Screw flights with outer cuttings

Screw flights with outer cuttings manufactured for a customer far away from BEMA.

• Special made screw flights in Hardox 450 and stainless steel 1.4301/AISI-304

The Hardox-450 screw flight segments are manufactured with cut offs on the outer diameter. This require a special design of the flight blanc. Learn more about BEMA screw flights here

How BEMA deliver screw flights on a long distance 

These screw flights were sent on a long journey to the customer. The customer who ordered these screw flights in Hardox is located  8,975 km from BEMA. BEMA can supply screw flights in a global market. BEMA A/S is not afraid to undertake such tasks. We have established good cooperations with trusted transport companies – and therefore able to ship all our products globally.

Technical Manufacturing Details for Screw Flights With Outer Cuttings

How BEMA Designs the Flight Blank

Screw flights with outer cuttings require a specially engineered flight blank. Because the outer diameter is interrupted by cut‑offs, the blank cannot be formed using a standard circular template. BEMA designs a custom blank geometry that compensates for the missing material at the perimeter, ensuring that the final formed flight maintains correct pitch, helix angle, and structural strength. This design step is essential to avoid deformation during pressing and to ensure the cut‑offs align perfectly after forming.

Forming Process for Hardox and Stainless Steel

These screw flights are produced in Hardox 450 and stainless steel 1.4301/AISI‑304, two materials that behave very differently during forming. Hardox requires controlled force and precise tooling to avoid cracking at the cut‑off edges, while stainless steel demands careful handling to prevent distortion. BEMA uses specialized forming presses and material‑specific tooling to shape each segment accurately, even with the weakened outer geometry caused by the cut‑offs.

Maintaining Pitch Accuracy With Interrupted Outer Diameter

Outer cuttings make it more difficult to maintain a stable pitch during forming because the missing perimeter material reduces the natural stiffness of the flight. BEMA compensates by using reinforced forming fixtures that hold the blank in position throughout the press cycle. This ensures that the pitch remains uniform and that the screw flight fits correctly on the shaft during assembly.

FAQ on How BEMA Manufactures Screw Flights With Outer Cuttings

1. How does BEMA design screw flights with outer cuttings?

BEMA develops a specially engineered flight blank to compensate for the removed material on the outer diameter. Because the Hardox‑450 segments include cut‑offs, the blank must be designed so the flight maintains correct pitch, helix shape, and structural strength during forming.

2. What materials can BEMA manufacture these flights in?

The screw flights are produced in Hardox 450 and stainless steel 1.4301/AISI‑304, both selected for durability and wear resistance. These materials require different forming forces and handling techniques, which BEMA accommodates through specialized tooling and controlled manufacturing processes.

3. How does BEMA ensure quality and dimensional accuracy?

The forming process is adapted to the weakened outer geometry caused by the cut‑offs, ensuring the pitch remains stable and the flight fits correctly on the shaft. Each segment undergoes dimensional checks before shipment to ensure it maintains shape during long‑distance transport.

4. Can BEMA deliver screw flights globally without transport issues?

Yes. BEMA has established reliable partnerships with trusted transport companies and ships screw flights worldwide—including customers nearly 9,000 km away. The flights are easy to handle, and the risk of transport damage is very low, making them suitable for long‑distance delivery.