ADAPTER-- A coupling or similar device that permits
fittings with different-sized openings (apertures) to
weld bead while in the molten state. The backing
be joined together.
strap may or may not be removed after welding is
AIR-DRIED LUMBER--Lumbered seasoned by
being permitted to dry naturally.
BARNACLES-- Small shellfish that are found
attached to the bottoms of vessels and to pilings and
AISI--American Iron and Steel Institute. Produces a
other submerged structures.
numerical index for the classification and
BELL--The recessed or enlarged female end of a
pipe into which the male end of the next pipe
ALLOY-- Any composite metal produced by the
mixing of two or more metals.
BEND-- A curved length of pipe bent to a radius larger
than that of an elbow. The term l/8 bend represents
ALLOYING-- A procedure used to add elements,
a 45-degree bend, l/4 represents a 90-degree bend,
other than those that usually make up a metal or
and l/2 represents a 180-degree bend.
alloy, to change the characteristics and properties of
the base metal.
BEND ALLOWANCE--An additional amount of
metal used in a bend in metal fabrication.
ALLOYING ELEMENTS--Elements added to
nonferrous and ferrous metals and alloys to change
BENDING ROLLS--A large machine used to give
their characteristics and properties.
curvature to plates by passing them through and in
ANGLE VALVE--A stop valve is actually a
contact with the three rolls.
combination valve and elbow, since its outlet
BENDING SLAB--Heavy cast-iron blocks with
branch is at right angles to its inlet branch.
square or round holes used for "dogging down."
The blocks are arranged to form a large solid floor
on which frames and structural members are bent
ASTM--American Society for Testing Materials.
BEVEL-- A term for a plane having any angle other
AWR--Automated Work Request. A computer-
than 90 degrees to a given reference plane. Also, a
produced 3-M form that displays the information
small tool similar to a try square except that the
found on the 4790/2K and the planning information
blade is adjustable for taking bevels.
found on the 4790/2P and that is used by the IMA
for advanced planning and work completed.
BILL OF MATERIAL--A list of standard parts or
materials needed to fabricate an item.
BACK-GOUGE-- A term used in welding for the
removal of the root and first layer of weld
BISECT--To divide into two equal parts.
beads before welding the opposite side of a
BLANK FLANGE--A flange that is complete except
BACK-PRESSURE VALVE--A valve that is similar
BOLT-- A metal rod used as a fastening. With a few
in design to a low-pressure valve, but which is
exceptions, such as drift bolts, a head or shoulder is
capable of opening independently of the pressure,
made on one end and a screw thread to carry a nut
is cut on the other.
BACKING STRAP--A term used in welding where
BOLTING UP--Securing, by means of bolts and nuts,
the root of the weld joint is closed by the application
parts of a structure in proper position for permanent
of a backer plate. This backer plate is used as a base
for depositing weld metal and preventing the
attachment by riveting or welding.