Stainless Steel Applications

This innovative closed loop process received the Pennsylvania s Governor s Waste Minimization Award in 1987, presented to Washington Steel by the Pennsylvania Department of Environmental Resources. 

AQUATECH Commercial Process For the Recovery of Spent Pickle Acid 

WASHINGTON STEEL OPERATIONS 10/17-4/17 PROCESSED waste acid vs p couct acid 

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Soil Fat and protein Surface Stainless steel Application Method Clean in place Manufacture Ribbon or paddle blender... 

Soil-Oil, fat, protein Surface-Stainless steel Application Method-Cleaning in place Manufacture-Dry blend/Agglomerat i on... 

A new concept creep-fatigue failure criterion was proposed using secondary creep basis ductility exhaustion for stainless steels. Applicability of the present criterion to modified 9Cr-lMo steel was validated by the mechanical and metallurgical studies. The equations of cyclic plasticity of FBR grade 316 stainless steel were revised based on the data-base consisted with low cyclic fatigue and tensile test data. 

Because the corrosion resistance of these stainless steels is dependent upon the chromium content, and because the carbon contents are generally higher than the ferritic alloys, it is logical that they are less corrosion resistant. However, their useful corrosion resistance in mild environments coupled with their high strengths made members of the martensitic family useful for certain stainless steel applications. Details of the specific family members are covered in Chapter 9. 

Fig. 8.15 A facility for manual electroplating. The modular equipment is suitable for both rack- and barrel-plating. Construction materials include corrosion-resistant PVC-clad steel and stainless steel. Applications include precious-metal plating in the electronics industry. Power supply and control circuitry are located above the tanks. (Courtesy PMD Chemicals Ltd.)...

Application of ceramics allows using stainless steel as vacuum envelope. No surface charges ean deflect the electron beam. Mechanical elements and functions can be easily integrated into the envelope due to its stability. 

Stirrers are usually made of glass, but those of monel metal, stainless steel or Teflon (a polyfluoroethylene) also find application in the labora tory. An important advantage of a stirrer with a Teflon blade is that it is... 

Another sol—gel abrasive, produced by seeding with a-ferric oxide or its precursors, has been patented (30). A magnesium-modified version of this abrasive, also called Cubitron, is being produced as a replacement for the earlier type. Yttria [1314-36-91-vnc>A V eA sol—gel abrasives have also been patented (31), as well as rare earth oxide modified materials (32). These abrasives are all produced by 3M Corporation they have performed very well ia various applications such as ia coated abrasives for grinding stainless steel and exotic alloys. 

Rigid Porous Media These are available in sheets or plates and tubes. Materials used include sintered stainless steel and other metals, graphite, aluminum oxide, silica, porcelain, and some plastics—a gamut that allows a wide range of chemical and temperature resistance. Most applications are for clarification. 

Disk Filters A disk filter is a vacuum filter consisting of a number of vertical disks attached at intervals on a continuously rotating horizontal hollow central shaft (Fig. 18-127). Rotation is by a gear drive. Each disk consists of 10 to 30 sectors of metal, plastic, or wood, ribbed on both sides to support a filter cloth and provide drainage via an outlet nipple into the central shaft. Each sector may be replaced individually. The filter medium is usually a cloth bag slipped over the sectors and sealed to the discharge nipple. For some heavy-duty applications on ores, stainless-steel screens may be used. 

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. 

These alloys have extensive applications in sulfuric acid systems. Because of their increased nickefand molybdenum contents they are more tolerant of chloride-ion contamination than standard stainless steels. The nickel content decreases the risk of stress-corrosion cracking molybdenum improves resistance to crevice corrosion and pitting. 

In this chapter we look first at an important class of alloys designed to resist corrosion the stainless steels. We then examine a more complicated problem that of protecting the most advanced gas turbine blades from gas attack. The basic principle applicable to both cases is to coat the steel or the blade with a stable ceramic usually Cr203 or AI2O3. But the ways this is done differ widely. The most successful are those which produce a ceramic film which heals itself if damaged - as we shall now describe. 

Fig. 1.3. The fire grate, which carries the white-hot fire inside the firebox, must resist oxidation and creep. Stainless steel is best for this application. Note also the threaded monel stays which hold the firebox sides together against the internal pressure of the steam.

Furnace tubes, piping, and exchanger tubing with metal temperatures above 800°F now tend to be an austenitic stainless steel, e.g., Type 304, 321, and 347, although the chromium-molybdenum steels are still used extensively. The stainless steels are favored beeause not only are their creep and stress-rupture properties superior at temperatures over 900°F, but more importantly because of their vastly superior resistance to high-temperature sulfide corrosion and oxidation. Where corrosion is not a significant factor, e.g., steam generation, the low alloys, and in some applications, carbon steel may be used. 

Flexible tubing for high pressure service, equipped with stainless steel overbraid plus tube adapter end connections, is commonly available with a carbon black-loaded PTFE core tube to dissipate static. Numerous other designs of conductive and antistatic tubing are available for low pressure applications. The utility of conductive tubing in preventing fires during transfer of aromatic hydrocarbon liquids is described in [165]. 

Some of the most obvious examples of problems with gas and materials are frequently found in refining or petrochemical applications. One is the presence of hydrogen sulfide. Austenitic stainless steel, normally a premium material, cannot be used if chlorides are present due to intergranular corrosion and subsequent cracking problems. The material choice is influenced by hardness limitations as well as operating stresses that may limit certain perfonnance parameters. 

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