Live screw bottom with silo

The live screw bottom with silo has been delivered as a complete machine system for conversion of a boiler system from coal to wood chips. It is well known that wood chips can be problematic to handle when they are stored in a silo. The silo above the screw bottom bin is app. 100 m3.

What is the idea to use a live screw bottom for this application?

1. The screw bottom bin feeds directly 4 inlets to the boiler. It is important that the feeding rate is consistent and continous. Each inlet is served by 3 screw rotors.
2. The live screw bottom takes out material from the silo in its hole area. This eliminates the risk of bridge building which is commonly seen when handling wood chips.
3. The bottom is flooded with bulk material, which means that the screw rotors act like dosing screw rotors and ensures the continuos flow rate. The silo is fed by a chain conveyor delivering the wood chips in the top of the silo

Which tasks have BEMA solved in this project?

• The engineers of BEMA has designed the complete system including capacity calculations of the screw bottom
• Designed the screw rotor with the necessary progressive pitch
• Calculated the size of the gear boxes
• Made the complete set of production drawings
• Manufactured the live screw bottom and silo parts in the workshop
• Delivered the solution on-site at the customer site
• Delivered a full documentation description with the product

Designing and manufacturing of a live screw bottom requires a comprehensive engineering task before it is ready to be manufactured. BEMA has the engineers to undertake such tasks, and we can assist in the earlier stage of the project. Over the years BEMA has manufactured different types of live screw bottoms. See examples on these: Live screw bottom for potatoes Live screw bottom for ice flakes

FAQ: Live Screw Bottom with Silo

1. What is a live screw bottom with silo used for?

A live screw bottom with silo is designed to ensure continuous and reliable material flow from large storage silos. In this case, it supports the conversion of a boiler system from coal to wood chips by securing stable feeding to four boiler inlets.

2. Why is a live screw bottom ideal for handling wood chips?

Wood chips often create bridging inside silos, which disrupts material flow. The live screw bottom removes material across its entire area, preventing bridge formation. Because the bottom is fully flooded with bulk material, the screw rotors act as dosing units that maintain a consistent feed rate.

3. How does the system ensure continuous and controlled feeding?

Each of the four boiler inlets is served by three screw rotors. This multi‑rotor setup ensures even distribution and stable dosing. The progressive pitch of the screw rotors and correctly sized gearboxes further support smooth, uninterrupted operation.

4. What engineering tasks did BEMA handle in this project?

BEMA designed the complete system, performed capacity calculations, engineered the progressive‑pitch screw rotors, selected gearboxes, produced all manufacturing drawings, fabricated the live screw bottom and silo components, delivered the system on‑site, and supplied full documentation.

5. Can BEMA support similar projects or early‑stage engineering?

Yes. Designing a live screw bottom requires extensive engineering expertise, and BEMA can assist from the earliest project stages. The company has delivered many variations of live screw bottoms for different materials and applications.