Clamp for circular objects

Abstract

A clamp includes first and second parts, each of the parts having a circular central section and a pair of straight extensions extending away from the circular central section in opposite directions. In the first part the holes are closed holes, while in the second part the holes are open holes, connected by slots to an upper edge of the part. Bolts may be pre-located through the closed holes, with nuts threaded onto the bolts, but not tightened. The pre-placed bolts may be received through the slots and into the open holes of the second part. The nuts may then be tightened against the second part to clamp the circular central sections on opposite sides of a circular object, such as a vertical pipe run, between the parts. According to a variant, the bolts are permanently secured to the first part so as to prevent rotation of the bolts.

1 . A clamp comprising: 
 a first bar portion having a first curved central section, and a pair of first extensions extending from opposite ends of the first curved central section;    a second bar portion having a second curved central section, and a pair of second extensions extending from opposite ends of the first curved central section; and    a pair of fasteners joining the bar portions together;    wherein the first bar portion has a pair of holes in respective of the first extensions;    wherein the second bar portion has a pair of holes in respective of the second extensions; and    wherein at least one of the holes in the second extensions is an open hole.    
   
   
       2 . The clamp of  claim 1 , wherein the holes in the first section are closed holes.  
   
   
       3 . The clamp of  claim 1 , wherein both of the holes in the second extensions are open holes.  
   
   
       4 . The clamp of  claim 3 , wherein in a pair of slots in respective of the second extensions allow shafts of the fasteners to enter the open holes through the slots.  
   
   
       5 . The clamp of  claim 4 , wherein at least one of the slots is a straight slot substantially perpendicular to an edge of one of the second extensions.  
   
   
       6 . The clamp of  claim 4 , wherein at least one of the slots is an L-shape slot.  
   
   
       7 . The clamp of  claim 4 , wherein at least one of the slots is a diagonal slot, angled to an edge of one of the second extensions.  
   
   
       8 . The clamp of  claim 4 , wherein the slots have the same shape.  
   
   
       9 . The clamp of  claim 4 , wherein the slots have different shapes.  
   
   
       10 . The clamp of  claim 1 , wherein at least one of the fasteners is attached to the first portion.  
   
   
       11 . The clamp of  claim 1 , wherein the at least one of the fasteners is attached to the first portion by ring staking.  
   
   
       12 . The clamp of  claim 1 , wherein the fasteners are bolts.  
   
   
       13 . A method of installing a riser clamp around an object to be clamped, the method comprising: 
 placing respective central curved sections of first and second bar portions on opposite sides of the object to be clamped, wherein the curved sections of the bar portions are between respective pairs of extensions connected to opposite sides of the curved section; and    coupling the bar portions together, with the object to be clamped between the central curved sections, wherein the coupling includes passing a shaft of a fastener that is coupled to one of the extensions of the first bar portion, through a slot and into an open hole in one of the extensions in the second bar portion.    
   
   
       14 . The method of  claim 13 , wherein the fastener is precoupled to the first bar portion, before the placing.  
   
   
       15 . The method of  claim 14 , wherein the fastener is attached to the first bar portion.  
   
   
       16 . The method of  claim 13 , wherein the fastener is a bolt, and wherein the coupling further includes tightening a nut threadedly engaged on a threaded bolt shaft of the bolt.  
   
   
       17 . The method of  claim 13 , wherein the coupling includes passing respective shafts of a pair of fasteners that are coupled to respective extension of the first bar portions, through respective slots and into respective open holes in respective extensions in the second bar portion.  
   
   
       18 . A clamp bar portion comprising: 
 a central curved section;    a pair of extensions connected to opposite ends of the central curved section; and    a pair of bolts passing through holes in respective of the extensions;    wherein the bolts are fixedly attached to the extensions.    
   
   
       19 . The bar portion of  claim 18 , wherein the bolts are ring staked to the extensions.  
   
   
       20 . The bar portion of  claim 18 , wherein the holes are internally threaded holes.  
   
   
       21 . A clamp comprising: 
 a first bar portion having a first curved central section, and a pair of first extensions extending from opposite ends of the first curved central section;    a second bar portion having a second curved central section, and a pair of second extensions extending from opposite ends of the first curved central section; and    a pair of bolts joining the bar portions together;    wherein the first bar portion has a pair of holes in respective of the first extensions;    wherein the second bar portion has a pair of holes in respective of the second extensions; and    wherein at least one of the holes in the second extensions includes means for receiving a bolt shaft of one of the bolts while the bolt shaft is between a bolt head and a nut threaded on the bolt shaft.    
   
   
       22 . The clamp of  claim 21 , wherein the both of the holes in the second extensions include the means for receiving.  
   
   
       23 . The clamp of  claim 22 , wherein the means for receiving include the holes being open holes.  
   
   
       24 . The clamp of  claim 22 , 
 wherein the means for receiving include the holes being closed slots each having a larger-diameter portion in communication with a smaller diameter portion; and    wherein the larger-diameter portion allows passage of the nut therethrough, but the smaller-diameter portion does not allow passage of the nut therethrough.    
   
   
       25 . The clamp of  claim 24 , wherein the slots have a keyhole shape.  
   
   
       26 . The clamp of  claim 25 , wherein the slots are oriented along lengths of the second extensions.  
   
   
       27 . The clamp of  claim 25 , wherein the slots are oriented along widths of the second extensions.