Strengthened rig mat systems for supporting heavy loads

Abstract

A rig mat system includes a plurality of rig mats each comprising a rectangular frame and one or more billets supported by the rectangular frame, a link configured to releasably couple the plurality of rig mats together, the link including a link frame comprising a base plate having a plurality of laterally extending arms, and a plurality of connector assemblies releasably connectable to the plurality of arms of the link frame, wherein each connector assembly comprises an externally threaded fastener, an internally threaded nut configured to threadably connect to the externally threaded fastener, and a washer positionable about the fastener and having an elongate central aperture.

What is claimed is: 
     
         1 . A rig mat system, comprising:
 a plurality of rig mats each comprising a rectangular frame and one or more billets supported by the rectangular frame;   a link configured to releasably couple the plurality of rig mats together, the link comprising:
 a link frame comprising a base plate having a plurality of laterally extending arms; 
 a plurality of connector assemblies releasably connectable to the plurality of arms of the link frame, wherein each connector assembly comprises an externally threaded fastener, an internally threaded nut configured to threadably connect to the externally threaded fastener, and a washer positionable about the fastener and having an elongate central aperture. 
   
     
     
         2 . The rig mat system of  claim 1 , wherein the central aperture of the washer has a central axis which extends orthogonally to a central axis of the fastener. 
     
     
         3 . The rig mat system of  claim 1 , wherein:
 the washer of each of the plurality of connector assemblies comprises a radially inner washer; and   each connector assembly comprises an outer washer having a central aperture in which the inner washer is at least partially receivable.   
     
     
         4 . The rig mat system of  claim 3 , wherein the central aperture of the outer washer is at least partially defined by a frustoconical inner surface of the outer washer. 
     
     
         5 . The rig mat system of  claim 1 , wherein:
 the washer of each of the plurality of connector assemblies comprises a first washer; and   each connector assembly comprises a second washer having a central aperture defined at least partially by an frustoconical inner surface.   
     
     
         6 . The rig mat system of  claim 1 , wherein:
 the washer of each of the plurality of connector assemblies comprises a first washer; and   each connector assembly comprises a second washer comprising a split-ring formed from a pair of half-rings.   
     
     
         7 . The rig mat system of  claim 1 , wherein each connector assembly comprises an elastomeric plug configured to couple to a terminal end of the fastener. 
     
     
         8 . A rig mat, comprising:
 a support frame comprising a rectangular outer frame formed from a plurality of channels, and a plurality of rails extending through an interior of the outer frame, wherein an exterior surface of the outer frame is defined by a vertical surface and a pair of inclined surfaces extending from the vertical surface at non-zero angles from the vertical surface; and   a plurality of elongate billets coupled together and supported within the interior of the outer frame whereby loads applied to the plurality of billets are transferable from the plurality of billets to the support frame.   
     
     
         9 . The rig mat of  claim 8 , wherein the pair of inclined surfaces of the outer frame extend at acute angles from the vertical surface of the outer frame. 
     
     
         10 . The rig mat of  claim 8 , wherein each of the channels of the outer frame have a pair of lateral ends and an interior passage extending between the lateral ends of the channel. 
     
     
         11 . The rig mat of  claim 8 , wherein the plurality of rails of the support frame comprise one or more longitudinal rails extending parallel a central axis of the rig mat and one or more lateral rails extending orthogonal to the central axis of the rig mat. 
     
     
         12 . The rig mat of  claim 8 , wherein at least one of the rails has an I-shaped cross-section and includes a central web and a pair of flanges extending, in cross-section, orthogonal to the web. 
     
     
         13 . The rig mat of  claim 12 , wherein at least one of a pair of terminal ends of the web of the rail projects longitudinally from the pair of flanges of the rail. 
     
     
         14 . The rig mat of  claim 12 , wherein a longitudinal length of the web of at least one of the rails is greater than a longitudinal lengths of the pair of flanges of the rail. 
     
     
         15 . A rig mat system, comprising:
 a plurality of the rig mats of  claim 8 ; and   a link configured to releasably couple the plurality of the rig mats of  claim 8  together, the link comprising:
 a link frame comprising a base plate having a plurality of laterally extending arms; and 
   a plurality of connector assemblies releasably connectable to the plurality of arms of the link frame and to the plurality of the rig mats of  claim 8 .   
     
     
         16 . The rig mat system of  claim 15 , wherein the plurality of arms of the link underly the plurality of the rig mats of  claim 8  when the plurality of the rig mats of  claim 8  are coupled to the link. 
     
     
         17 . A rig mat, comprising:
 a support frame comprising a rectangular outer frame formed from a plurality of channels, and a plurality of rails extending through an interior of the outer frame, wherein at least one of the rails has an I-shaped cross-section and includes a central web and a pair of flanges extending, in cross-section, orthogonal to the web and wherein a longitudinal length of the web of at least one of the rails is greater than a longitudinal lengths of the flanges of the rail; and   a plurality of elongate billets coupled together and supported within the interior of the outer frame whereby loads applied to the plurality of billets are transferable from the plurality of billets to the support frame.   
     
     
         18 . The rig mat of  claim 17 , wherein at least one of a pair of terminal ends of the web of the rail projects longitudinally from the flanges of the rail. 
     
     
         19 . The rig mat of  claim 18 , wherein both of the pair of terminal ends of the web of the rail projects longitudinally from the flanges of the rail. 
     
     
         20 . A rig mat system, comprising:
 a plurality of the rig mats of  claim 17 ; and   a link configured to releasably couple the plurality of the rig mats of  claim 17  together, the link comprising:
 a link frame comprising a base plate having a plurality of laterally extending arms; and 
   a plurality of connector assemblies releasably connectable to the plurality of arms of the link frame and to the plurality of the rig mats of  claim 17 .   
     
     
         21 . The rig mat system of  claim 20 , wherein the plurality of arms of the link underly the plurality of the rig mats of  claim 17  when the plurality of the rig mats of  claim 17  are coupled to the link.