Glossary

Glossary
AWS
American Welding Society. Standards of practice for welding and structural steel connections. AWS D1.1 is the structural steel welding standard. AWS D1.6 is the Stainless Steel welding standard. AWS D1.5 is the Standard for welding bridge connections.
Bulkhead:
A Flat boxlike structure used to shut off water flow in a dam upstream from other gates or equipment, enabling repair or maintenance work.
Bullnose Seal
A flat type of seal designed with a rounded or radial nose or contact area. Sealing under compression, the rounded nose allows the rubber to spread out on each side with less force of compression.
Center Bulb Application
Most often used now as a top seal for a wheel type gate to control bulb movement (rollover) by fastening of the seal flanges on both sides of the bulb. Originally called a caisson seal, used also as a compression seal for sides and bottoms of heavy gates and doors.
Compression
Seal contact by force with seal plate causing change in seal shape at contact area.
Cover
The flap portion of a flap gate.
Deflection
Bending of the stem part of the seal under pressure from water or by interference.
Double Bulb Application
A double bulb type of seal used for gates where water flows both ways such as the mouth of a river or a tidal installation.
Emergency Lock Bulkhead
A large boxlike structure used to close off an area around a lock miter gate, so water can be pumped out leaving an area dry for repair work on the miter gate.
Flush Bottom
The bottom or invert section of the frame that is embedded in the floor slab to provide unrestricted flow.
Frame
The part of the gate that is fixed to the structure and engages the slide
Head
Water level or depth above centerline of gates opening
Head Pressure
The pressure exerted by the weight of water per unit at any given depth below the surface (approx…4 lb. per square inch per foot of depth.).
Hydro Plant
A plant built in conjunction with a dam to provide water flow through turbine generators creating electricity.
Intake Gate
A gate provided to shut off flow of water into a water intake passage or penstock leading to a turbine.
J-Seal
A neoprene (rubber) seal used to control leakage on slide, roller, and radial gates. Generally has a cross-sectional shape of the letter “P.”
Lift
The device that produces torque and/or thrust to operate the gate.
Miter Lock Gate
One gate consists of two leaves hinged at the outer ends, closing with an angular or miter contact at the center. These gates are sealed at the bottom and may also have partial rubber sealing at both the miter and hinge or pintle ends.
Pedestal
A support for the lift generally having flanges and a hollow or tubular mid-section.
Pump Station
A plant built with diesel or electric powered pumps to move water for drainage or storage. Also, such stations are built to move sewage to a treatment plant.
Radial Gate
A Gate with a curved skin or face plate connected with steel arms to a trunnion or axle. It is usually lifted or lowered by a cable connected to a hook at the top of the gate rotating on the trunnion shaft as it is moved. This type of gate is used at an opening in the top of a darn to control the water reservoir level since it can be opened partially to control the amount of flow.
Rising Stem
A lift/stem arrangement where the stem rises above the lift as the gate opens upward.
Roller Gate
A Gate used in a levee opening for flood control, usually being so wide or long that rollers are required at the bottom to support it during opening and closing.
Seat
The frame of a flap gate. It is usually mounted to a pipe flange or wall thimble.
Seating Face
Corrosion-resistant metal strips, machined and mounted in a dovetail groove on the slide and frame of a sluice gate.
Self-contained
A gate with an extended frame to support a yoke and lift mounted to the yoke.
Slide
The sliding or moving part of the gate.
Slide Gate
A 3 or 4-sided water control gate fabricated from structural steel or aluminum shapes.
Sluice Gate
A 4-sided water control gate fabricated of cast iron. Usually a smaller rectangular type of gate used to control water level or flow, but may also be a small radial type of gate.
Spillway
An opening in a dam for water overflow; usually closed off with some type of gate (radial or vertical lift) but may be uncontrolled; just an open area for high water to overflow.
Stem
A threaded rod that allows operation of the gate as a power screw.
Stem Block
A block that transmits the thrust of the stem to the slide and prevents rotation of the stem to provide linear movement of the slide.
Stem Guide
The devices used to provide lateral support of the stem to prevent buckling.
Stoplog
Similar to a bulkhead but smaller and stacked in sections on top of each other; usually removable one at a time.
Swing Gate
A small to medium size gate used in a levee opening that is equipped to swing on hinges from one end to open or close for flood control.
Tainter Gate
Another name for a Radial Gate.
Tainter Valve
A radial type gate used in a submerged location such as in a navigation lock where it is used to open or close water passages which flood or drain the lock.
Trash Rack
A metal grid structure placed upstream of a gate such as an intake gate to catch trash and debris, preventing it from entering a water passage where it could damage equipment such as a turbine.
HMW
Ultra High Molecular Weight polyethylene used as a guide and wear surface material for slide gates.
Wall Thimble
A cast iron wall piece embedded in concrete to provide a machined mounting surface for cast iron gates.
Wedge Block
Device that engages the wedge block and squeezes the seating faces together to limit leakage and is mounted on the slide of a sluice gate.
Wheel Gate
A rectangular vertical lift gate designed with a number of wheels fixed on axles on each side with move up and down slots built in on either side of the gate opening. This type of gate is usually provided for water closure under high heads such as a service or emergency gate.
Yoke
The horizontal members that support the lift of a self-contained gate.