Cylindrical screw flight with cutouts

The cylindrical screw flight is a challenge to make due to the following facts:

• The cylindrical screw flight has outer diameter Ø1145
• The material is 15 mm. thick
• The material is hardended steel
• The screw flight has cutouts

When cylindrical screw flights are added with cutouts or ribbons they require a special design before the flight blanc can be created. BEMA has many year of experience in designing screw flights with added features such as cutouts.

How do I give BEMA the right information about my cylindrical screw flight with cutouts?

1. Send us a drawing where we can see all the measurements
2. Be sure that you specify the material correct – it can save you costs
3. If the cylindrical screw flight has big cut-outs – more than 10% of the area ask for a prototype flight

If you shall use the screw flight in your workshop, you shall look for screw flights that:

1. Fits to the innertube
2. Is easy to mount
3. Have stable and perpandicular connections to the next screw flight

Point 3. is important. This can save you many working hours in your workshop compared with poor quality flights. The quality of a cylindrical screw flight is a matter of trust. We recommend to start ordering a small amount of cylindrical screw flights first time and check. Secondly to check the time spend for mounting and welding. When ordering larger amount then takes this into considerations when you evaluate the price.

Read about BEMA screw flights here

FAQ on Cylindrical Screw Flights with Cutouts

1. What makes cylindrical screw flights with cutouts difficult to manufacture?

Cylindrical screw flights become significantly more complex when they combine a large outer diameter, thick material, hardened steel, and cutouts. These factors influence how the blank can be formed, how the material behaves under stress, and how accurately the final geometry can be achieved. Cutouts in particular require a specialized design approach before the blank can even be created, ensuring that the flight maintains structural integrity during forming and welding.

2. What information does BEMA need to design and produce these screw flights?

A complete technical drawing with all measurements is essential. The material specification must be correct, as choosing the wrong grade can increase cost or reduce durability. If the screw flight includes large cutouts—typically more than 10% of the total area—it is recommended to request a prototype first. This allows verification of geometry, fit, and forming behavior before committing to a full production batch.

3. What should I consider if I plan to mount the screw flights in my own workshop?

The flights must fit the inner tube precisely, be easy to mount, and have stable, perpendicular connections to the next flight. Poor alignment or unstable joints can lead to many extra working hours during assembly. Ensuring high‑quality flights reduces welding time, improves accuracy, and minimizes rework.

4. How can I evaluate the quality of cylindrical screw flights before ordering larger quantities?

Because quality is a matter of trust, it is recommended to start with a small batch. This allows you to check dimensional accuracy, ease of mounting, and the time required for welding and assembly. When scaling up to larger orders, these practical observations should be factored into your cost evaluation.

5. Why is material specification so important for screw flights with cutouts?

Hardened steel and 15 mm thickness require precise forming methods, and incorrect material selection can lead to deformation, cracking, or excessive wear. Proper specification ensures durability, predictable forming behavior, and long‑term performance in demanding applications.