Weldable materials

Turbo blower 0.1-10 2 20 all weldable materials e.g., stainless steel, monel, titanium, nickel, etc. (also plated or rubber-coated)... 

Headed anchor rods may be used in heu of headed studs to increase the embedment and assure ductile design, or if studs are not available. Design is similar to that for headed studs. The user must ensure that the anchor rod is made of a weldable material. 

Construction. Dry scrubbers are constructed of carbon steel in accordance with the ASME Code however, they can be built of almost any weldable material. 

When both components of a threaded joint are of weldable metal, the joint may be seal-welded as shown in Fig. 10-130. Seal welds may be used only to prevent leakage of threaded joints. They are not considered as contributing any strength to the joint. This type of joint is limited to new construction and is not suitable as a repair procedure, since pipe dope in the threads would interfere with welding. This method provides tight joints with a minimum of welding labor. When threaded joints used to join materials with widely dinerent coeffi-... 

Filler metal is required to conform with the requirements of Sec. IX. Backing rings (of ferrous material), when used, shall be of weldable qiiahty with sulfur hmited to 0.05 percent. Backing rings of non-ferroiis and nonmetaUic materials may be used provided they are proved satisfactory by procediire-qnaJification tests and provided their use has been approved by the designer. 

Fixed-Tube-Sheet Heat Exchang ers Fixed-tube-sheet exchangers (Fig. 11-36Z ) are used more often than any other type, and the frequency of use has been increasing in recent years. The tube sheets are welded to the shell. Usually these extend beyond the shell and serve as flanges to which the tube-side headers are bolted. This construction requires that the shell and tube-sheet materials be weldable to each other. 

Material Moist, e.g.. chlorine below dew point F)ry, e.g., fluorine above dew point Hydrogen halides, dry,J e.g., dry hydrogen cliloride, F Available forms Cold formability in wronglit and clad form Weldability Maximum strength annejiled condition x 1000 Ib/in- Coefficient of thermal expansion, millionths per F, 70-212 F Remarks ... 

Production platforms are coated only in exceptional cases or for the purposes of investigation because the life of the structure is greater than the life of the coating. Therefore in the design of the cathodic protection, only the protection potential Us of the steel need be considered. Steels with an ultimate tensile strength of up to 350 N mm are used for these structures, which are weldable even in thick sections, and the hardness of the welded material can be kept to 350 HV (see Section 2.3.4 [2,10]). Aluminum anodes with the same protection effect and life as zinc anodes have much less weight. This is a very important advantage for... 

Somewhat between PTFE and PFA materials is the product Hostaflon TFM, which is a copolymer of TFE and a small amount of the perfluoro(propyl vinyl ether). It has improved impact strength and weldability and has been promoted as a suitable material for forming into bottles. Yet another TFE-perfluoroalkoxy copolymer was introduced by Du Pont in 1979 as Teflon EPE. This material had a somewhat lower melting point (295 °C) than the more common PFA fluoropolymers but it is no longer marketed. 

Mild steel (<0.25% carbon) is the most commonly used, readily welded construction material, and has the following typical mechanical properties (Grade 43A in BS4360 weldable structural steel) ... 

These elements that insert in a pipe or specially fabricated cylindrical holder can usually be fabricated from any workable and weldable metal or alloy. In addition, most plastic that can be fabricated by molding, cutting, heat welding, or even bolting can be used. This wide array of fabrication materials allows the units to fit an extremely wide range of corrosive applications. 

There is no guarantee that crack-free joints will automatically be obtained when fabricating weldable metals. This is a result of the fact that weldability is not a specific material property but a combination of the properties of the parent metals, filler metal (if used) and various other factors (Table 9.7) . The consequence of the average structural material possessing imperfect weldability is to produce a situation where defects may arise in the weld deposit or heat-affected zone (Table 9.8 and Fig. 9.27). 

Space does not permit a survey of all the various weldable metals and their associated problems, although some suggestions are made in Table 9.9. It is sufficient to state that with a knowledge of the general characteristics of the welding process and its effects on a metal (e.g. type of thermal cycle imposed, residual stress production of crevices, likely weldability problems) and of the corrosion behaviour of a material in the environment under consideration, a reliable joint for a particular problem will normally be the rule and not the exception. 

Filled polyethylene separators are the only pocket material that has been able to meet all requirements of a starter battery reliably [39-48]. It is flexible and weldable into three-sided closed pockets, making the previously usual mud room at the bottom... 

Material used for reinforcement may differ from that of the run pipe, provided it is compatible with run and branch pipes with respect to weldability, heat treatment requirements, galvanic corrosion, thermal expansion, etc. 

These materials are normally microalloyed with Cb, V, and/or Ti. Supplemental specifications agreed to by manufacturer and purchaser commonly establish chemistry more restrictive than the base specification, as well as plate rolling specifications and requirements for weldability (i.e., C-equivalent) and toughness. 

In late 1989, the availability of a proprietary family of weldable, high-strength Weldcdite) A1 Li products appeared. The material was claimed to be. nearly twice as stiong (100 >. 1(V psi) as othei leading alloys then... 

The cost considerations involve factors such as raw materials, quantities, production cost with respect to weldability, formability and machinability, labor requirements and anticipated service life. Ready availability of the material depends on whether the material is made to order, or readily bought from the manufacturer, or bought off the shelf, and whether any tooling is required to meet the specific standards. 

---