The Crest Gate is a spillway style gate used for water level control and trash sluicing. It consists of a reinforced leaf with bottom hinges mounted to the waterway floor. The gate is opened and closed by rotating about these hinges. In the lowered position, the gate leaf conforms to the profile of the spillway crest. The gate is typically operated with a hydraulic cylinder mounted on adjacent pier. For longer Crest Gates a cylinder at each end is provided. The cylinders can also be located under the gate or within a vault connected to the hinged torque tube. Low friction self-lubricated bearings are used at all connections. Stainless steel side seal plates are embedded in walls for continuous sealing at all positions. The Crest Gate can be held in any position to maintain upstream water level. Gate position sensors can be programed with operators to modulated or restore gate position. The Crest Gate is an excellent gate for passing ice and floating debris downstream.
Roller gates are vertical lift gates with a series of rollers or wheels located along each side of the leaf. The rollers transfer hydraulic load from the gate to the roller tracks mounted in the guide slots on each side of the gate opening. The wheels minimize frictional forces when raising and lowering the gate reducing the load on the gate operating system. Roller Gates are typically used where opening sizes are too large to efficiently use slide gates or for applications where gravity closure is a requirement. They are usually hydraulically operated to accommodate gravity closure but can also be operated electrically using either an electric actuator or wire rope drum hoist.
The Slide Gate is one of the more basic style of water control gates. Typically used at low to medium heads, this gate consists of a flat reinforced gate leaf with low friction bearing pads and perimeter seals. The Slide Gate operates vertically within a new or existing guide frame. These gates may be operated with a hydraulic cylinder or a screw stem system using manual gearboxes or electric actuators. A common application for Slide Gates is on an intake structure. A Slide Gate may also be used as a Weir Gate that lowers to open. The water passes over the top making this style useful for passing floating debris. Dual stem arrangements can be provided for extra wide gates.
Tainter gates, also referred to as radial gates are primarily used as spillway (flood control) gates due to their simplicity and efficient design. They consist of a curved skinplate reinforced by horizontal or vertical stiffening ribs and supported by radial arms on each side of the gate. The operating machinery is located above the tainter gate and typically includes wire rope hoists, chain or drum hoists to allow for full travel with minimal overhead super structure.
Bulkhead Gates and Stop Log Panels are mainly used to isolate a waterway structure for maintenance. These gates or panels are installed and removed under balance head conditions with a crane. Commonly, a Bulkhead Gate refers to a single panel and Stop Logs are furnished in multiple sections to reduce required lifting forces. A reinforced gate leaf with bearing pads and rubber seals is the basic construction. Both types require lined guide slots in the walls to hold them in place and seal. A lifting beam with engaging hooks is typically used to place and remove stop logs. A Bulkhead gate may use a lifting beam or connect directly to a wire rope hoist. Filling valves may be included in these gates to balance water pressure before removal. Bulkhead gates may be stored in the guides if space allows. Stop logs are usually stored out of the guides wherever ground space is available.
A Draft Tube Gate is a form of bulkhead gate for sealing off a draft tube from downstream pool.
Steel-Fab floating bulkheads consist of a series of sealed caissons with integral ballast chambers that can be filled with water or pressurized with air. The caissons are assembled on the impoundment and then the appropriate ballast chambers are filled with water to vertically orientate the bulkhead and moved into position in front of the corresponding spillway gate. The bulkhead is seated to the dam or piers once a differential head is created. It can also be move to an adjacent spillway bay once a balanced head condition is achieved. To remove the bulkhead the chambers are vacated with air allowing the bulkhead return to a horizontal orientation.
Jet Flow Gates are used as regulating gates to provide controlled discharge on outlet and bypass structures. They are most commonly installed for free discharge in the horizontal direction, but some are set at a downward angle or below tailwater for submerged discharge. The Jet Flow Gate is like a bonneted slide gate in appearance but includes a circular floating seat ring. The seat ring, or seal ring, is a tapered orifice and the primary design feature that contracts flow through the gate body and safely discharges downstream. The contracting flow allows air to be introduced without cavitation or vibration. A sliding gate leaf controls the opening and flow rate. The Jet Flow Gate can be throttled at any position including small openings under high head pressure. The ability to safely regulate flow and trouble-free performance records make the Jet Flow Gate an excellent choice for outlet works.
Steel-Fab has developed the capability to install a Jet Flow Gate within a larger Roller Gate. This arrangement allows controlled minimum flow to be provided without constructing a separate bypass structure.
Steel-Fab Broome Gates, also known as Caterpillar Gates, are roller-mounted vertical lift gates supported along either side by stainless steel roller chains. Otherwise, their construction and function is very similar to that of Roller Gates. Broome gates feature a sloped sealing surface. However, if the sealing surface is vertical, they are sometimes called Coaster or Tractor Gates.
Miter Gates are used to close off the entrance and exits of navigational locks to allow passage between various levels in a river system. Miter gates are typically hydraulically operated and are used to provide sustainable river navigation.