| 摘要 |
<p>The present invention relates to sucker rods and pony rods for use in a well. Conventional sucker or pony rods are formed from a single length of rod the ends of which are upset forged, machined, heat treated and cold rolled in order to provide a respective coupling at each end of the rod. The present invention provides many advantages compared with the conventional sucker rods by fabricating the sucker rod 10 from discrete components which are friction welded together. The sucker rod 10 is formed of an elongate central member 12 having a respective coupling component friction welded to each end thereof. The couplings may comprise a male component 14 and a female component 16. The coupling components 14, 16 are each provided with a shank 22, 34 which can be held in the chuck of a friction welding device. The shanks 22, 34 are shaped so as to enable raised lettering to be provided on the shank 22, 34 without the lettering 28 degrading the alignment of the component 14, 16 in the chuck. The central member 12 may be formed from a different material to the coupling components 14, 16. <IMAGE></p> |
