Dear Readers,
Typical
examples of the bolt for special purposes are as follows:
Stove Bolt
A stove bolt has a round flat head which is beveled on the underside to fit a countersunk hole, it is provided with a slot on the head, as shown in the figure.
For
screwing the bolt into a nut by means of a screwdriver. This is used for
assemblies where precision is of no great importance, and it is desirable to
have the head of the bolt flush with the surface of the work.
Carriage Bolt
Domed, enlarged head shape and Designed to
keep bolt from pulling through suitable tool.
This is used for fastening wooden parts together or for fastening metal parts to wood it has squared portion directly under the head to prevent rotating when the nut is tightened or slackened. A carriage bolt is shown in the figure.
Hook Bolt
The hook bolt, shown Fig. is used in semi-permanent fastening in concrete.
This
is also used in cases where there is no room for a bolt hole through one of the
pieces to be connected, or in cases where a bolt hole would seriously weaken a
piece. So the hook bolt is used for attaching shaft hangers to the flanges of
joists and girders.
Expansion Bolt
This
type of bolt is used in attaching parts to brick, stone or concrete walls and
floors hee bolt has an internally threaded split sleeve which is slipped into a
hole made in the wall and then expanded by running in the screw. This is shown
in Fig.
Foundation or Rag
Bolt
The rag bolt, shown in Fig. is used for fixing into the stone concrete foundation, the head is wider at the bottom than at the top, and is led into a tapered hole.
The
tapered head is cut in an uneven manner (jagged) and moulted lead or sulfur is
poured into the taper hole to fill the space between the lead and the stone or
the concrete as the case may be. Where great strength is required, four
parallel bars or keys are used in addition.
Eye-Bolt
The eye-bolt, shown in Fig. is very commonly used for lifting purpose. It is screwed or turned inside a threaded hole on the top of the machine.
Electric
motors and medium and lightweight machinery are equipped with one or more
eye-bolt so that they may be readily lifted and moved by an overhead crane.
