Air Pressure Solids Level Switch for Cement Loading Spout
Air-blow type full-level detection switch for cement tanker loading, fly ash loading and dry ash bulk loading systems
What Is an Air Pressure Solids Level Switch?
An air pressure solids level switch is a full-level detection device used on cement loading spouts, dry ash bulk loaders and powder tanker loading systems. It is designed for dry powder and bulk solids such as cement, fly ash, mineral powder, lime powder and dry ash, not for liquid level detection.
The device has a built-in air pump. During bulk loading, the pump sends air through a 10–12 mm tube to the lower blowing port of the loading head. When the loading head extends into the cement tanker and the powder blocks the blowing port, the air pressure changes. This pressure change is converted into an electrical switch signal and sent to the control cabinet.
After receiving the full-level signal, the control system immediately closes the feeding valve and stops unloading. This helps prevent tanker overfilling, dust leakage and material spillage during cement or dry ash loading.
Working Principle
- The cement loading spout is lowered into the tanker inlet.
- The air pressure solids level switch starts working together with the bulk loader.
- The built-in air pump sends air through the tube to the blowing port at the lower center of the loading head.
- During normal loading, the air outlet remains open and air flows into the tanker.
- When cement, fly ash or dry powder reaches the full level and blocks the blowing port, the back pressure changes.
- The air-electric converter sends a full-level switch signal to the control cabinet.
- The control cabinet immediately closes the valve and stops unloading to prevent overfilling.
Main Specifications
| Item | Specification |
|---|---|
| Product name | Air Pressure Solids Level Switch |
| Application | Cement loading spout, dry ash bulk loader, tanker loading system |
| Detection method | Air-blow pressure detection |
| Power supply | 220V |
| Output signal | Switch signal |
| Enclosure material | Powder-coated carbon steel |
| Installation position | On the lifting platform of the bulk loader |
| Air tube size | 10–12 mm |
| Air tube connection | Connected to the air inlet of the loading head |
| Blowing port position | Lower center of the loading head, extending into the tanker |
| Stop response | Immediate stop after full-level signal |
| Suitable materials | Cement, fly ash, mineral powder, lime powder, dry ash |
| Main function | Full-level detection, valve shut-off, overfill protection |
Why Use an Air Pressure Solids Level Switch?
✅ Designed for dry powder and bulk solids, not liquid level detection
✅ Built-in air pump for air-blow full-level detection
✅ No rotating paddle inside cement powder
✅ Immediate stop signal when the tanker is full
✅ Helps prevent cement tanker overfilling
✅ Reduces dust leakage and material spillage during loading
✅ Suitable for cement, fly ash, mineral powder, lime powder and dry ash
✅ Easy to install on existing cement loading spouts and dry ash bulk loaders
✅ Can interlock with flow control gate, slide gate valve and control cabinet
Applications
The air pressure solids level switch is mainly used for full-level detection in dry powder tanker loading systems.
Typical applications include:
✅ Cement tanker loading
✅ Fly ash bulk loading
✅ Dry ash bulk loader systems
✅ Lime powder loading systems
✅ Mineral powder loading systems
✅ Cement silo discharge and truck loading stations
✅ Powder loading spouts with automatic stop control
✅ Bulk loading systems requiring overfill protection
Difference from Rotary Paddle Level Switch
| Item | Air Pressure Solids Level Switch | Rotary Paddle Level Switch |
|---|---|---|
| Detection method | Air pressure change | Paddle rotation resistance |
| Contact with material | Only the blowing port contacts powder | Paddle works inside powder |
| Main application | Cement tanker full-level detection | Silo or hopper point level detection |
| Moving parts in powder | No rotating paddle in material flow | Rotating blade contacts material |
| Response during loading | Immediate full-level stop signal | Depends on paddle contact condition |
| Best use case | Cement loading spout and dry ash bulk loader | Fixed silo or bin level detection |
Why It Is Suitable for Cement Tanker Loading
Cement tanker loading is a dusty and fast loading process. If the full-level signal is delayed or unreliable, cement powder may overflow from the tanker inlet, causing dust pollution, material loss and cleaning problems.
Cement tanker loading is a dusty and fast loading process. If the full-level signal is delayed or unreliable, cement powder may overflow from the tanker inlet, causing dust pollution, material loss and cleaning problems.
The air pressure solids level switch is designed for this working condition. The blowing port is placed at the lower center of the loading head and extends into the tanker. Once the powder reaches the set full position and blocks the port, the switch sends a full-level signal immediately.
This makes it especially suitable for cement loading spouts where automatic stop control is required.
For general application reference, point level detection is widely used in truck loading systems to prevent overfilling and improve loading efficiency, especially in dusty cement loading conditions.
System Interlock
The air pressure solids level switch can be connected with the control cabinet of the bulk loader. When the full-level signal is triggered, the control cabinet can stop the loading process by controlling related equipment.
Common interlock equipment includes:
✅ Flow control gate
✅ Slide gate valve
✅ Rotary valve
This helps the whole loading system work in a safer and cleaner way.
Materials Handled
This product is suitable for dry powder and fine bulk solids, including:
✅ Cement
✅ Fly ash
✅ Dry ash
✅ Mineral powder
✅ Lime powder
✅ Dry powder materials with similar flow characteristics
It is not designed for water, slurry, oil or liquid level detection.
Installation Notes
The device box is usually installed on the lifting platform of the bulk loader. A 10–12 mm air tube connects the device to the air inlet of the loading head.
The blowing port should be arranged at the lower center of the loading head and extend into the tanker during loading. This position allows the switch to detect the full-level condition when the powder reaches the loading head outlet area.
Before installation, the air tube route, loading head structure and control cabinet signal connection should be confirmed according to the actual bulk loader layout.
Common Problems It Helps Solve
✅ Cement powder overflows from the tanker inlet
✅ Operator cannot judge the full level in time
✅ Loading valve closes too late
✅ Dust leakage occurs at the end of loading
✅ Rotary paddle level switch is easily affected by powder build-up
✅ Existing bulk loader needs automatic full-level stop control
✅ Loading spout needs a simple overfill protection device
FAQs About air pressure solids level switch
Is this air pressure solids level switch used for liquid level detection?
No. It is not a liquid level switch. It is designed for dry powder and bulk solids such as cement, fly ash, dry ash, mineral powder and lime powder.
How does the air pressure solids level switch detect full level?
It uses a built-in air pump to send air to the blowing port on the loading head. When dry powder blocks the blowing port, the pressure changes. The device converts this pressure change into a switch signal and sends it to the control cabinet.
Where is the device installed?
The device box is installed on the lifting platform of the bulk loader. It is connected to the loading head through a 10–12 mm air tube.
Where is the blowing port located?
The blowing port is located at the lower center of the loading head. During loading, the loading head extends into the cement tanker, allowing the switch to detect the full-level condition inside the tanker.
What happens after the tanker is full?
When the full-level signal is triggered, the switch sends a signal to the control cabinet. The system immediately closes the valve and stops unloading.
Can it be used for fly ash loading?
Yes. It can be used for fly ash, cement, dry ash, mineral powder, lime powder and similar dry powder materials.
Can it replace a rotary paddle level switch?
It depends on the application. For cement tanker loading and dry ash bulk loader full-level detection, the air pressure solids level switch is often more suitable because it does not use a rotating paddle inside the powder flow.
Can it work with a flow control gate or slide gate valve?
Yes. The switch signal can be connected to the control cabinet, which can interlock with a flow control gate, slide gate valve or other feeding valve to stop unloading automatically.
Need a reliable air pressure solids level switch for cement tanker loading?
Partner with LVRUI for professional bulk material handling solutions and responsive technical support.
✅ Get expert quotation and customized solution within 12 hours.
✅ Factory direct supply with strict quality control
✅ Professional engineering support from experienced team
✅ Stable delivery for overseas industrial projects