Fillet Weld Size

Due to limitation in the height at the reinforcement zone, no practical fillet weld size will supply enough reinforcement area therefore, the connection must be... 

F = total load of bed, lb F, = allowable bending stress, psi Fy = minimum specified yield strength, psi W( = fillet weld size, in. h = height of beam seat or length of clip, in. 

V = shear load, lb w = required fillet weld size, in. a = thermal coefficient of expansion, in./in./°F = flat plate coefficients... 

T = tail end load, lb Tb = bolt pretension load, lbs T, = tangential force, lb wi = fillet weld size, shell to re-pad W2 = fillet weld size, re-pad to shell W3 = fillet weld size, pad eye to lug VV4 = fillet weld size, base plate to skirt W5 = uniform load on vessel, IbAn. 

Make fillet weld size no greater than. 75 t. ... 

Fu = Minimum specified tensile strength, PSI Fw = Allowable shear stress, PSI fb = Bending stress, PSI fw = Fillet weld size... 

NOTE When the angle between members exceeds 105 deg, size is of less significance than effective throat (see also throat of a fillet weld). 

Fillet welds (including socket welds) may vary from convex to concave. The size of a fillet weld is determined as shown in Fig. GR-3.4.7(a). 

The size of an equal leg fillet weld is the leg length of the largest inscribed isosceles right triangle (theoretical throat = 0.707 X size). 

An NPS 8 run (header) in a piping system has an NPS 4 branch at right angles (see Fig. E-l). Both pipes are Schedule 40 API 5L Grade A seamless. The design conditions are 300 psig at 400°F. The fillet welds at the crotch are minimum size in accordance with para. IP-3.4. A corrosion allowance of 0.10 in. is specified. Is additional reinforcement necessary ... 

This total reinforcement area is greater than the required area therefore, a reinforcing ring 6 4 in. O.D., cut from a piece of NPS 8 Schedule 40 API 5L Grade A seamless pipe and welded to the connection with minimum size fillet welds would provide adequate reinforcement for this connection. 

Make fillet weld leg size no greater than 0.75tw. 

The strength of a fillet weld is usually given as strength per linear inch of weld for a certain size of fillet. Because fillet welds are not often the full thickness of a plate, the size of a fillet is less than the thickness of a plate. The American Welding Society publishes weld strength data. 

Arrow and Other Side welds are of the same size unless otherwise shown. Dimensions of fillet welds must be shown on both the Arrow Side and the Other Side Symbol. 

Kxample 11.12. An K in. NPS Schedule KO branch (nozzle) is attached at right angle to u 20-in. NFS Schedule 40 run (header) with a full penetration weld with fillet weld cover. The allowable stress is 13.1 ksi. Design pressure is 600 psi at a design temperature of 900 F. Determine the reinforcing requirements and pad size, if required. 

With max. avg. < c below their respective allowable stresses, and the 6mm fillet welds an each side of the plate are satisfactory The plate should be 2mm (1/16") greater than the weld size, so an 8mm thick plate should suffice. With a corrosion rate of 3 mm, the actual clip plate thickness is 11 mm Note The total load is transmitted through the fillet welds only, and no credit is given for possible bearing between the lower part of the clip and the vessel wall. The assumption that the shear, fa,g, is carried uniformly in the welds is ubiquitously accepted. 

Washers for the oversized holes should be fabricated from ASTM A36/A36M steel plate. They may be round, square, or rectangular, and generally have holes that are 1/16-in. (1.6 mm) larger than the anchor. The thickness must be suitable for the forces to be transferred. Minimum washer sizes and thicknesses are shown in the table. (AISC Manual, 13 Edition, Part 14 and Table 14-2). Washers which will be welded to the base plate in order to transmit shear must be thickened to avoid overstressing in bearing and to be sufficiently thick for fillet welding. 

Lap joints should have an overlap of at least 5 X i inches, and in no case should the overlap he le than 1 in. Vertiail lap joints should have continuous full-filk. t welds both inside arnl out. On horizontal lap joints, as shown in Fig. 3-U, the fillet should have a size not less than one third the thickness of the Ihinner plate, and in no case should it l>e less,"than Jtr," in ... 

Corner Welds No beveling is required, vreld outside. Size of fillet is not to be specified—fillet a tittle heavier than plate is understood. For heavy strains v td one bead ir de in addition to outside weld. See folowing examples ... 

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