Stud tensioners

Either stud tensioners or torque wrenches are used for prestressing bolts to the required stress for... 

In this case, the nut is not there to create the stud tension, but only used to secure the elongation of the stud. Sleeve nuts achieve this goal with a minimum of metal. Sleeved nuts may have holes drilled in them to facilitate the turning of the nut during stud elongation. 

Figure 8-27. Piping sub-assy showing, tapered studs, lens ring gasket and clearances for stud tensioning equipment.

The design of the steam generator tubes permits full-length inspection of the tubes from the point of entry on the hot leg side to the tube end on the cold leg side, and vice versa. To make personnel and equipment access for in-service inspection easier and quicker, the diameter of the two primary head manways has been increased to 21 inches from the 16-inch diameter of the System 80 steam generator primary head manways (see CESSAR-DC Section 5.4.2). The design permits expeditious removal and attachment of the manway covers using multiple stud tensioning equipment. 

Provides support for the vessel head stud tensioner-detensioner during refuelling. 

In addition, stud bolts should not be indiscriminately mixed with ordinary bolts or used in their place. They are often made of different grades of steel and produce a different tension. 

Figure 2 3.5 KW electron beam furnace components (a) Water-cooled furnace block (b) Copper hearth (c) Cooling pipes (d) Top plate of furnace (earth potential) (e) Filament (f) Focus lid (g) Lid (h) High-tension supply (i) Low-tension supply (j) Ceramic insulators (k) Cooling pipes for top plate (1) locating stud for hearth adjustment and (m) Water conduit.

Sa Main Studs Ambient ASME Code Allowable Stress, Tension ... 

We are all aware of the compound effect that bending will have when combined with tension. However, in the design of the bolting, perfect alignment and pure tension are assumed. Our designs are based on the stud being stressed perfectly in tension without any bending. Without spherical washers, this may not be the case. 

Spherical washers are used in pairs and carefully machined to nest together. In this manner, whatever misalignment occurs, the spherical washers automatically account for the misalignment and keep the stud in pure tension. 

As a free-running nut is tightened down, there is a progressive increase in the torque required and in the tension in the stud or bolt. But, because of the inelastic collapse of the load-bearing peaks of the engaged surfaces, the removal torque for the fastener will normally be some 90 per cent of that required to tighten it. This residue of the pre-load is lost within some 60° of rotation during removal (see... 

In some critical assemblies, such as the fitting of an internal combustion engine cylinder head, correct clamping load is vital. Either the traditional torque/tension method, or the more recently developed techniques of differential torque analysis must therefore be used. With torque/tension, the relationship must not be modified by the anaerobic materials used to lock the stud and nut. It has been shown that the relationship remains effectively unaltered if the fasteners are not degreased before assembly. For maximum precision, cleaned fasteners may be used in conjunction with special lubricating anaerobic versions. 

MULTIPLE CONTACT LINKAGE. Below the universal joint in the vacuum space, force on the tensile specimen is transmitted through a stack of 1/2 mil stainless steel washers (F). A central stud connected to the universal joint supports the stack from below and a retaining well which is welded into the outer can restrains the top of the stack. Thus the stack is placed in compression as tension is applied to a specimen within the can, and the heat conducted through Throughout this paper, the letters in parentheses refer to similarly designated parts in Fig. 1,... 

The pull-off method has been standardized internationally. This test utilizes stress patterns caused by loads acting either normal or parallel to the plane of contact. A stud, normally made of steel, is glued with the coating and is subjected to axial tension until separation of the paint film occurs. This determines the maximum tensile stress that is possible at the interface. 

Steel embedded plates are often used to transfer loads from structural members to concrete structures or foundations. Such plates are often cast-in-place for constructability and to provide a smooth surface for attachment. These plates are attached to the concrete with welded anchors, which typically consist of headed studs, headed anchors, weldable rebar, or shear lugs they can be designed to resist applied tension, shear, and moment. Welding should be compatible with the anchor type. 

There are several examples of single and multiple studs welded to embedded plates under tension, shear, moment, and combinations of these loads in ACI 349.2R. Engineers are encouraged to use this reference when the need arises. 

Steel Under Earthquake Excitations Reinforcing steel in external reinforced crmcrete jackets for the retrofit and strengthening of existing reinforced concrete or steel members comes mainly in the form of bars. Usually, the stress-strain behavior under tension-compression is cmcial to assess the longitudinal bars contribution. The stress-strain behavior under tension is of interest for the transverse reinforcement (stirmps). Steel dowels and stud shear connectors may involve shear (or tensile) behavior of steel- or bond-related issues. External steel plates may be considered under multiaxial loading (i.e., in cases of shear strengthening in order to estimate their yield stress). Bond-related issues may concern bar-concrete interfaces, bar-resin-concrete interfaces (NSM applications), or plate-resin-concrete interfaces under cyclic loading. 

Adhesion test, stud-pull An adhesion test whereby a protrusion (stud) is bonded to the surface of the film and pulled in tension. 

One of the simplest and most useful tests performed on reflow-attached flip chips to determine the adequacy of the solder joints (i.e., C4) is a tensile pull test (Fig. 31). This is done by adhesively attaching a metal stud to the back of a joined chip and pulling the joints in tension at a slow strain rate (approximately 1.0x10 sec ). The pull force is measured during the test using an appropriate load cell. The pull strength is a useful parameter, but the failure mode is a very important indicator of joint quahty. Planar failure at the solder joint interfaces is indicative of a weak and unacceptable interface condition. 

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