Cold formed sections

The steam dryer is a stainless steel assembly mounted in the reactor vessel above the steam separator which forms the upper boundary of the wet steam plenum. Vertical guides on the inside of the vessel align the dryer during installation. The steam dryer ring supports the dryer on the dryer support brackets. In many BWR plants, the steam dryer support ring is a cold-formed section made of stainless steel. In other plants, the stainless steel steam dryer support ring was installed in a non-cold-worked condition. 

A key consideration in the design of cold formed members for blast is premature buckling of the relatively thin webs. This response limits the ultimate resistance which can be obtained by reducing the load capacity due to a change in the cross section. A factor of 0.9 is recommended to be applied to the design resistance to... 

For structural and cold formed steel, the Load and Resistance Factor Design (LRFD) method is used. The Strength Design Method is used for reinforced concrete and masonry materials. Details on the Implementation of these methods arc given in subsequent sections in this chapter for each class of material. 

The enhancement of these types of buildings is achieved by using closer spacing for the building frames and girts and combining sections of the standard AISI cold formed shapes to achieve symmetry. 

Table 3.1-13tr Strengthening of Ag (99.975%) by cold forming as a function of reduction in cross section in % [1.217, p.204]...

Cold forming means the process of using press brakes, rolls, or other methods to shape steel into desired cross sections at room temperature. 

B) The material being handled by the articulating/knuckle-boom crane is a prefabricated component. Such prefabricated components include, but are not limited to Precast concrete members or panels, roof trusses (wooden, cold-formed metal, steel, or other material), prefabricated building sections such as, but not limited to Floor panels, wall panels, roof panels, roof structures, or similar items ... 

The core shroud separates the upward flow of coolant through the reactor core from the downward recirculation flow. The core shroud is an assembly of cylinders fabricated from rolled and welded stainless steel plate material, which encompasses the reactor core as shown in Figure 2-15. For the replaced core shrouds of Japanese BWRs and the ABWR core shrouds, a forged ring material is used to decrease the weld lines. Typical core shroud weld locations are shown in Figure 2-15. Shell sections are normally solution heat treated, cold formed and joined with longitudinal and circumferential welds. The steam separator/shroud... 

Cold Forming. Titanium and titanium alloys are commonly stretch formed without being heated, although the die is sometimes warmed to 150 °C (300 °F). Simple brake forming of straight sections also can be done at room temperatvire if adequate bend radii are designed into the tool. When formed at room temperature, commercially pure titanium and titanium alloys behave like cold-rolled stainless steel. Shapes that can be successfully press formed in V -hard stainless steel usually can be press formed in commercially pure titanium, althou titanium may require hot sizing to produce severe contours. 

All forming, bending, stamping, and deep drawing operations are normally performed cold. Heavy sections can be heated for forging to approximately 425°C. 

Maximum section ranging 0.25-22 mm, depending on material for impact extrusion. No limit for cold forming. 

Conduct the preparation in the fume cupboard. Dissolve 250 g. of redistilled chloroacetic acid (Section 111,125) in 350 ml. of water contained in a 2 -5 litre round-bottomed flask. Warm the solution to about 50°, neutralise it by the cautious addition of 145 g. of anhydrous sodium carbonate in small portions cool the resulting solution to the laboratory temperature. Dissolve 150 g. of sodium cyanide powder (97-98 per cent. NaCN) in 375 ml. of water at 50-55°, cool to room temperature and add it to the sodium chloroacetate solution mix the solutions rapidly and cool in running water to prevent an appreciable rise in temperature. When all the sodium cyanide solution has been introduced, allow the temperature to rise when it reaches 95°, add 100 ml. of ice water and repeat the addition, if necessary, until the temperature no longer rises (1). Heat the solution on a water bath for an hour in order to complete the reaction. Cool the solution again to room temperature and slowly dis solve 120 g. of solid sodium hydroxide in it. Heat the solution on a water bath for 4 hours. Evolution of ammonia commences at 60-70° and becomes more vigorous as the temperature rises (2). Slowly add a solution of 300 g. of anhydrous calcium chloride in 900 ml. of water at 40° to the hot sodium malonate solution mix the solutions well after each addition. Allow the mixture to stand for 24 hours in order to convert the initial cheese-Uke precipitate of calcium malonate into a coarsely crystalline form. Decant the supernatant solution and wash the solid by decantation four times with 250 ml. portions of cold water. Filter at the pump. 

In a 500 ml. wide-mouthed reagent bottle place a cold solution of 25 g. of sodium hydroxide in 250 ml. of water and 200 ml. of alcohol (1) equip the bottle with a mechanical stirrer and surround it with a bath of water. Maintain the temperature of the solution at 20-25°, stir vigorously and add one-half of a previously prepared mixture of 26-5 g. (25 -5 ml.) of purebenzaldehyde (Section IV,115) and 7 -3 g. (9-3 ml.) of A.R. acetone. A flocculent precipitate forms in 2-3 minutes. After 15 minutes add the remainder of the benzaldehyde - acetone mixture. Continue the stirring for a further 30 minutes. Filter at the pump and wash with cold water to eliminate the alkali as completely as possible. Dry the solid at room temperature upon filter paper to constant weight 27 g. of crude dibenzalacetone, m.p. 105-107°, are obtained. Recrystallise from hot ethyl acetate (2-5 ml. per gram) or from hot rectified spirit. The recovery of pure dibenzalacetone, m.p. 112°, is about 80 per cent. 

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