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What Is a Bonnell Spring System and How Is It Made?
The Bonnell spring system remains one of the most widely used support structures in mattresses and sofas—even in 2025. Despite the rise of pocket springs, foam hybrids, and advanced ergonomic materials, countless factories around the world continue choosing Bonnell springs for one simple reason:
✔ Low production cost
✔ High durability
✔ Stable performance
✔ Suitable for mass production
This article explains what a Bonnell spring system is, why it is still popular, and how it is manufactured using modern bonnell spring machine, including both semi-automatic and fully automatic production lines.
What Is a Bonnell Spring System?
In the mattress manufacturing industry, the term Bonnell Spring System is also known as a:
Bonnell Spring Structure
Bonnell Spring Unit
Bonnell Spring Core
It is a support system made by assembling multiple hourglass-shaped steel springs into a complete spring unit. The springs are connected using spiral/helical wires, and the outer frame is reinforced by border rods, forming a stable and durable structure.
By using steel wires of different diameters, manufacturers can produce Bonnell spring units in various firmness levels—from softer to firmer—simply by adjusting the coil diameter, wire gauge, and number of turns.
Typical Bonnell springs contain 4–7 turns, depending on the mattress height and supporting requirements.
Why Bonnell Spring Systems Are Still Popular Today
Even with the rapid growth of new mattress technologies, Bonnell units remain essential in many factories because:
✔ Cost-Effective
Wire consumption is low, and production machinery is relatively affordable.
✔ Highly Durable
The hourglass structure distributes pressure evenly and can withstand years of use.
✔ Efficient for Mass Production
The system is perfect for factories producing high volumes for hotels, dormitories, emerging markets, and sofa manufacturers.
✔ Strong Support
The interconnected design gives a firmer, more stable feel—ideal for customers who prefer a harder mattress.
For these reasons, Bonnell systems are still widely used in mattress factories, sofa manufacturers, and bulk OEM production lines.
How Is a Bonnell Spring System Made?
Bonnell units can be manufactured through two main production methods:
① Semi-automatic production
② Fully automatic integrated production
Below is the complete explanation.
1. Semi-Automatic Bonnell Spring Manufacturing Process
This method uses two separate machines:
(1) Bonnell Spring Coiling Machine
This machine forms the individual hourglass springs.
It performs:
- Wire feeding
- Coiling into double-cone (hourglass) shape
- Knotting
- Cutting
- Heat treatment (tempering)
(2) Bonnell Spring Assembly Machine
In the next step, workers bring the coils to the assembly machine.
The machine then:
- Aligns the springs
- Uses helical/spiral wires to connect them in rows
- Connects rows into a full spring unit
- Adds border rods
- Forms the final Bonnell spring system
Once formed, the Bonnell springs move forward along the output chute instead of falling down. Workers then collect them and feed them into the assembly machine. Check the video below to see how it works step-by-step.
This semi-automatic setup is ideal for small to medium factories:
- Lower investment
- Flexible production
- Easy operation
- Good speed for stable daily output
2. Fully Automatic Bonnell Spring Coiling & Assembly Machine
For factories focusing on high efficiency, low labor cost, and consistent quality, a fully automatic line is the best solution.
This advanced machine integrates all functions into one continuous workflow:
Key Features of the Fully Automatic System
- Automatic wire coiling
- Automatic knotting
- Automatic heat treatment
- Automatic spring alignment
- Automatic row formation
- Automatic spiral wire assembly
- Automatic border rod installation
- Automatic unit shaping
The operator only needs to:
- Input spring specifications
- Spring turns (4–7 turns)
- Spring height
- Number of springs per row
- Number of rows
- Load steel wire onto the wire rack
Then the machine runs automatically.
Benefits
- High precision and stable quality
- One machine replaces multiple workers
- Perfect for large mattress and sofa factories
- Ideal for continuous 24/7 mass production
This type of automatic line is especially suitable for producing double-cone Bonnell spring units used in both mattresses and sofas.
Bonnell Spring System vs. Pocket Spring System
Many people confuse the two systems, so here is a clear comparison.
1. Structural Difference
Pocket Spring System
- Each spring is wrapped in individual non-woven fabric pockets
- Springs do not touch each other
- Connected using glue bonding
Bonnell Spring System
- Springs are connected using spiral metal wires
- All springs are linked together
- No fabric pockets
2. Comfort Difference
Pocket Springs:
Press one corner → only the springs under your hand compress.
Other springs remain independent.
→ Higher comfort, less motion transfer.
Bonnell Springs:
Press one corner → springs across a large area move together.
→ Firmer feel, stronger motion transfer.
3. Which One Should You Choose?
- If you prioritize comfort → choose pocket spring
- If you want cost-effective, durable, and firm support → choose Bonnell spring
For readers interested in how pocket spring systems are made, you can visit our Pocket Spring Machines page.
The Bottom Line
The Bonnell spring system is one of the most reliable and cost-effective spring structures in the mattress and sofa industry. Its combination of durability, firmness, and production efficiency ensures that it will continue playing an important role—especially in large-scale manufacturing.
Whether produced through semi-automatic or fully automatic equipment, modern technology has made Bonnell spring production faster, more precise, and more stable than ever.
