piece the first pipe jack clamp 110 is already secured to the first pipe jack 120 while conventional clamps have to be held in place when screwing them down which can slip causing injury or damage now referring to fig3 which is a front view of a second pipe jack clamp 210 exhibiting a second work piece 124 held in position between a second head 218 and a second pipe jack 220 this is because the second pipe jack clamp 210 is designed to secure a work piece having a shorter maximum diameter the maximum diameter work piece the second pipe jack clamp 210 can secure is approximately 11 2 inches the second pipe jack clamp 210 comprises a second yoke 212 which comprises a second yoke cross member 212a the second yoke 212 further comprises a second yoke boss 212b secured to an upper side middle of the second yoke cross member 212a the second yoke boss 212b and the second yoke cross member 212a comprise a threaded opening therethrough the second yoke 212 further comprises a pair of second yoke side members 212c are each securely attached at opposite distal ends of the second yoke boss 212b extending at an obtuse outward angle downwardly therefrom the second yoke 212 further comprises a pair of second yoke lower side members 212d are each securely attached at a distal end of each of the second yoke side members 212c extending at a right inward angle downwardly therefrom the second pipe jack clamp 210 further comprises a second threaded stem 214 is engageably mounted within the threaded opening the second threaded stem 214 further comprises a second handle 216 securely attached at an upper distal end thereto a second head 218 is rotatably mounted on a bottom distal end of.