Hollow steel section

Because the interior of a hollow steel section (HSS) is difficult to inspect, some concern has been expressed regarding internal corrosion. In a sealed HSS, internal corrosion cannot progress beyond the point where the oxygen or chemical oxidation is consumed. If fine openings exist at connections, moisture and air can enter the HSS through capillary action or by aspiration due to the partial vacuum that is created if the HSS is cooled rapidly. 

Packer, J.A., Hraiderson, J.E., 1997. Hollow Structural Section Connections and Trusses A Design Guide, First edition 1992, second edition 1997. Canadian Institute of Steel Construction, Canada. 

The gauges are usually placed in turned-down sections of the shaft (which also increases sensitivity), and the connecting wires are best run along a keyway in the shaft or down the centre of a hollow shaft. If very small torques are to be measured, the gauges can be fitted to a special hollow plastic section of the shaft, which will deform more than a steel section, giving greater sensitivity. Gauges of this type are extremely delicate and must be handled and calibrated with extreme care. 

Two different modeling approaches can be used for the description of partial bond in SCC structural systems. The concentrated bond approach is based on the use of concentrated springs for the modeling of the connection. The springs are attached at the location of each connector, modeling either the action of the shear stud connectors between the steel and the concrete slab or the friction in concrete-filled hollow sections and partially encased steel sections. The second approach is based on the distributed bond model, which assumes a continuous bond stress and bond slip along the contact surface. For both approaches, the uplift is typically neglected therefore, it is considered that the concrete slab and the steel beam have the same vertical displacement and curvature. 

Figure 30.2 shows a diagram of the Fermi chopper. The shutter is a hollow steel cylinder, inside of which is a "sandwich" of alternate cadmium and aluminum sheets. The aluminum sheets, due to their small neutron cross section, are the "slits" that allow the neutrons to pass through when the slits are within l- -° of the horizontal position (parallel to the neutron beam). Due to the angular speed (cd) of the shutter, the slits are "open" for the time it takes the shutter to rotate 3 . 

The original auto bomb was a sheet metal box, 5 inches long, 3 1/2 inches wide, and 3 inches high. The walls of the box were hollow and filled with explosive, while the center section contained 350 steel pellets, about 1/4-inch in diameter, resting on a bed of powdered TNT. A pull fuze was attached to a weight. 

Figure 11. Electrodes in microcalorimetric vessels. A Schematic diagram of a section through a titration-perfusion microcalorimetric vessel equipped with a polarographic oxygen electrode and a pH electrode, a, sample compartment, volume 3 ml b, hollow stirrer shaft c, steel tube d, turbine stirrer e, O-rings f, combination pH electrode protected by a steel tube g, polarographic oxygen sensor (Clark electrode). B Record from a growth experiment with T-lymphoma cells. The vessel was completely filled with medium. Once the baseline had been established, the experiment was started (as indicated by the arrow) by the injection of 100 pi concentrated cell suspension.

Figure 25 Sketch of the Norsk Hydro magnesium cell [282], Lower figure shows a longitudinal section of the cell depicting the hollow cathodes. Upper figure shows the metal collecting chamber to the left (a) refractory material (b) graphite anode (c) steel cathode (d) refractory cover (e) metal outlet (f) metal (g) partition wall (h) electrolyte flow (i) electrolyte level (j) chlorine outlet.

In April 1982, before crops were planted, the drill rig was used to collect water samples from spots directly beneath the growing area of Field 5. A 30-cm metal well point with stainless-steel screen welded to the end of a section of hollow-stem auger was drilled to various depths below treated areas. Water samples were withdrawn through Teflon tubing inserted down the hollow stem into the point using the peristaltic pump. Sediment-free samples were bottled and stored for analysis as previously described. 

This decrease may not occur in the case of structures subjected to wetting/ drying cycles or in conditions where oxygen consumed at the surface of the passive steel is replaced. This may happen in hollow piles of offshore structures, as depicted in Figure 8.2. Similar conditions may arise in tuimels buried or submersed in chloride-containing environments. Rebars on the inside of hoUow (air-filled) structures may be effective cathodes with noble potentials. They increase the potential of rebars closer to the seawater side of the cross section, stimulating corrosion initiation at lower chloride contents than without additional cathodic effects. Subsequently they may increase the corrosion rate at the anodes by consuming the electrons produced. The final corrosion rate will be a function of the ratio between anodic and cathodic areas, which is influenced by the concrete resistivity. 

The multicylinder dryer section of a paper machine consists of a number (up to 70) of large, hollow, cast iron or steel cylinders over which the web passes. These cylinders are nsed to alternately heat the two sides of the sheet. The major mode of heat transfer is the conduction through the steam-heated cylinder shells. 

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