Sector Gate for Clinker and Aggregate Bulk Loading
Single-Blade Curved Gate for Silo and Hopper Discharge Control
What Is a Sector Gate?
A sector gate, also called a curved blade valve in dry bulk loading systems, is a heavy-duty discharge device that uses a single curved blade rotating around a fixed shaft to open, close or regulate the gravity flow of clinker, aggregates and other dry granular materials. LVRUI sector gates are installed below silos, storage bins and hoppers, typically above a clinker bulk loader, aggregate loading chute, belt conveyor or pan conveyor. The opening size, blade structure, drive arrangement, wear protection and control method can be customized according to the material and loading system.
Clinker and Aggregate Loading Applications
The sector gate is designed for gravity discharge points handling coarse, free-flowing and abrasive bulk materials.
| Application | Typical Material | Installation Position | Downstream Equipment |
|---|---|---|---|
| Clinker bulk loading | Cement clinker and clinker granules | Below clinker silo or storage hopper | Clinker bulk loader |
| Aggregate truck loading | Sand, gravel and crushed stone | Below aggregate bin | Aggregate loading chute |
| Limestone discharge | Limestone particles and crushed limestone | Below silo or hopper | Belt or pan conveyor |
| Slag material handling | Granulated slag and selected mineral materials | Below storage bin | Chain or belt conveyor |
| General granular material discharge | Dry coarse particles | Below hopper or surge bin | Loading or conveying equipment |
The sector gate controls material entering the equipment below it. The sector gate controls gravity discharge into the downstream equipment, while horizontal material transfer is handled by the connected conveyor or loading system. For continuous transfer of clinker and other abrasive granular materials after silo discharge, the sector gate can also feed a heavy-duty chain conveyor.
For general process and particulate-emission information related to Portland cement manufacturing and clinker handling, refer to the U.S. EPA’s technical guidance.
How Does a Single-Blade Sector Gate Work?
The curved gate blade is connected to a rotating shaft mounted across the discharge opening. When the actuator moves the shaft, the blade rotates along an arc and changes the effective outlet area.
In the closed position, the curved blade covers the discharge opening and interrupts gravity discharge. Actual shut-off performance depends on the particle size, blade clearance, sealing arrangement and material trapped around the closing edge. As the blade rotates away from the opening, clinker or aggregate falls by gravity into the bulk loader, loading chute or conveyor below.
The sector gate can be configured for full-open and full-closed operation. Adjustable intermediate opening is available when the selected actuator and position-control arrangement support this function. Partial opening can reduce the initial material surge, but the gate should not be treated as a precision weighing or dosing device. Partial opening can reduce the instantaneous material flow and limit sudden impact on downstream equipment.
A sector gate is suitable for coarse flow regulation, but it is not a precision weighing feeder. Applications requiring accurate mass dosing should use a suitable feeder or weighing system together with the gate.
Key Features
✅ Single Curved Gate Blade
The single-blade structure rotates around a fixed shaft and requires less horizontal movement than a conventional linear slide gate.
✅ Suitable for Coarse Granular Materials
The gate is intended for clinker, aggregates, limestone particles, slag granules and other dry bulk materials that may not be suitable for powder-type flow control valves.
✅ Controlled Silo Discharge
The opening area can be changed to control material discharge into a clinker bulk loader, aggregate loading chute or downstream conveyor.
✅ Heavy-Duty Structural Design
The blade, shaft, support frame and housing can be designed according to the outlet size, material load and required operating frequency.
✅ Wear-Resistant Options
Replaceable wear plates, wear-resistant liners and reinforced blade surfaces are available for abrasive clinker and aggregate applications.
✅ Multiple Drive Configurations
Electric, electro-hydraulic and pneumatic drive arrangements can be selected according to the required force, operating speed and site control system.
✅ Local and Remote Control
Limit switches, position feedback, local control boxes and PLC-compatible signals can be included according to the project requirements.
✅ Customized Connection Dimensions
Square or rectangular gate openings can be manufactured to match the silo outlet, with optional transition connections for round upstream or downstream interfaces.
Main Components
A typical sector gate can include:
✅ Inlet connection frame
✅ Gate housing and structural support
✅ Single curved sector blade
✅ Main rotating shaft and external bearings
✅ Electric, electro-hydraulic or pneumatic actuator
✅ Connecting arm and linkage mechanism
✅ Open and closed position limit switches
✅ Optional wear-resistant liners and local control box
The final component arrangement depends on the gate size, actuator type, installation space and material conditions.
Available Drive Options
Electric Sector Gate
An electric geared actuator provides controlled opening and closing with limit switch feedback. Adjustable intermediate opening can be included when the actuator is equipped with a suitable positioning function.
Electro-Hydraulic Sector Gate
An electro-hydraulic push rod provides a compact, self-contained drive arrangement for heavy-duty clinker and aggregate discharge applications. The required thrust, stroke and linkage geometry are selected according to the gate size, material head and operating mode.
Pneumatic Sector Gate
A pneumatic cylinder provides relatively fast full-open and full-closed operation where a stable compressed-air supply is available. Intermediate positioning requires an additional positioning system or mechanical opening control.
The drive method should be selected according to the outlet size, material head, particle accumulation, required opening speed, operating frequency, control method and available power supply.
General Configuration Options
| Item | Reference Configuration |
|---|---|
| Product Type | Single-blade sector gate |
| Main Function | Open, close or regulate gravity discharge |
| Suitable Materials | Cement clinker, sand, gravel, crushed stone, limestone and similar dry granular materials within the confirmed particle-size and temperature range |
| Installation | Below silo, storage bin or hopper |
| Opening Shape | Square or rectangular; customized transition connections available where required |
| Opening Size | Customized according to the silo outlet and capacity |
| Gate Blade | Curved single-blade structure |
| Drive Options | Electric, electro-hydraulic or pneumatic |
| Operating Mode | Full open/close; adjustable opening available with a suitable position-control configuration |
| Main Material | Carbon steel or stainless steel |
| Wear Protection | Optional wear plates and internal liners |
| Position Detection | Open and closed limit switches; optional position feedback |
| Control | Local, remote or PLC interface |
| Installation Direction | Vertical gravity discharge |
| Downstream Equipment | Clinker bulk loader, aggregate loading chute, belt conveyor, pan conveyor or chain conveyor |
These specifications are for preliminary selection only. The final gate size and drive force must be determined according to actual operating data.
Materials and Wear Protection
Standard sector gates are manufactured from carbon steel, with stainless steel available for applications requiring corrosion resistance or material cleanliness.
For abrasive clinker, crushed stone and similar materials, optional wear protection includes:
✅ Replaceable wear plates or internal liners
✅ Reinforced blade and material-contact edges
✅ Thicker blade construction
✅ Replaceable sealing or scraping strips
✅ External or protected shaft bearings
The sector gate is not pressure-tight, gas-tight or completely dust-tight unless specially designed. Any sealing or leakage requirements must be confirmed before manufacture.
Sector Gate vs Jaw Gate vs Slide Gate
| Gate Type | Blade Movement | Typical Material | Main Application |
|---|---|---|---|
| Sector Gate | One curved blade rotates around a fixed shaft | Clinker, aggregates and coarse granular materials | Silo discharge and bulk loading flow control |
| Electro-Hydraulic Jaw Gate | Two opposing blades open and close from both sides | Clinker, aggregates and other granular materials | Heavy-duty discharge with a central opening |
| Slide Gate Valve | Flat blade moves in a straight line | Powder or general dry bulk materials | Isolation and full open-close control |
| Flow Control Gate Valve | Powder flow regulation structure | Cement, fly ash, lime powder and mineral powder | Fine powder discharge and flow adjustment |
Information Required for Sector Gate Selection
Please provide the following information before quotation:
| Required Information | Details |
|---|---|
| Material | Clinker, sand, gravel, limestone, slag or another material |
| Bulk Density | Operating bulk density |
| Particle Size | Minimum, average and maximum particle size |
| Material Temperature | Normal and maximum temperature |
| Required Capacity | Discharge or loading rate in t/h |
| Silo Outlet | Shape and dimensions |
| Material Head | Approximate material height above the gate |
| Downstream Equipment | Bulk loader, loading chute or conveyor |
| Drive Preference | Electric, electro-hydraulic or pneumatic |
| Operating Mode | Open-close or adjustable opening |
| Power Supply | Voltage, frequency or available air pressure |
| Wear Requirement | Standard or reinforced wear protection |
| Control Requirement | Local, remote or PLC interlock |
| Site Information | Layout, installation drawing and available space |
Material head is especially important because the material load acting on the blade affects actuator force and shaft design.
Manufacturing, Inspection and Delivery
LVRUI manufactures the sector gate according to the approved dimensions, drive arrangement and supply scope.
Before shipment, the inspection can include:
✅ Inlet and outlet dimensions
✅ Blade rotation and operating direction
✅ Full-open and full-closed positions
✅ Actuator and linkage movement
✅ Limit switch operation
✅ Shaft, bearing and wear-liner installation
The sector gate is normally supplied as a standalone unit. Site installation, silo connection, electrical wiring and final system integration are completed by the customer or local installation team unless otherwise agreed.
Sector Gate FAQs
What is a sector gate used for?
A sector gate is used below a silo, bin or hopper to open, close or regulate the gravity discharge of clinker, aggregates and other coarse granular materials into bulk loading or conveying equipment.
Can a sector gate regulate clinker discharge flow?
Yes, when the selected actuator and position-control arrangement support intermediate positioning. The curved blade can change the effective outlet area for coarse flow regulation, but the sector gate is not a precision feeder or weighing device.
What is the difference between a sector gate and a jaw gate?
A sector gate uses one curved blade rotating from one side. A jaw gate normally uses two opposing blades that open from both sides and form a central discharge opening.
Can the sector gate be used for sand and aggregate loading?
Yes. It can be installed below aggregate bins to control sand, gravel and crushed stone entering an aggregate loading chute or truck loading system. Wear-resistant protection should be selected according to material abrasiveness.
Is a sector gate suitable for cement powder?
It can handle some dry materials, but it is generally intended for clinker and coarse granular products. Fine cement powder applications normally use a flow control gate valve or slide gate selected specifically for powder handling.
What information is required for a sector gate quotation?
Please provide the material, bulk density, particle size, temperature, capacity, silo outlet dimensions, material head, downstream equipment, drive method, control requirements, power supply and installation drawing.
Need a Sector Gate for Your Loading System?
Send us your material data, silo outlet dimensions, required capacity, particle size, temperature, preferred drive method and site drawing. LVRUI will recommend a suitable single-blade sector gate configuration for your clinker or aggregate bulk loading system.
✅ Sector gates for clinker and aggregate loading
✅ Electric, electro-hydraulic and pneumatic drives
✅ Customized square and rectangular openings with optional transition connections
✅ Optional wear-resistant blade and housing protection
✅ Local, remote and PLC-compatible control options