Tubing stainless steel

Inasmuch as the gas hydroly2es readily, all equipment should be purged repeatedly using inert dry gas before admitting boron trifluoride. Under anhydrous conditions, carbon steel equipment is satisfactory. Stainless steel and aluminum siUcon bron2e may also be used. Stainless steel tubing is recommended for both temporary and permanent connections. 

The food industry uses stainless steel tubing or piping extensively for moving food products conventional steel, cast iron, copper, plastic, glass (qv), aluminum, and other alloys are used for utilities. 

The vertical tube (water-cooled) generator consists of two concentric tubes the outer of which is cooled with water and acts as the ground electrode. Feed gas is introduced into the top of the inner stainless steel tube (which serves as the high voltage electrode), exits at the bottom of the outer tube, flows upward through the aimular space (which contains the electric discharge), and emerges at the top of the outer tube into a product gas manifold. 

Fig. 5. Plots of pump-down performance for pumps operating on 0.1-m-dia x 0.43-m-long stainless-steel tubing. Curves 1—4 are sputter-ion pumps of different makes curve 5 is Orbitron type and curve 6, LN-trapped oil DP. Pressure is measured using Bayard-Alpert gauge (BAG) (26). To convert Pa to...

The interior surface of the stainless steel tubing is usually poHshed to allow the particles to pack efficiently. An important consideration is uniformity of the... 

Half-inch copper tubing is commonly used for steam tracing. Three-eighths-inch tubing is also used, but the effective circuit length is then decreased from 150 feet to about 60 feet. In some corrosive environments, stainless steel tubing is used, and occasionally standard carbon steel pipe (one half inch to one inch) is used as the tracer. 

When austenitic stainless-steel tubes are used for corrosion resistance, a close fit between the tube and the tube hole is recommended in order to minimize work hardening and the resulting loss of corrosion resistance. 

Tubular Tubular membranes (Fig. 22-51) are supported by a pressure vessel, iisiiallv perForated or porous. It can be as simple as a wrapped nonw oven Fabric, or as robust as a stainless-steel tube. All rim with tube-side Feed. Thev are rnainlv used For UF, with some RO applications, particularly For Food and daiiw. The primary diameters available are 12 and 25 mm. Tubes are oFten connected in series parallel bundles, gasketed or potted, are also common. 

Attack at welds due to bacteria is possible, but it is not nearly so common as is often supposed. Because of residual stresses, microstruc-tural irregularities, compositional variation, and surface irregularities, welds show a predisposition to corrode preferentially by most corrosion mechanisms. Attack is common along incompletely closed weld seams such as at butt welds in light-gauge stainless steel tubing (Fig. 6.9A and B). Attack at carbon steel welds may occur. Figure 6.10 shows a severely corroded carbon steel pipe from a service water sys-... 

Flgure 6.8 Scalloped, partially undercut pits in a cross section of a 316 stainless steel tube. 

Figure 6.11 A Vie-in. (0.16-cm) diameter pit on the internal surface of a 316 stainless steel tube. Note the absence of significant corrosion products or deposits in the pit.

Sample Specifications 0.75 in. (1.9 cm) outer diameter, 304 stainless steel tubing... 

Sample Specifications /i6 in. (1.4 cm) outside diameter, 304 stainless steel tube... 

Figure 2.2.4 (Berty 1983) shows a tubular reactor that has a thermosiphon temperature control system. The reaction is conducted in the vertical stainless steel tube that can have various diameters, 1/2 in. being the preferred size. If used for fixed bed catalytic studies, it can be charged with a single string of catalytic particles just a bit smaller than the tube, e.g., 5/16 particles in a l/2 O.D. tube. With a smaller catalyst, a tube with an inside diameter of up to three to four particle diameters can be used. With such catalyst charges and a reasonably high Reynolds number— above 500, based on particle diameter—this reactor...

Estr-5(10)-ene-3a,17 -diol (10 g, 36.2 mmoles) is added over a period of 1 hr to a refluxing mixture consisting of 60 g (0.92 moles) of zinc-copper couple, 350 ml of dry ether and 180 g (54 ml, 0.67 moles) of methylene iodide. After the addition is complete, half of the solvent is removed by distillation and 200 ml dry ether is added. The reaction mixture is then transferred to a sealed stainless steel tube and maintained for 3 hr at 92° before being cooled in an ice bath and poured into 500 ml of saturated aqueous sodium bicarbonate solution. The resultant mixture is extracted with ether and the extracts are dried over anhydrous sodium sulfate and concentrated to yield a solid residue which gives 8.4 g (80%) 5,19-cyclo-5a,10a-androstane-3a,17) -diol mp 161-163° [aJo 40° (CHCI3), on crystallization from acetone. 

Many researchers choose to buy expensive GPC/SEC columns from one of the major producers because that producer s columns had been used in the past or because of a successful marketing campaign by one particular producer. It should be noted that repacked columns can be obtained for a fraction of the cost of new columns. American Polymer Standards repacked columns are guaranteed to perform just as well as new columns from any company. When a column is repacked the only parts reused are the stainless-steel tube and end caps. This hardware is then repacked using new frits and new ST-DVB gel. Each column is individually tested in a quality control laboratory and shipped in the customer s choice of solvent. American Polymer Standards offers a column repacking service because it is a practical, inexpensive way for customers to acquire state of the art GPC/SEC columns. 

From the pump outlet to the column inlet, the pressure is quite high. Stainless-steel tubing, fittings, and end pieces need to be used in this portion. 

The bare tracer is usually copper tubing, or sometimes carbon or stainless steel tubing, usually of -in., V2 -in., or... 

The first step in the production of synthesis gas is to treat natural gas to remove hydrogen sulfide. The purified gas is then mixed with steam and introduced to the first reactor (primary reformer). The reactor is constructed from vertical stainless steel tubes lined in a refractory furnace. The steam to natural gas ratio varies from 4-5 depending on natural gas composition (natural gas may contain ethane and heavier hydrocarbons) and the pressure used. 

Materials of construction are aluminium fins on stainless steel tube for ammonia, or aluminium or copper fins on aluminium or copper tube for the halocarbons. Aluminium tube is not yet common, but its use is expected to increase. 

The column. The columns most commonly used are made from precision-bore polished stainless steel tubing, typical dimensions being 10-30 cm long and 4 or 5 mm internal diameter. The stationary phase or packing is retained at each end by thin stainless steel frits with a mesh of 2 jum or less. 

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