Upset threads

Figure 2.1 Anchor Rod with Upset Threads 2.2.S.4 Shot Peening...

Design for anchor ductility requires that the necessary conditions for elongation over a reasonable gage length are fulfilled that is, that strain localization will not limit the yield strain. This may involve the use of upset threads (see 2.2.5.3) or other detailing methods to avoid strain localization. Furthermore, if it is desired that yielding of the anchor provide the required ductility in the connection, the reinforcement should be proportioned to develop the strength of the anchor as follows ... 

Anchors with upset threads (see 2.2.5.3) provide the advantage of assuring that yielding will occur outside of the threaded portion of the anchor. Upset threads however, are not necessary for anchors resisting seismic loads. 

Size Outside Diameter, in. OD Nominal Weig ht Upset and Threaded lb per ft Wall Thickness, in. WALL Inside Dia., in. ID Plain End. Ib/fl Calculated Weight Up-set and Threads Sid. Opt. lb lb ... 

The minunum outside diameter of upset, Z>, is limited by the minimuni length of full-crest threads. See API Std. SB. 

Fatigue that often causes failure at the last engaged thread. There is no positive remedy, but using external upset tubing in place of nonupset tubing greatly delays the start of this trouble. 

In many traditional cultures, illness is believed to be caused by psychological conflicts or disturbed social relationships that upset an equihbrium which is expressed in the form of physical or mental problems (33). Although Africa has a diverse culture, there is a common thread that follows that the disraption of this equilibrium, what we call illness, may be caused by external psychological or spiritual factors, or both, that relate to African cosmology and "threaten the intactness of the person" 34). In traditional cultures, then, healing involves restoring this equilibrium. 

A third type, known as a Philidas self-locking nut, Fig. 12.8(e), has a reduced diameter above the hexagon. Two slots are cut opposite each other in the reduced diameter and the metal above the slots is pushed down, which upsets the thread pitch. When screwed in position, the thread is gripped hy the upset portion, preventing the nut from working loose. 

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