing topics.

Cylinders are drawn with circles representing the end faces and a number of rectangular facets around the curved surfaces. The number of facets used is the number of lines specified. Two gives a very simple wire frame profile of the cylinder, whilst a very large number gives a pseudo-opaque cylinder at the expense of drawing speed.

If the cylinder is of the elastic solid type then, on contact with another object, reaction forces are applied

• radially inwards if the object contacts the inner curved surface
• radially outwards if the object contacts the outer curved surface
• axially outwards if the object contacts one of the end faces