Coil Feed Systems

1. Coil Feed Systems Bruce Grant Coe Press Equipment Corp.

2. Agenda • Coil Feed Systems • Considerations For Selection • Unwinding • Straightening • Slack Loops • Feeding • Question And Answer

3. Coil Feed Systems Variety Of Solutions Selection Determines: • Versatility • Productivity • Floor Space

4. Speed Requirement Floor Space Purchase Price Energy and Maintenance Cost Safety Coil Weight Range of Materials Material Finish Run Time Between Reloading Loading/Threading Time Considerations For Selection

5. System Components • Uncoiler • Straightener • Slack Loop • Feed

6. Uncoiler Types • The 3 most common types of uncoilers. Coil Cradle Pallet Reel Centering Reel

7. Coil Cradle: Concept • The Coil Is Supported On Rollers • Medium to Heavy Gauge Materials • Materials Not Sensitive To Marking

8. Coil Cradles - Advantages • Coil Weight prevents clock-spring. • Unlimited weight capacity. • Payoff speed does not vary as coil diameter changes.

9. Coil Cradles - Disadvantages • Marking and distortion of thin or cosmetically sensitive materials. • Not suitable for rewinding and re-banding partially run coils.

10. Coil Cradles - 2 Basic Styles • Inline Style • Combination Style

11. Inline Style Cradle • Unwinds coil from the bottom. • Payoff is away from the press. • Easier to thread.

12. Inline Style Cradle • Space Saver • Overhead loop uses vertical space instead of floor space

13. Combination Style Cradle • Unwinds coil from top. • Pays off through a powered straightener into conventional loop.

14. Combination Style Cradle • Unobstructed access for loading. • Allows use of a load ramp for fast coil change.

15. Combination Style Cradle • Threading • More difficult to thread thick or high strength • Floor Space • Requires more floor space due to its conventional loop configuration.

16. Pallet Reels: Concept • Coils are stacked on a turntable and unwound laying on their side

17. Pallet Reels: Applications • Narrow material • Thin material • Low strength material • Where marking is not a concern

18. Pallet Reels: Advantages • Loading • Coils can be stacked • No need to upend narrow coils • Space Saver • Loop is contained around and above coil and does not use much floor space.

19. Pallet Reels: Disadvantages • Limited material Width Capacity • Strip must transition from vertical to horizontal • Payoff Rate Changes With Coil Diameter

20. Pallet Reels: Disadvantages • Clock spring Danger • Limited to light gauge, low strength materials • Threading aides for thick or high strength material are not normally available YOW!!

21. Centering Reels: Concept • Coil is held by its inside diameter • Most common method of unwinding • Available in a variety of configurations

22. Centering Reels: Applications • Can accommodate a wide variety of materials • No contact with outer wraps of material as unwound • Great for non-marking applications

23. Centering Reels • Options available to safely and effectively thread thick or high strength material. • Allows rewinding, banding and removal of partially run coils. Hold Down With Motorized Wheel Breaker Clockspring Guard Peeler

24. Centering Reels: Powered • Motorized units with loop control for payoff into slack loop. • Used where straightening is not required or can be used with pull through straighteners or feeder/straightener units.

25. Centering Reels: Non-Powered • Known as “Pull Off Reels” • Pinch rolls or powered straightener pulls material off coil • Requires a drag tensioning device prevents coil overrun

26. Centering Reels: Stationary • Fixed position. • Coil must be centered on mandrel when loaded.

27. Centering Reels: Traveling • Reel runs on a track • Allows realignment after the coil has been loaded and threaded. • Can run multiple coils

28. Centering Reels: Double Ended • Great for quick coil changes • Great for running partial coils • Requires more floor space

29. Dual Cone/Double Stub Arbor • Used for very heavy or very wide coils, with small inside diameters. • Support at both ends prevents mandrel deflection. • Can reposition coil after threading

30. Straightening • Purpose • To remove unwanted material shape defects • Requirements • Vary per application depending on the material defects present, the design of the die and the finished part requirements.

31. Straightening: Concept • Bend the material around sets of rollers to alternately stretch and compress the upper and lower regions to exceed the yield point so that all surfaces are the same length after spring back.

32. Straightening: Concept • Strain • Elastic Modulus • Stress • Elastic Limit • Yield Point • Springback

33. Straightening: Coil Set • The result of winding strip into a coil • Length difference between top and bottom surfaces • Results in curved shape

34. Straightening • Effectiveness is a function of roll center distance, number of rolls and power available

35. Straightening: Methods • Precision Leveler • Straightener

36. Precision Leveler • Material Conditions Corrected • Coil Set • Edge Wave • Center Buckles • Crossbow • Coil Breaks • Deep Stress Relief

37. Precision Leveler • 19 to 21 work rolls • Small diameter rolls • Very close roll center distance • Adjustable flights of backup rolls

38. Straightener/Flattener • Removes coil set and minor crossbow only • Typically 5 to 11 work rolls • Larger roll diameter • Wider roll spacing • Backup rolls not adjustable

39. Straightener/Flattener • Available in various roll configurations • 5, 7, 9 and 11 roll versions • Additional roll sets allow running entire coil without readjustment of straightening rolls

40. Straightener/Flattener • Pull Through Straighteners • Non-driven rollers • Located after the loop • Material is pulled through the straightener by the feeder • Powered Straighteners • Driven rollers • Located before the loop • Often used to pull material off of the coil

41. Straightener: Pull Through • Inexpensive and compact • Allows shorter loop length

42. Straightener: Pull Through • Pull Through Straightener Disadvantages • Material marking • Slippage and inaccurate feed lengths • Requires power from the feeder for straightening. • Limits material capacity • Decreases feed speeds • Less effective pilot release

43. Straightener: Powered • Advantages: • Less marking • Higher production speeds • Greater material capacity • Straightener/Feeders

44. Slack Loop: Purpose • Material storage to supply the feed while the unwinder accelerates to line speed • To absorb and store material while the coil decelerates after feeding stops • To allow the coil to run at a constant speed

45. Slack Loop • Types • Horizontal • Overhead • Paddle Horizontal Loop OverheadLoop Paddle Loop

46. Slack Loop • The amount of material stored is equal to the total slack length minus the straight line length. Straight Line Length Slack Length

47. Slack Loop • If the material is straightened prior to the loop then the radius of the loop cannot be smaller than the Minimum Bend Radius for the thickest material that will be run on that line.

48. Slack Loop • The strip must be supported into and out of the loop by cascade rolls at both ends. • Without support the weight of the loop will cause the material to be bent beyond its minimum bend radius resulting in material that is no longer flat.

49. Feeds: Types • Gripper Feeds • Roll Feeds • Press Driven • Servo Driven • Straightener/Feeder

50. Feeds: Gripper • Uses linear motion to move the strip • Uses clamping mechanisms to hold and move the strip