The required tonnage for an automatic channel steel punching machine is determined by channel‑steel wall thickness,hole size,hole quantity punched per stroke,and steel grade.It cannot be simply defined by a fixed value.Automatic channel steel punching machines are widely used for punching bolt holes and connection holes on guardrail posts,steel‑structure brackets and mechanical support components.Improper tonnage selection will result in incomplete punching,punch fracture,excessive burrs or even frame deformation during long‑term mass‑production.
The basic punching‑force calculation follows the blanking‑force formula:punching force equals hole perimeter multiplied by material thickness multiplied by material shear strength,plus a reasonable safety coefficient of 1.2‑1.3 to account for die wear and material fluctuation.For ordinary Q235 mild‑steel channel steel,which is the most common material for guardrail and steel‑structure accessories,practical tonnage reference ranges are widely adopted in the industry.For channel steel wall thickness below 6 mm,35‑45‑ton hydraulic punching force can satisfy single‑hole punching demands.When wall thickness reaches 8‑10 mm,60‑80‑ton models are recommended.For channel steel with wall‑thickness up to 12 mm,machines of 90‑120 tons are required to guarantee stable punching performance.
If multiple holes are punched in one single stroke,the total required tonnage increases correspondingly.Users must sum the cutting force of all holes and reserve sufficient safety margin.Servo‑feed automatic channel‑steel punching machines adopt sequential single‑hole punching mode in most cases,so they do not need extremely high instant tonnage,but the frame rigidity still needs to match the maximum wall‑thickness specification.
Material grade also exerts obvious influence.Hot‑dip galvanized channel steel has similar shear strength to ordinary carbon steel,so tonnage can be selected according to actual wall thickness.For high‑strength alloy channel steel,shear resistance rises significantly,so tonnage should be increased by 20%‑40%compared with Q235 under equal wall‑thickness conditions.It is worth noting that nominal tonnage is the maximum output force of the hydraulic system;long‑term continuous production should avoid running persistently near the upper‑limit load.
Besides hydraulic tonnage,supporting configuration cannot be ignored.Even with sufficient tonnage,insufficient frame rigidity will cause positioning deviation after long‑time vibration.Matching punch‑die sets must be selected according to wall‑thickness,otherwise burr defects will occur regardless of how high the tonnage is.Throat depth of the machine should adapt to channel‑steel section width,ensuring smooth feeding and avoiding workpiece interference.
In actual procurement,users should take the frequently‑processed maximum wall‑thickness and maximum hole size as design basis,not only the occasional extreme‑size workpiece.Sample test punching with real channel‑steel samples before formal order is strongly suggested to verify punching completeness and machine operating stability.
References
APA 7th
Gao,L.,&Liu,Q.(2020).Tonnage selection and structural optimization of hydraulic punching machine for channel steel profiles.*Journal of Physics:Conference Series*,1635(1),012048.
MLA 9th
Gao,Lei,and Qiang Liu.“Tonnage Selection and Structural Optimization of Hydraulic Punching Machine for Channel Steel Profiles.”*Journal of Physics:Conference Series*,vol.1635,no.1,2020,p.012048,
GB/T 7714‑2015
GAO L,LIU Q.Tonnage selection and structural optimization of hydraulic punching machine for channel steel profiles[C]//Journal of Physics:Conference Series.IOP Publishing,2020,1635(1):012048.
