RIVETING

Exercise 1

Read this text, translate it into Estonian and learn the words in bold

Riveting is a simple but effective way of joining metals. It is used extensively in shipbuilding, aircraft construction, civil engineering, etc. Riveting is often used when a simple movable joint is needed; a pair of tongs is an example.

Rivets may be made of mild steel, copper, brass, aluminium or stainless steel and are available with a variety of heads. Usually, the metal the rivet is made of, should match the materials being joined. When buying, it is necessary to state the type of head, length, diameter of shank and material. Rivets are sold by weight. The length of the rivet shank is calculated by adding one and a half times the rivet diameter to the metal thickness. The diameter of the rivet shank is calculated by the formula 1,5 t where t is the metal thickness.

The rivet centers are spaced one and a half times the shank diameter from the edge of the metal and three times the shank diameter between rivets.

Careful alignment of the holes in each plate is important. Whenever possible, all the holes are drilled in one plate first. One matching hole is then drilled in the second plate and a rivet is inserted and closed. Using the holes in the top plate as a guide, drilling of the other holes in the second plate is completed.

Snap-head rivets are widely used as they are strong and easy to close. Conical-head rivets are very decorative and are easily closed. The flat-head rivet with its wide head gives support over a good area and is therefore particularly suitable for thin sheet metal. The countersunk head is used when an unbroken surface is needed.

The conical-headed rivet is finished off with the pain of the hammer. The snap-headed is roughed into shape with the hammer and finished with the snap. The flat-headed rivet is roughed into shape with the pain and finished with the flat.

Before welding techniques and bolted joints were developed, mental framed buildings and structures such as the Eiffel Tower, Shukhov Tower and the Sydney Harbour Bridge were generally held together by riveting. Also automobile chassis were riveted. Riveting is still widely used in applications where light weight and high strength are critical, such as in an aircraft. Many sheet-metal alloys are preferably not welded as deformation and modification of material properties can occur.

Exercise 2

Watch the video about riveting and pay attention to the explanation