BUTT-- The end or edge of a plate or timber that comes
BONNET-- A cover used to guide and enclose the tail
squarely against another piece, or the joint thus
end of a valve spindle.
formed. The long edge of a plate is called the edge
BORDER LINES--Dark lines defining the inside
and the short edge is called the end.
edge of the margin on a drawing.
BUTT WELD--A welding along a seam that is not
BOSS-- A socket, with a heavy wall, that is welded or
scarfed or beveled, but is joined by the edges
brazed onto pipe to provide connections for gauges
coming together.
and related fittings.
BYPASS-- A small passage that will permit the passage
BRACKET-- A steel plate, commonly of triangular
of fluid in a system around a larger valve. In this
shape, with a reinforcing flange on its free edges.
way, pressure can be equalized on both sides of the
It is used to connect two parts, such as a deck beam
larger valve so that it may be readily opened or
to a frame, or a frame to a margin plate. It is also
closed as required.
used to stiffen or tie items, such as beam angles to
bulkheads and frames to longitudinals.
BYPASS VALVE--A small pilot valve used in
connection with a larger valve to equalize pressure
BRANCH--The outlet or inlet of a fitting not in line
on both sides of the disk of the larger valve before
with the axis of the system, but making an angle
with it.
the latter is opened.
CALKING-- The operation of jamming material into
BRASS--An alloy composed chiefly of copper and
zinc.
the contact area to make a joint watertight or
oiltight.
causes it to break or snap suddenly with little or no
CALKING TOOL--A blunt-ended chisel used in
prior sign of deformation.
calking.
BRONZE--An alloy composed chiefly of copper and
CAP--A fitting placed over a pipe to make a dead end.
tin.
CENTERLINES-- (l) Lines that indicate the center of
BUCKLE--(l) A distortion, such as a bulge. (2) To
a circle, arc, or any symmetrical object; consisting
become distorted. (3) To be bent out of its own
of alternate long and short dashes evenly spaced.
plane.
(2) The middle line of the ship from stem to stem
as shown in any waterline view. (3) Well-defined
BULKHEAD FLANGE--A flange with two bolt
knife or gauge lines placed upon the work to serve
circles; the larger circle is to secure the flange to the
bulkhead, the smaller is to secure the pipe to the
as a point from which dimensions will be measured.
flange. This type of flange is used where piping
CHAMFER--A bevel surface formed by cutting away
must pass through a watertight bulkhead.
the angle of two intersecting faces of a piece of
BULKHEAD SLEEVE--A sleeve welded into a
material.
bulkhead with piping butted together and welded
CHECK VALVE--An automatic nonreturn valve, or a
onto each end of the sleeve. If a section of pipe can
valve that permits a fluid to flow in one direction
be slipped through the sleeve, there is no need of
but automatically closes if the fluid begins to flow
butted ends inside the sleeve. However, the pipe
in the opposite direction.
must be welded to the sleeve at each end to make a
watertight joint at the bulkhead.
CLAMP-- A metal fitting used to grip and hold wire
ropes. Two or more may be used to connect two
BURR-- The rough, uneven edge of a sheared or
ropes in lieu of a short splice or turning in an eye.
burned plate, or the area around a punched or
Also, a device generally operated by hand to hold
burned hole. Also, a washer-shaped piece of metal
two or more pieces of material together, usually
through which the rivet is inserted and against
called a "C" clamp.
which the rivet point is riveted over.
CLEAN-OUT FITTING--One that is equipped with
BUSHING--A hollow plug with internal and external
a cover and handhole to provide access for
threads, used to connect a pipe with a fitting of a
cleaning the pipes.
different diameter.
AII-2