Parkway-Kew Corporation North Brunswick, New Jersey

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1 Parkway-Kew Corporation North Brunswick, New Jersey 1

2 Wire companies continually struggle with the age old dilemma of price versus quality. Now they can have the best of both worlds, and gain a competitive sales advantage. Increased production output by increasing machine speeds and drawing efficiency. Improve and maintain wire quality through the proper use of coatings for capstans, pulleys, and tuner and guide rolls. The application of common sense feedback recorded on the performance of the capstans on a wire drawing machine. 2

3 Preference for the status quo for the contours of wire drawing blocks by long time machine operators, and wire mill supervisors. An over reliance on the wisdom of OEM s for block configuration. Reluctance to accept, and continue to incur the cost and inconvenience of the trial and error method, which is required to establish the optimum tapers and contours that will maximize speed and production output. 3

4 One high carbon wire mill in the Southeastern U.S. sent an entire line of 900mm blocks from one of their nine hole Frigerio wire drawing machines to be repaired and hard-surfaced. 4

5 The interior of the block, and the inner core were also grit-blasted and coated with aluminum to prevent the build-up of rust and corrosion, and ultimately to improve the heat transfer. BEFORE AFTER 900MM Frigerio Double Deck Block 900MM Frigerio Double Deck Block 5

6 The cost for this work was $76,000. The ROI (Return On Investment) for this customer was three months. The end result was a significant increase in production due to the increased speed that the drawing machine was now able to achieve. 6

7 The results were so dramatic, that this very same customer a couple of months later sent another entire line repair and coating, only this time they were 1200mm Frigerio capstans. Although it is impossible to predict exactly how much of a production increase any wire drawing machine can achieve, increases of 20% to 50% would not be uncommon provided the motors and gearing are capable of the increase. 7

8 The most dramatic improvements are found on the high carbon drawing machines by improving the water cooling, and optimizing the contour of the capstans. Continuous drawing machines show the most improvement in productivity. However, the same principle also applies to one, two or three position machines. Machines that produce only one type of wire make the process easier and quicker. However, machines drawing a wide range of wire types will take longer, and may require some compromises. 8

9 Examine the condition of the blocks and the machine. Are there any significant grooves? Do all the intermediate blocks have the same taper? GROOVES 9

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13 Check the condition of the interior of the blocks along with any inner cores (if so equipped) for excessive rust and corrosion. Is the water cooling functioning correctly at each position on the machine? Are there any clogged pipes due to poor filtration or hardwater? Are there any broken pipes? 13

14 After the machine has warmed up, and reaches running temperature, use an infra red temperature gun pointed at the wire at the draw line to record the wire temperature at each position for each different wire being drawn. Record the speeds and production output for wire product to establish a baseline. 14

15 Establish a baseline where the water cooling is working well in all block positions. All tapers are known or have been established. There is no significant grooving on any block. The speed, temperature and production data has been recorded for all wire products. 15

16 Optimally, to achieve this goal may require regrinding all blocks from a single machine, (to remove grooves in the radius), and without coating them to establish a uniform taper. Practicality may dictate a less aggressive approach in sending all the blocks from one machine. Especially, if wire production needs to be maintained. 16

17 Assumes the first priority has been achieved (ie. the water cooling is working well in all block positions, all blocks are in good shape, and a baseline has been established for all wire products drawn). Turn the wire speed up in increments of 5%, and observe where any problems arise. The problems should occur at the extremities of the machine, either the first or last intermediate block, OTO block, stripper block, or a dead block. 17

18 Types of problems: Wire overlapping The wire moves up the face of the block, and then begins to crossover the previous wrap. 18

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20 Wire Separation (Two Types): Slinky Effect The wire moves up the face of the block with continuous separation between each proceeding wrap. This is referred to as the wire climbing like a Slinky, and usually indicates too much taper. 20

21 Jumping The wire moves up the face of the block normally, then suddenly jumps up the block face is small groups of wire very quickly. This usually indicates too little taper. Wire Jumping 21

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24 Corrections Make corrections to the problem block, and record the feedback. Turn up the speed, or make additional corrections to the block in that position, or others. For an intermediate block, take the corrected block, or one with the same corrected taper, and move to the opposite end of the machine. If it performs satisfactorily in that position at the higher speed, repeat the process. 24

25 Should an intermediate block located in a middle position fail to function properly at higher speeds, it should be modified to the correct taper of the blocks at the ends of the machine. OTO, Dead and Stripper blocks must be adjusted individually, if necessary. The goal with intermediate blocks is to have one contour, so the blocks are interchangeable. However, in one study, a nine-hole Morgan machine had to be modified so that each group of three blocks (beginning, middle and end had a different contour to maximize production. 25

26 Radius The radius has little value in solving wire climbing problems. The general rule is: the radius should be slightly larger than the largest wire being drawn. Radius The radius might be too small if the wire overlaps immediately at the radius. The radius might be too large if you are having problems with cast and helix. 450mm Double Deck Block 26

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28 Single taper Advantage simplicity Sometimes used as a compromise (taper averaging) for a double taper when repair shops lack the equipment or experience required to grind this taper. Not recommended results in poor performance. Single Taper 28

29 Double Taper (Conventional) Double Taper (Conventional) Larger taper transitioning to smaller taper. This contour helps handle the heat transfer during cold start-up, and reduce the heat build-up from continuous operation. Eliminates the need to turn off water cooling during start-up. 29

30 Double Taper (Non-Conventional) Smaller taper, then larger taper. This contour helps in reducing overlapping, especially with large stripper blocks. Double Taper (Non-Conventional) 30

31 Steps The reduction in diameter compensates for the wire cooling. The step or multiple steps facilitate the wire climbing, and allows for larger bundles with stripper blocks Steps 31

32 Overlapping Single Taper Increase taper. Change contour to include a step or nonconventional taper. Double Taper (Conventional) Increase taper at point of overlap. Extend length of first taper. Increase second taper. 32

33 Stepped Contour Increase taper at point of overlap. Increase the size of the step, but not more than two-thirds the diameter of the smallest wire. Double Taper (Non-Conventional) Increase taper at point of overlap. Shorten the length of the first taper. Increase second taper. Create a step contour. 33

34 Wire Separation Sometimes difficult to diagnose. Slinky Too much taper. Jumping in groups Too little taper. Apply the corrections as overlapping if wire jumps in groups. Apply opposite corrections as overlapping if wire is climbing like a slinky. 34

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36 Wire Marking Causes Wire too tight - Adjust taper. Broken Die Scratches or Marks on block Galling: Wire material depositing on block surface, causing subsequent marking. Slots marking - Round or bevel the edges of the slots. If this does not correct the problem, then it may be due to overdrafting. The solution may have to do with dead blocks (inverted or conventional). 36

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38 Grooves - The solution would be to hardsurface (coat) with a wear resistant coating (ex. tungsten carbide) to help maintain the proper taper, and increase the interval for the development of grooves. Faster speeds will increase capstan wear, resulting in a hard-surfacing (coating) becoming a necessity, rather than a luxury. Proper selection of a coating for the specific type of wire and lubricant is very important. 38

39 Galling Pieces of the drawn wire adhere to the block and mark the subsequent wraps of wire. Solutions include: Increase the taper. Change or increase the amount of lubricant with a lubricant applicator. Check for raised edges in the coating, which can cause shaving of the wire, and result in galling. If found, use a small grinder or belt sander to knock off the raised edges below the drawing surface. 39

40 Random marking Check for burrs on block face, posts, come-along holes, and stripper slots. Check condition of tuner and guide rolls, and dancer and turn-around pulleys. These should also be coated to eliminate wire marking. Check for bad or broken dies. 40

41 The key factors to increasing production output, and drawing efficiency, while improving and maintaining quality wire are: Keen observation Accurate record keeping Good feedback Making the right corrections Monitoring water cooling Utilizing these simple common sense fundamentals on most, if not all of your wire drawing machines, will put you on track to achieve both price and quality, while gaining a competitive advantage in the market place. 41