270 positioned on the stationary case member 210 and at the other end by a second upper mounting support 274 positioned on the moving arm case member 240 the lower grip actuator 262 is rotatably mounted horizontally across the case assembly 200 at one end by a lower mounting support 272 positioned on the underside of the stationary case member 210 and at the other end by a second lower mounting support 276 positioned on the underside of the moving aim case member 240 the grip actuators 260 262 are mounted to the mounting supports 270 272 274 276 by retaining bolt and lock nut assemblies extending through the ends of the actuators these retaining bolts also extend through idler rollers 278 positioned between the mounting supports 270 272 274 276 as will be described in more detail below the upper and lower grip actuators 260 262 are generally maintained in an open or fully extended position to receive the pipe 602 within the case assembly 200 once the pipe 602 is positioned within the case assembly 200 the grip actuators 260 262 are activated to move the moving arm case member 240 towards the stationary case member 210 to grip the pipe 602 the idler rollers 278 correspond with and are disposed between corresponding drill holes 228 in the moving arm and stationary case members 240 210 the idler rollers 278 are free to rotate relative to the moving arm and stationary case members 240 210 and are maintained in spaced apart relation from the sidewalls 212 242 to form a passage for passing the chain 302 therethrough the idler rollers 278 are.