摘要:
The joining element comprising a fastener or screw shank having a head has adjacent to said head a portion with a plurality of parallel, concentric fit-stretch rings, whose external diameter is 0.1 to 0.5 mm larger than the external diameter of the fastening thread. A fit slot is formed between in each case two rings, with a notch groove radius which is two to three times the top radius of the fastening thread. In the transition region between the head and the aforementioned portion is provided a fillet with a rounded portion having a diameter corresponding roughly to the pitch diameter of the rings and with a radius of curvature amounting to approximately to 0.1 to 0.15 times the external diameter. The rings have a stressing cross-section in the notch groove corresponding to the stressing cross-section of the fastening thread. The top width of the rings approximately corresponds to the side width of the preliminary shape of the rings.
摘要:
A swivel connector for connecting a first and second line for towing of one line by the other wherein there is provided an upper limit on loading that may be imposed between the lines as a safeguard to damage to one of the lines. The swivel connector includes first and second swivel heads connected by a load pin. The load pin is fixed to fracture at an approximate predetermined loading between the first and second swivel heads which loading is beneath that which would otherwise cause danger or damage to one of the lines. Upon fracture of the pin, it is readily replaced so that the swivel head can be used again.
摘要:
A self-straining bolt comprises a hollow shank having a flanged and screw-threaded head at one end, a core member, a rod within the shank and secured to the other end of the shank a nut in screw-threaded engagement with the core bears against the shank at the said one end. The bolt is tensioned by means of a tensioning head comprising two coaxial jacking means, one for tensioning the hollow shank by bearing on the core member and the other for tensioning the core member by bearing on the shank head.
摘要:
A method for manufacturing bolts of a given grade and size in which, after forming, threading and heat treating, each bolt is work hardened by the application and subsequent removal of a tensile force of magnitude somewhat above the minimum proof load for the given grade and size of bolt, so that all bolts so treated will have the same yield point and the torque rotation curve for each bolt will have a discontinuity in slope at this common yield point.