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ASME 1331.3-2016 <br /> Fig. 328.4.4 Preparation for Branch Connections <br /> I <br /> m >_0 mm On.).) <br /> g O^� i � I <br /> I <br /> m� 9 <br /> � I <br /> (a) Ib► I (c) <br /> g = root gap per welding specification <br /> m=the lesser of 3.2 mm(t/g in.)or 0.5 Tb <br /> (c) Branch Connection Welds (d) Peening is prohibited on the root pass and final <br /> (1) Branch connections that abut the outside surface pass of a weld. <br /> of the run pipe shall be contoured for groove welds that (e) No welding shall be done if there is impingement <br /> meet the WPS requirements [see Fig. 328.4.4, on the weld area of rain,snow,sleet,or excessive wind, <br /> illustrations (a) and (b)]. or if the weld area is frosted or wet. <br /> (2) Branch connections that are inserted through a (f) Welding End Valves. The welding sequence and <br /> run opening shall be inserted at least as far as the inside procedure and any heat treatment for a welding end <br /> surface of the run pipe at all points [see Fig. 328.4.4, valve shall be such as to preserve the seat tightness of <br /> illustration (c)] and shall otherwise conform to the valve. <br /> para. 328.4.3(c)(1). <br /> 328.5.2 Fillet and Socket Welds. Fillet welds <br /> (3) Run openings for branch connections shall not <br /> deviate from the required contour more than the dimen- <br /> sion m in Fig. 328.4.4. In no case shall deviations of the cave. The size of a fillet weld is determined as shown <br /> shape of the opening cause the root spacing tolerance in Fig. 328.5.2A. <br /> limits in the WPS to be exceeded. Weld metal may be (a) Typical weld details for slip-on and socket welding <br /> added and refinished if necessary for compliance. flanges are shown in Fig. 328.5.2B; minimum welding <br /> (d) Spacing. The root opening of the joint shall be dimensions for other socket welding components are <br /> within the tolerance limits in the WPS. shown in Fig. 328.5.2C or MSS SP-119. <br /> (b) If slip-on flanges are single welded,the weld shall <br /> 328.5 Welding Requirements be at the hub. <br /> 328.5.1 General 328.5.3 Seal Welds. Seal welding shall be done by <br /> (a) Welds,including addition of weld metal for align- a qualified welder. Seal welds shall cover all exposed <br /> ment [paras. 328.4.2(b)(4) and 328.4.3(c)(3)], shall be threads. <br /> made in accordance with a qualified procedure and by <br /> qualified welders or welding operators. 328.5.4 Welded Branch Connections <br /> (b) Each qualified welder and welding operator shall (a) Figures 328.5.4A through 328.5.4F show accept- <br /> be assigned an identification symbol. Unless otherwise able details of branch connections with and without <br /> specified in the engineering design, each pressure- added reinforcement, in which the branch pipe is con- <br /> containing weld or adjacent area shall be marked with nected directly to the run pipe. The illustrations are <br /> the identification symbol of the welder or welding oper- typical and are not intended to exclude acceptable types <br /> ator. In lieu of marking the weld, appropriate records of construction not shown. <br /> shall be filed. (b) Figure 328.5.4D shows basic types of weld attach- <br /> (c) Tack welds at the root of the joint shall be made ments used in the fabrication of branch connections.The <br /> with filler metal equivalent to that used in the root pass. location and minimum size of attachment welds shall <br /> Tack welds shall be made by a qualified welder or weld- conform to the requirements herein. Welds shall be cal- <br /> ing operator. Tack welds shall be fused with the root culated in accordance with para.304.3.3 but shall be not <br /> pass weld, except that those that have cracked shall be less than the sizes shown in Fig.328.5.4D.Figure 328.5.4F <br /> removed. Bridge tacks (above the weld) shall be shows the basic types of attachment welds used with <br /> removed. integrally reinforced branch connection fittings. The <br />