Abstract:
Systems and methods which provide improved pipeline mats are provided herein. Such mats may include one or more of a plurality of the inventive features. For example, some embodiments provide for replaceable top surfaces which allow for portions of the mat to be replaced if in need of repairs, e.g. after excessive wear and tear, rotting, and the like. Further, embodiments may include a built-in air wick channel which allows for airflow to travel between stacked mats, thereby reducing the potential for a mat to rot. Some embodiments may also include a structure which allows for the mat to be moved using a forklift. Such structure may include grouser strips which help direct the forklift while also protecting the top surface from wear. Additionally, such structure may include built-in chocks disposed on the lower surface of the mat. These chocks may also facilitate the air wick channel.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Patent Application No. 61/639,758, filed Apr. 27, 2012 and entitled, “IMPROVED PIPELINE MAT,” the disclosure of which is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present description relates generally to pipeline mats, and more specifically to systems and methods to provide for reusable/durable pipeline mats which are easily transported and deployed. 
       BACKGROUND 
       [0003]    There are generally two kinds of mats that are used in the pipeline business. One is called a pipeline, crane or bridge mat, which consists of 8 in. by 8 in. timbers, usually six of them bolted together to make a 48 in. by 18 ft. mat. The mat is held together with I-bolts with a tie rod in the end for lifting. 
         [0004]    The deficiency with this design is that it is made primarily of wood, such as untreated wood, which comes in contact with the ground and moisture. Once the mats have been used in the field, the wood is generally moist and at that point they are stacked for storage. The moist wood of the mats is stacked together with no little or no air circulation between the units, which usually causes accelerated rot. 
         [0005]    In addition, it is difficult to move the stacks of mats, which are generally moved by forklift. There is no gap between the mats to insert the forks of the forklift unless one manually inserts a spacer or chocks between each mat when stacking. These mats are used in large quantities on project sites, and it is not cost effective to have a person manually placing spacers between several thousand mats when stacking for storage. 
         [0006]    Another type of mat used in an oilfield is called a laminated mat, constructed of 2 in. by 8 in. boards to make an 6 in. by 8 ft. by 12 or 14 ft. section. There are gaps in between the sections. Again, the mats are constructed almost entirely of wood and have the same drawbacks associated with the other design. 
         [0007]    In addition, because the mats are constructed of wood fastened together, one cannot easily repair or replace the individual sections of the mats in the field. Wear from continued use and/or damage from heavy equipment used in the field can cause individual pieces of wood used to construct the mats to disintegrate and fall from the constructed mats. This disintegration causes loss of compression and torque of the tie rods holding the unit together. It also makes the mat no longer useable. 
         [0008]    Once compression is lost, the grouser, the teeth on the tracks, will get in between the remaining pieces of the wood and pull the mat apart, thereby destroying the unit. There is no edge protection on the current mats in use, and there is no way to refill or repair the mats in the field. In order to refurbish existing mats, they must first be removed from the oilfield, and then the missing wood may be replaced. This replacement of missing wood generally requires the entire unit to be disassembled prior to repair. 
         [0009]    In addition, harder lumber is generally used for laminate pieces of a mat, and softer lumber is used for the interior construction. Once the harder outer lumber is destroyed, the softer inner lumber is also no longer usable. Because of the difficulty and cost of repair, it is not usually cost effective to do so. Thus, mats in need of repair are simply discarded. Generally speaking, one can assume approximately a 40% loss of mats within the first 90-150 days of use in a pipeline project. 
       BRIEF SUMMARY 
       [0010]    Systems and methods which provide improved pipeline mats are provided herein. Such mats may include one or more of a plurality of the inventive features. For example, some embodiments provide for replaceable top surfaces which allow for portions of the mat to be replaced if in need of repairs, e.g. after excessive wear and tear, rotting, and the like. Further, embodiments may include a built-in air wick channel which allows for airflow to travel between stacked mats, thereby reducing the potential for a mat to rot. Some embodiments may also include a structure which allows for the mat to be moved using a forklift. Such structure may include grouser strips which helped direct the forklift while also protecting the top surface from wear. Additionally, such structure may include built-in chocks disposed on the lower surface of the mat. These chocks may also facilitate the air wick channel. 
         [0011]    The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims. The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    For a more complete understanding, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
           [0013]      FIG. 1  is an isometric exploded view of a pipeline mat in accordance with the present disclosure; 
           [0014]      FIG. 2(   a ) is a front sectional view of a pipeline mat in accordance with the present disclosure; 
           [0015]      FIG. 2(   b ) is a side sectional view of a pipeline mat in accordance with the present disclosure; 
           [0016]      FIG. 3(   a ) is a plan view of a pipeline mat in accordance with the present disclosure; 
           [0017]      FIG. 3(   b ) is a side view of a pipeline mat in accordance with the present disclosure; 
           [0018]      FIG. 4  is a partial exploded view of a pipeline mat in accordance with the present disclosure; 
           [0019]      FIG. 5(   a ) is a plan view of an end cap of a pipeline mat in accordance with the present disclosure; 
           [0020]      FIG. 5(   b ) is a front view of an end cap of a pipeline mat in accordance with the present disclosure; 
           [0021]      FIG. 5(   c ) is a side view of an end cap of a pipeline mat in accordance with the present disclosure; 
           [0022]      FIG. 5(   d ) is an isometric view of an end cap of a pipeline mat in accordance with the present disclosure; and 
           [0023]      FIG. 6  is an isometric view of a pipeline mat in accordance with the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]      FIG. 1  illustrates an exploded view of a pipeline mat  100  in accordance with an embodiment of the present application. The pipeline mat includes a slidably replaceable top layer material  102 . In one embodiment, the top layer material  102  is oak, however other embodiments may include other woods, laminate, or other suitable materials having stronger structural properties to accept the wear from the traffic, heavy equipment, and other materials that come in contact with the mat. 
         [0025]    Referring briefly to  FIG. 2(   a ), the top layer material  102  is held in place by an assembly including one or more restraints  200 . Returning to  FIG. 1 , this assembly may also include a back angle piece  104  disposed on one end of the pipeline mat  100 , and a removable end cap  106  configured to be disposed on the other end. In some embodiments, the top layer material  102  is not otherwise fastened to the structure, e.g. using bolts, screws, and the like. This assembly allows a user to remove the end cap  106  and easily replace damaged portions of the top layer material  102  while in the at the work site. The top layer material  102  may include extensions  108  on either end. In the present embodiment, an L-shaped extension is shown, which is used for slidably replacing a wooden piece within the assembly of a frame without need to bolt or otherwise fasten the top layer material  102 . 
         [0026]    In the illustrated embodiment, the end cap  106  is the retainer piece for the top layer material  102 . It is bolted to a front portion of the frame for the pipeline mat  100  and holds the edge of the wood in order to keep the wood compressed longitudinally from end to end. To replace damaged top material, the end cap  106  may be removed and the damaged top material may slide out and be replaced. 
         [0027]    The pipeline mat  100  also includes a bottom layer material  110 . Such a bottom layer material  110  is generally more exposed to the elements while the pipeline mat  100  is in use. This bottom material may be implemented using any material which will provide the structural support necessary to facilitate the functionality of the pipeline mat  100 . For example, some embodiments utilize sections of pine which are affixed within the frame of the pipeline mat  100 . In some embodiments this bottom section will be permanently attached. 
         [0028]    Referring generally to  FIGS. 1 ,  2 ( a ), and  2 ( b ), the pipeline mat frame has a lip portion  112  that is designed to capture the extension  108  from the top layer material  102 , and that also connects to the end cap  106 . In addition, the frame has an angled piece of metal at each corner which is the mating piece to the top layer material  102 , providing the cavity into which the top layer material  102  is inserted. This angled piece of metal is the restraint  200  of the assembly previously mentioned, and may be referred to as a wood restraint in embodiments in which the top layer material  102  is comprised of wood. The restraint  200  may extend continuously along the length of the frame except at the lip portion  112 . However, as will be discussed in greater detail below with respect to  FIG. 5 , extensions of the end cap  106  may be configured to continue or complete the restraint  200 . 
         [0029]    The frame may also include multiple pieces of guard railing  202 , such as flatbar, set at an angle (e.g., approximately 40°). These pieces of guard railing  202  may be attached at an angle to the restraint  200 . They may extend continuously along the length of the frame, or in some embodiments, they may extend up to the lip portion  112 , where the end cap  106  attaches to the frame. Functionally, these angularly attached pieces of guard railing  202  may serve as an edge protector for the pipeline mat (e.g., protecting the edge of the top layer material  102 ). 
         [0030]    In one aspect, the edge protector (e.g., guard railing  202  and/or restraint  200 ) serves as a grouser wear strip. For example, when the mat  100  is in use at the work site, multiple mats are typically placed side by side in an array 18 ft. wide. The length of the array is dictated by the requirements of the work site. When a tracked vehicle (grouser) approaches the array of mats, the tracks of the vehicle will often damage the material at the edge of the exposed mat. In accordance with the present disclosure, the restraint  200  of the metal frame, as well as the provided guard railing  202 , may be utilized to provide protection from this damage. As configured, the wood restraint  202  provides a structural support for the guard railing  202  to deflect the grouser from the edges of the wooden portions of the mat  100 . 
         [0031]    In another aspect, the edge protector serves as a fork slide to allow the forks of a forklift to be easily slid between two stacked mats for transport. For example, when the forks are inserted between two mats, they contact the edge protector and are deflected upwards into an upper half of an air wick channel  204  provided on an underside of the upper one of the mats. Together, the forkslide and air wick channel substantially prevent the forks from directly contacting the wood of the bottom layer material. This configuration facilitates sliding of one or more forks of a forklift into the open space between a plurality of mats, which are stacked upon each other, in order to lift one or more mats. 
         [0032]    In contrast, prior art mats are unable to be moved by forklift without the use of further components, such as spacers, because of the design as mentioned above. Existing mats are moved by a squeeze clamp attached to a track hoe, which clamps individual mats by the ends using friction compression and places them on the ground where needed. The difficulty with moving mats using this method is that only a single mat may be moved at a time. The mats of the present disclosure may individually be moved by this existing method, or one or more mats may be moved by forklift, which provides a significant time and cost savings to the user. 
         [0033]    In the embodiment shown in  FIG. 2(   a ), the bottom layer material  110  is held in place by S-beams  206 A and  206 B, which are similar to I-beams, but have flanges tapered at the top and bottom. The guard railing  202  may be angularly attached to the S-beams  206 A and  206 B, as well as to the restraint  200 . In some embodiments, welding may be utilized to attach the restraint  200  to the S-beams  206 A and  206 B, and also to attach the guard railing  202  to the restraint  200  and the S-beams  206 A and  206 B. It should be noted that the frame is comprised of the S-beams  206 A and  206 B, and that side cap plates  116 A and  116 B, as shown in  FIG. 1 , may be provided to the S-beams to prevent forks of a fork lift from being misdirected or caught by outer tapered flanges of the S-beams  206 A and  206 B. The use of the S-beams  206 A and  206 B creates the air wick channel  204  at the bottom of the mat  100 , and keeps the flat, lower surface of the bottom layer material  110  from direct contact with other mats when stacked. The tapered flanges engage extensions of the bottom layer material  110  that are configured to fit within a recess formed between the tapered flanges while permitting the upper surface of the bottom layer material to extend upwards and provide structural support for the top layer material during use. These extensions may be L-shaped, but other shapes are also contemplated, such as smoothly tapered extensions that match the tapers of the upper tapered flanges of the S-beams  206 A and  206 B. The tapered flanges function to retain a lower surface of the bottom layer material at a height above a bottom of the mat, thereby forming the air wick channel  204 . This configuration allows air flow and prevents rot caused by surfaces of wet boards directly contacting one another during storage. It should be understood that other embodiments are not limited to a particular structure, such as an S-beam, but may utilize any structure that provides the advantages of retaining the bottom layer material and providing spacing to create the air wick channel. 
         [0034]    In addition, metal pieces, such as the flat bar metal supports shown in  FIG. 1 , and referred to herein as chocks  114 , are fastened (e.g., welded, bolted, or riveted) to the bottom of the mat  100  to create an additional space underneath the bottom layer material  110 . In this manner, when multiple mats are stacked, air can freely flow between the units and allow the wood to dry between uses. This spacing apart of the mats also facilitates use a forklift to transport multiple mats. These chocks  114  also serve to provide traction or grip for the mats when in use, so that the mats do not slip against the ground underneath the grousers. It should be understood that the chocks  114  are not limited to flat bar metal supports, but may be composed of any structure that creates additional spacing for stored mats, and provides traction or grip for mats during use. 
         [0035]    Referring now to  FIG. 3 ,  FIG. 3(   a ) and  FIG. 3(   b ) respectively illustrate a top and a side view of the mat  100  shown in  FIG. 1 .  FIG. 3(   b ) provides a side view of the chassis without the top and bottom material in order to demonstrate placement of the chocks  114 , some of which are partially obstructed in  FIG. 3(   a ). The chocks  114  may have a height, such as ¼ or ½ of an inch. However, additional or alternative embodiments may utilize any size of chocks  114  while implementing the inventive aspects of the present disclosure. For example ¾ or even 1 inch chocks may be used. In fact, various design considerations, such as different materials being used, may lend themselves to utilizing different heights. It is noted that ½ inch chocks  114  are more readily available on the market at the current time. 
         [0036]      FIG. 4  is a zoomed in exploded view of the embodiment of  FIG. 1 .  FIG. 4  illustrates that the end cap  106  is removable. As can be seen, the top layer material  102  may be slidably inserted into the frame over the bottom layer material  110 . Upon insertion of the pieces of the top layer material  102 , the removable end cap  106  and may be reattached to the frame at the lip portion  112  thereof in order to secure the pieces of top layer material  102  in place. The lip portion  112  may be comprised of end portions of the S-beams  206 A and  206 B, a front side  400  of the frame, and a pair of horizontal, spaced apart slots, referred to herein as end cap pockets  118 , provided to the front side  400  of the frame. Spaced apart vertical members  404 A and  404 B of the end cap  106  may be configured to insert into these slots in order to facilitate positioning and retention of end cap  106  in a removable fashion. Fasteners  406 A- 406 D may be implemented in any manner suitable for securing the end cap  106  to the frame at the lip portion  112 . In the illustrated embodiment, fasteners  406 A- 406 D are shown as bolts. Fasteners  406 A- 406 D may be used to secure apertured extension flanges of the end cap  106  to the frame through apertures formed in the lip portion  112  at top surfaces of the S-beams  206 A and  206 B, and at recessed edges of the front side  400  of the frame. 
         [0037]    Referring generally to  FIG. 5(   a )- FIG. 5(   d ), multiple extension flanges  500 A- 500 D facilitate secure fitting of the end cap  106  with the pipeline mat. For example, the illustrated embodiment includes flanges  500 A- 500 B on both ends which allow for the end cap  106  to be bolted onto a top of the mat. The illustrated embodiment also shows flanges  500 C- 500 D extending downward from the front surface which are to be received on the front side of the mat, which may assist in securing the end cap onto the pipeline mat. Additionally, the end cap  106  may be provided with extensions  502 A and  502 B that may be configured to effectively continue or complete the wood restraint for the lip portion of the frame. 
         [0038]    It is noted that embodiments of the present application are not limited to any specific implementation of an end cap  106 , including any manner to attach or remove the end cap  106 . It is appreciated that the end cap  106  functions to retain the slidably replaceable top material. As such, an end cap  106  can be constructed in any manner to accomplish these ends. It is further noted that embodiments may utilize different structure to secure the top material. Such structure does not necessarily have to be located at the end of a mat. The invention is not necessarily limited to the particular end cap design illustrated in the figures. All that is required is a removable or repositionable piece to secure the top material and facilitate replacement thereof. 
         [0039]      FIG. 6  shows a completely assembled pipeline mat  100  in accordance with one embodiment of the present application. As shown in  FIG. 6 , the top layer material  102  includes a plurality of beams which are utilized to form the top surface. The end cap  106  is inserted into end cap pockets  118  on the front side  400  of the frame and bolted to the lip portion  112  of the frame of the mat  100  to longitudinally secure the top beams. The L-shaped portions of the top surface are locked down by the restraint  200  that traverses the length of the mat. Further,  FIG. 6  illustrates the angled guard railing  202  that serves as a fork slide that facilitates forklift transportation, and that also functions as a grouser wear strip when the mat is actually in use. Notably, the flat bar  202  may be discontinuous at the lip portion  112  of the frame to facilitate access to the bolts securing the end cap  106  to the frame. The L-shaped portion of the top surface allows the grouser wear strip to be attached or welded to the restraint  200 , and helps protect the edge of the wood from direct contact with the grouser to avoid damage. Side cap plate  116 A covers outer tapered flange regions of the S-beams and function to prevent forks of a fork lift from being caught or misdirected by the outer tapered flanges. 
         [0040]    Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the claims which issue from this application are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.