Fittings butt-welding

Plain-end pipe used for socket-weld joints (Fig. 10-126) is available in all sizes, but fittings and valves with socket-weld ends are limited to sizes 3 in and smaller, for which the extra cost of the socket is outweighed by much easier alignment and less skill needed in welding. The joint is not so resistant to bending stress as the butt-welded joint but is otherwise equal, except that for some fluids the crevice between the pipe and the socket may promote corrosion. ANSI B16.il—1973,... 

Components without Specific Ratings Components such as pipe and butt-welding fittings are gener y furnished in nominal... 

Designers are cautioned that cast butt-welded fittings may have considerably heavier walls than that of the pipe with which they are used. Large errors may be introduced unless the effect of these greater thicknesses is considered. 

Figure 2-8. Light weight stainless steel butt-weld fittings/tubing for low pressure applications. By permission, Tri-Clover, Inc.

Figure 2-21. Equivaient iength of fittings for pipe systems. Note preferred use for 1 / in. and larger pipe butt-welded or socket-welded connections (this author). By permission. Tube Turns Div., Chemitron Corp. Bull. TT 725,1952, reference now to Tube Turns Technologies, Inc.

Wrought Stainless Steel Butt-Welding Fittings... 

Steel butt welding fittings shall comply with either ASME B16.9 or MSS SP-75 and shall have pressure... 

Branch Connections Branch connections may be made with manufactured tees, fabricated reinforced and nonreinforced branch connections (Fig. 10-130), or manufactured integrally reinforced branch connections. Butt-welded fittings offer the best opportunity... 

V-Clamp Joints These joints (Fig. 10-143) are attached to the pipe by butt-weld or expanded joints. Theoretically, there is only one relative position of the parts in which the conical surfaces of the clamp are completely in contact with the conical surfaces of the stub ends. In actual practice, there is considerable flexing of the stub ends and the clamp also complete contact is not required. This permits use of elastomeric gaskets as well as metal gaskets. Fittings are also available with integral conical shouldered ends. 

Components without Specific Ratings Components such as pipe and butt-welding fittings are generally furnished in nominal thicknesses. Fittings are rated for the same allowable pressures as pipe of the same nominal thickness and, along with pipe, are rated by the rules for pressure design and other provisions of the code. 

Butt-welded joint, reducer, or weld-neck flange Double-welded slip-on flange Fillet welded joint, or socket weld flange or fitting Lap joint flange (with ASME B 16.9 lap joint stub)... 

ASME B16.9 Factory-made wrought butt-welding fittings... 

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