Welds partial penetration

Alloy 201. A 3.2 mm (0.125 in.) thick alloy 201 sheet was welded in a butt joint configuration using a tool with a 16 mm (0.63 in.) diameter shoulder. The weld was a partial penetration weld, to avoid complications associated with getting the pin close to the backing plate. Yield and tensile strengths of the weld metal were 193 and448 MPa (28 and 65 ksi), respectively, compared with 103 and 406 MPa (15 and 60 ksi) for the base material. Elongation was 34% for the transverse specimen, compared to 50% for the base material. Very little tool wear was observed in this weld. 

AU nozzles must be integrally reinforced. Reinforcing pads, fillet welds and partial penetration welds are not allowed. Threaded connections must be of the straight ... 

Corner Joint A comer joint is a connection between two members at right angles to each other that is made with a fuU penetration weld, partial penetration weld or fillet welds. 

Crevice corrosion This type of corrosion occurs in situations where crevice forms, such as partial penetration welds and backing strips, are employed. 

Structural attachments may be made by complete penetration, partial penetration, or fillet welds. 

Partial penetration of the beam through the workpiece (as shown in Fig. 18.7) is common. Predictions and experimental results showing the relationship between electron beam welding machine settings and penetration depths (d ) have been reviewed [34]. This led to the development of a correlation to relate d and independent parameters involved in beam welding... 

Reference 24 reported on the welding of type 430 stainless steel using PCBN tools. The weld was performed at 550 rpm, with a travel speed of 80 mm/min (3.15 in./min). The weld was a partial penetration bead-on-plate weld. No mechanical property data were obtained. The weld appeared to be fully consolidated. Surface... 

Partial-Penetration Butt Weld. The partial penetration butt weld requires less force than a full-penetration butt weld in the same thickness. However, the intelligence or sensing requirements may be increased, due to increased sensitivity of the process. That is, the range of force over which quality welds can be produced may be smaller ttian for a full-penetration weld. 

Having partial-penetration butt welds, lap-penetration welding, or FSP applications. Many FSW tools can have a characteristic where, once the tool penetrates to a certain depth (e.g., shoulder below surface of material), it takes less and less force to plunge the tool. Thus, there is an unstable mode in the FSW process where the tool can potentially dig into the material, if operating in a force-controlled manner. In these cases, position or a combination of force and position control may be more desirable. 

As mentioned previously, penetration is usually expressed by the ratios of the (depth/width) (DAV) and the (back/front) widths (Wb/Wf) for partial- and full-penetration welds, respectively the latter parameter is subject to welding characteristics and is a less satisfactory measure than (DAV). 

Fillet welds partial-penetration groove welds joining component elements of built-up members such as flange-to-web connections may be designed without regard to the tensile or compressive stress in these elements parallel to the axis of the welds. 

Examination of weld samples taken in 1977 showed some partially penetrating sodium-side cracking. The significance of this was not understood at the time. The discovery, however, prompted a major programme to develop non-destructive methods of detecting partially-penetrating cracks. 

A model of particular importance for the present analysis is concerned with the heatup and possible melting of the upper in-vessd structures (upper shroud head, standpipes, steam separators, and steam dryers). The shroud-head/steam-separator assembly consists of a domed base on top of whidi is welded an array of standpipes with a multi-stage steam separator located on the top of each standpipe. The entire assembly, made of stainless steel, rests on the top-guide grid and forms a cover for the core outlet plenum region. The steam dryer assanbly is mounted in the reactor vessel above the shroud-head/steam-separator assembly. Since, in tihe case of an accident, the upper shroud head may be directiy exposed to a high-temperature core, the combined effects of radiation from the core and convective/radiative heat transfer from the hot steam/gas mixture in the upper plenum, may increase the shroud temperature to failure point. When the weakened shroud head cannot support the mass above it, the upper structures may coUapse onto the core (except for the steam dryer which has a separate support system). The molten steel from these structures may penetrate the hot and partially molten core and flow into the lower plenum and, following lower head failure, into the containment. 

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