Technology

The patented cutting process by PTZWEIDNER
THE GIANT RING CUTTER

RAW MATERIAL	CUTTING PROCESS	RESULT

Special Process Features

The GIANT RING CUTTER by PTZWEIDNER initially uses gripper arms to transport the raw material to the chuck. Three chuck jaws driven by a ball screw drive secure the ring in the cutting position during the rotating cutting motion, ensuring a clean cut. Ball screw drives perform highly accurate feeding, positioning and transportation tasks with precision leadscrews, pre-tensioned anti-backlash adjustable single and double-nuts. The rigid roller guide rails reduce vibrations sufficiently that the emitted noise is limited to 70 to 74 decibels, even on the open version.

The circular sawblade has a diameter of 500 mm and cuts diameters up to 9,000 millimeters and wall thicknesses up to 300 millimeters at only a 3 mm kerf loss. The low chucking height and the high precision of the process facilitate accurate cutting up to a ring height of only 8 mm. The automation concept with the gripper arm is designed for ring diameters of four to eight meters and ring weights of up to 20 tons.

» Process picture gallery 

The benefits are apparent

Significant cost and quality benefits

• up to 90% reduced cutting cycles and energy consumption
• up to 60% material savings due to reduced kerf loss
• up to 40% tool cost savings due to increased tool life
• increased plane parallelism and surface finish quality
• reduced downstream processing requirements

Benefits with respect to accident prevention / occupational safety / environmental protection

• safe and reliable holding, removing and automatic placement of cut rings / tubes
• cut creates short chips and a minimal burr
• very low thermal exposure, no burning hazard
• low cutting noise and reduced cutting tool consumption

A versatile plant concept facilitates retrofit options for already installed revolver lathes and milling machines.
 

Calculation example

A customer needs 14,400 rings per year

Conventional processing:
4 rings from one blank
3,600 blanks - 115,200 kg material weight

Using the GIANT RING CUTTER:
5 rings from a shorter blank
2,880 blanks - 86,400 kg material weight

Material savings: 28,800 kg
material cost reduction: EUR 1,000,000 / year (at a material cost of EUR 38 / kg) 
 

 
Comparison to conventional methods

In the past, metal rings have been produced either on ring rolling mills, or by cutting on revolver head turning lathes, or by cutting on band or circular saws. Until now, these processes have been subject to high tool wear, enormous energy consumption and immense loss of material - it was therefore high time for an efficient cutting process to cut rings from raw material stock.

Milling	Lathe-cutting	Saw-cutting
Minimum milling height is specified Shape stability problems Needs large machining allowance	Low ring wall-thickness possible Long cutting cycles Long chips » accident hazard Rings cannot be held in a controlled manner	Large cutting variance Large material allowances needed High time requirement Damaged cutting surface finish from chips High tool costs

» We will gladly demonstrate our process! Feel free to contact us!