Abstract:
A system for pulp bale wrapping includes at least one press plate operable to press a wrapper into a pulp bale. A method for wrapping pulp bale includes disposing the pulp bale between an upper wrapper and a lower wrapper, wrapping the pulp bale in the upper wrapper and the lower wrapper, and maintaining at least one of the upper wrapper and the lower wrapper in a wrapped position by crushing the at least one wrapper into the wrapped pulp bale.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This Application claims the benefit of priority to U.S. Provisional Application Ser. No. 61/048,650, entitled “System and Method for Wrapping a Pulp Bale”, filed on Apr. 29, 2008, and which is incorporated herein by reference for all purposes. 
     
    
     BACKGROUND 
       [0002]    Pulp producers typically prepare large bales of pulp, wrap the bales of pulp, and hold the wrapping in place using metal straps. Such metal straps are problematic as they must be cut and disposed of before the bale of pulp is introduced into the paper making process. Cutting the metal straps and disposing of the waste costs time and money. 
         [0003]    Paper straps have been considered for use as a replacement for the current metal straps. Unfortunately, paper straps have not proven strong enough to withstand contact with the forks on equipment handling the wrapped bales. In particular, paper straps traversing the bale perpendicular to the forks are prone to breakage. Such breaking leaves strap portions which must be discarded. 
         [0004]    Hence, there exists a need in the art for advanced systems and methods for wrapping pulp bales. 
       SUMMARY 
       [0005]    Embodiments of the present invention provide for wrapping a pulp bale using one or more paper straps in a manner that avoids interference of handling equipment forks with the paper straps. Wrappers are inserted into opposite sides of the pulp bale to mechanically affix the wrapper to the pulp bale. Insertion of the wrappers may involve crushing the wrappers into the pulp bale using insertion apparatus of one or more shapes. Insertion apparatus may be active or inactive components. The pulp bale is rotated ninety degrees and one or more paper straps are strapped around the pulp bale. Forks of handling equipment may then be extended under the wrapped pulp bale in a direction substantially parallel to the paper straps. The wrapped pulp bale, including wrappers and paper straps, can then be placed in a pulp making vat. 
         [0006]    An embodiment of a method for wrapping pulp bale includes disposing the pulp bale between an upper wrapper and a lower wrapper, wrapping the pulp bale in the upper wrapper and the lower wrapper, and maintaining at least one of the upper wrapper and the lower wrapper in a wrapped position by crushing the at least one wrapper into the wrapped pulp bale. The method may further include binding the wrapped pulp bale with at least one paper strap. Binding the wrapped pulp bale may include orienting the at least one paper strap in a direction substantially parallel to forks of handling equipment. Binding the wrapped pulp bale may include positioning the paper straps at a distance from each other that is different from a distance between the forks of the handling equipment. The at least one paper strap may be oriented in a single direction. 
         [0007]    In an embodiment of a method, crushing the at least one wrapper into the wrapped pulp bale may include applying press plates to opposing sides of the pulp bale. Crushing the at least one wrapper into the wrapped pulp bale may include lifting a portion of the pulp bale to allow for insertion of the at least one wrapper into the pulp bale. Crushing the at least one wrapper into the pulp bale may further include placing a pressure element on top of the pulp bale to prevent flexing of the pulp bale during crushing of the pulp bale. Applying press plates to opposing sides of the pulp bale may include pressing one or more insertion apparatus into the upper wrapper and the lower wrapper. The one or more insertion apparatus may include one or more active components. The method may further include rotating the pulp bale to orient the at least one paper strap in the single direction. 
         [0008]    A system for pulp bale wrapping includes at least one press plate operable to press a wrapper into a pulp bale. The at least one press plate may comprise a pair of press plates operable to be applied to opposing sides of the pulp bale to crush the wrapper into the pulp bale. The at least one press plate may include at least one insertion apparatus configured to crush the wrapper into the pulp bale. The system may further include at least one paper strap binding the wrapper around the pulp bale in a single direction. The single direction may be substantially parallel to forks on handling equipment. The at least one paper strap may include two paper straps positioned at a distance from each other that is different from the distance between the forks. 
         [0009]    In an embodiment of a system the at least one press plate may include multiple insertion apparatus, wherein each of the insertion apparatus has a shape. At least two of the insertion apparatus may have a different shape. One or more of the insertion apparatus may be active components. The system may further include a lifting mechanism operable to lift at least a portion of the pulp bale while pressing of the wrapper into the pulp bale. The system may further include multiple wrappers that include a lower wrapper disposed beneath the pulp bale and an upper wrapper disposed on top of the pulp bale. 
     
    
     
       DESCRIPTION OF DRAWINGS 
         [0010]      FIG. 1  is a flow diagram depicting a process for pulp bale wrapping in accordance with various embodiments of the present invention; and 
           [0011]      FIGS. 2   a - 2   f  depict an exemplary pulp bale at different stages of the processing described in relation to  FIG. 1 . 
           [0012]      FIGS. 3   a - 3   f  depict example shapes of insertion elements that can protrude from compression plates. 
           [0013]      FIGS. 4   a - 4   b  depict example compression plates with elongate insertion elements that may be used in during insertion or retraction of the insertion elements. 
           [0014]      FIG. 5  illustrates another embodiment of an insertion element in which active component eject from the insertion element. 
       
    
    
     DESCRIPTION 
       [0015]    Embodiments of the present invention provide for wrapping a pulp bale using one or more paper straps in a manner interference of handling equipment forks with the paper straps. Wrappers are inserted into opposite sides of the pulp bale to mechanically affix the wrapper to the pulp bale. Insertion of the wrappers may involve crushing the wrappers into the pulp bale using insertion apparatus of one or more shapes. Insertion apparatus may be active or inactive components. The pulp bale is rotated ninety degrees and one or more paper straps are strapped around the pulp bale. Forks of handling equipment may then be extended under the wrapped pulp bale in a direction substantially parallel to the paper straps. The wrapped pulp bale, including wrappers and paper straps, can then be placed in a pulp making vat. 
         [0016]    Turning to  FIG. 1 , a flow diagram  100  depicts a process for pulp bale wrapping in accordance with various embodiments of the present invention. Following flow diagram  100 , a pulp bale is received (block  100 ). A representation of a pulp bale  200  is depicted in  FIG. 2   a.  A typical pulp bale  200  consists of a large number of sheets  202  of pulp stacked one atop another creating a rectangular brick of pulp. When received, the sides of the pulp bale  200  appear as a stack of sheets while the top and the bottom appear as a solid sheet of pulp (i.e., the top sheet and the bottom sheet). A lower wrapper is placed under the pulp bale and an upper wrapper is placed on top of the pulp bale (blocks  110 ,  115 ). Both the upper and lower wrappers may be formed as a sheet of pulp cut of a size that allows it to be folded over and cover at least a portions of the sides of the pulp bale. 
         [0017]    A representation of an upper wrapper  204  and lower wrapper  206  disposed in relation to pulp bale  200  is depicted in  FIG. 2   b.  The upper wrapper  204  and the lower wrapper  206  are folded to cover two opposing sides (block  120 ). In some cases, the upper wrapper and lower wrapper overlap along the sides.  FIG. 2   c  shows the result of folding  208  upper wrapper  204  and lower wrapper  206  over the opposing sides of pulp bale  200 . Folding  208  may be facilitated with use of a mechanical apparatus. Folding  208  of the upper wrapper  204  and the lower wrapper  206  is not limited to any particular order; that is, the upper wrapper  204  may be folded first, followed by folding of the lower wrapper  206 , or vice versa. 
         [0018]    The upper wrapper  204  and the lower wrapper  206  are then mechanically crushed into and/or between the sheets of pulp in the pulp bale (block  125 ). This process is depicted in  FIG. 2   d  where two opposing press plates  210 ,  212  act on the bale  200 , upper wrapper  204  and lower wrapper  206 . Each of press plates  210 ,  212  include one or more insertion apparatus  214  that press/crush upper wrapper  204  and lower wrapper  206  into/between sheets  202  of pulp in pulp bale  200 . The one or more insertion apparatus  214  can be protrusions from the press plates  210 ,  212 . There can be any number of insertion apparatus  214 , and the insertion apparatus  214  can be located at a number of different places on the press plates  210 ,  212 . In some cases, insertion apparatus  214  are positioned so that they insert both wrappers  204 ,  206  into the pulp bale  200  when compressed. 
         [0019]    The shape(s) of insertion apparatus  214  is not limited. In  FIG. 2   d,  the insertion apparatus  214  are substantially “V” shaped, but this is not required. For example, the insertion apparatus  214  can take on multiple different shapes, including, but not limited to, concave, convex, circular, rectangular, “M” shaped, “U” shaped, “W” shaped, and so on. Multiple different shapes can be used simultaneously.  FIGS. 3   a - 3   f  illustrate numerous exemplary shapes of insertion apparatus  214  than can be formed on the plates  210 ,  212 . The shape may be selected depending on the crushing process that is used. 
         [0020]    The crushing or compressing process (block  125 ) generally involves the plates  210 ,  212  pressing into the bale  200 , followed by a retraction or pulling away from the pulp bale  200 . The crushing process (block  125 ) can be carried out in numerous different ways to more or less secure the wrappers  204  and  206  within the pulp bale  200 . In either of the insertion or retraction steps, the plates  210 ,  212  can be moved forward and backward, laterally from side to side, and/or vertically up and down. For example, the plates  210 ,  212  may lift or drop when pulling away from the pulp bale  200 . 
         [0021]    To illustrate,  FIGS. 4   a  and  4   b  depict plates that have elongated insertion elements  402 ,  404  that may be used. For example, after insertion, the insertion elements  402 ,  404  may be lifted by one of the plates while being dropped by the opposing plate to force the wrapper on one side of the bale to be crushed up into the bale, while forcing the wrapper on the other side of the bale to be crushed down into the bale. In such a scenario, the lifting and dropping of the opposing plates can occur while the insertion elements  402 ,  404  are being retracted from the bale  200 . As such, lifting and dropping of the insertion elements  402 ,  404  can occur in conjunction with the insertion and/or the retraction of the insertion elements  402 ,  404 . 
         [0022]      FIG. 5  illustrates another embodiment of an insertion element  500  in which one or more active components  502  can eject  504  from the insertion element  500 . There may be any number of active components  502 , depending on the particular implementation. The active components  502  can eject after the insertion element  500  has been inserted into the bale  200  to thereby further force the wrapper(s) into the pulp sheets in the bale  200 . Ejection of the active components  502  may be trigger by spring loading or otherwise. Ejection of the active components  502  may be triggered by user input or by sensors that detect insertion of the insertion element  500 . Sensors could also trigger ejection  504  based on detecting movement or stopping of movement of the plate. For example, when the insertion element  500  stops moving forward, the sensors could trigger ejection. 
         [0023]    In some cases, a weight or other pressure element is placed on top of pulp bale  200  to keep it from flexing while press plates  210 ,  212  press insertion apparatus  214  into pulp bale  200 . By crushing upper wrapper  204  and lower wrapper  206  into pulp bale  200 , the fold(s) of the wrappers is maintained in place for at least the period required to finish wrapping pulp bale  200 . 
         [0024]    It should be noted that other variants of the invention are possible. For example, a top part of the pulp bale  200  may be lifted somewhat by a lifting mechanism, allowing for the wrappers to be inserted between sheets  202  of pulp before the top part of the pulp bale  200  is let go and the pressure of the pulp holds the reinserted wrappers in place. One example of a lifting mechanism are forks of a forklift. 
         [0025]    With the upper wrapper and lower wrapper fixed, the pulp bale is turned ninety degrees (block  130 ). This turning process  215  is depicted by  FIG. 2   e.  In addition,  FIG. 2   e  depicts crush insertions  216  of upper wrapper  204  and lower wrapper  206  into pulp bale  200  that were created in the previous process (block  125 ). With the bale turned ninety degrees (block  130 ), the remaining open ends of pulp bale  200  are covered by folding upper wrapper  204  and lower wrapper  206  over the ends (block  135 ). This process is depicted in  FIG. 2   f.  The recently folded ends are then bound by one or more paper straps  218  to hold the folds in place (block  140 ). The binding process is depicted in  FIG. 2   g  where straps  218  are wrapped around pulp bale  200  in a single direction. After the binding process, the pulp bale  200  is fully wrapped. 
         [0026]    With further regard to the binding process (block  140 ), the binding process may involve positioning the paper straps  218  at a selected distance from each other and in a single selected direction. The selected distance and direction may depend on the distance between forks  220  of handling equipment and the orientation of the forks  220 . For example, the distance between two paper straps  218  may be different from the distance between the forks  220  so that the forks do not rub the paper straps  218 . Of note, because paper straps  218  go in a single direction, they are less likely to be interfered with by the forks  220  of handling equipment, where the handling equipment grabs pulp bale  200  such that the forks  220  to not extend perpendicular to straps  218 . For example, forks  220  are directed at the bale  200  in a direction substantially parallel to the straps  218 . The pulp bale  200  together with wrappers and paper straps may then be placed together in a pulp making vat. 
         [0027]    With more specific regard to the paper straps  218 , paper straps may be formed in numerous different ways. By way of example, and without limitation, paper straps and methods for creating paper straps are shown and described in U.S. Pat. No. 7,118,684, entitled “Paper Strap”, issued on Oct. 10, 2006 to Edward Dever, et al, sharing a common assignee herewith, and which is incorporated herein by reference for all purposes. 
         [0028]    Embodiments of the invention have now been described in detail for purposes of clarity and understanding. However, it will be appreciated that certain changes and modifications may be practiced within the scope of the appended claims. Accordingly, it should be recognized that many other systems, functions, methods, and combinations thereof are possible in accordance with the present invention. Thus, although the invention is described with reference to specific embodiments and figures thereof, the embodiments and figures are merely illustrative, and not limiting of the invention. Rather, the scope of the invention is to be determined solely by the appended claims.