Steel weld construction

A block mold consists mostly of a rectangular-shaped steel weld construction of which one side is built as a door that has to completely release the block side surface to demold the block. 

Piping. Specify materials—stainless steel has numerous advantages. Specify welded construction and the minimum use of fitting. Tape-type thread lubricants should be avoided. 

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) ... 

The housing is streamlined in design to give good air flow characteristics, ft may be of riveted welded or bolted metal sheets. The usual material is steel, although construction is available to meet corrosion conditions described for the wheel. 

The tanks will normally be of fully welded construction from mild steel with the internal surfaces shot blasted and a protective plastic coating applied. It is important that all... 

Estimate the thickness required for the component parts of the vessel shown in the diagram. The vessel is to operate at a pressure of 14 bar (absolute) and temperature of 300°C. The material of construction will be plain carbon steel. Welds will be fully radiographed. A corrosion allowance of 2 mm should be used. 

Cement-lined pipe in sizes smaller than 1 Vk in is not generally recommended. Cement-lined carbon steel pipe can be supplied with butt-weld or flanged ends. Butt-welded construction involves the use of special joint grouts at the weld joint and controlled welding procedures. See Table 10-40. 

The pressure vessels are hollow cylinders, of 100- to 10,000-liter capacity, having a flange onto which the cover is fastened by means of bolts and nuts. The bottom of die vessel is usually hemispherical for greater strength. Autoclaves are almost always made of iron, either cast steel or cast iron, the former being safer to use at high pressures. Sheet iron is also used, in wall thicknesses up to 40 mm., in either riveted or welded construction. The reluctance in many dye plants to use welded autoclaves is entirely unjustified and has arisen simply because in the early days of the industry welding processes had not been perfected. 

C. The material of construction will be plain carbon steel. Welds will be fully radiographed. A corrosion allowance of 2 mm should be used. 

Techniques for handling sodium in commercial-scale applications have improved (5,23,98,101,102). Contamination by sodium oxide is kept at a minimum by completely welded construction and inert gas-pressured transfers. Residual oxide is removed by cold traps or micrometaUic filters. Special mechanical pumps or leak-free electromagnetic pumps and meters work well with clean liquid sodium. Corrosion of stainless or carbon steel equipment is minimized by keeping the oxide content low. The 8-h TWA PEL and ceiling TLV for sodium or sodium oxide or hydroxide smoke exposure is 2 mg/m3. There is no defined AT P for pure sodium, as even the smallest quantity ingested could potentially cause fatal injury. 

European designers and fabricators frequently avoid Type 304 steel for welded construction on the grounds that it may be subject to weld decay. The titanium-stabilized Type 321, which (in contrast to the situation in the United States) is only slightly more costly than 304, is often preferred. 

The vacuum chamber (Fig. 2) is a 20 x 39-in. stainless steel cylinder of all heliarc-welded construction. The chamber is suspended in an insulated aluminum tank. The chamber volume after correction for the pump lines and cryosphere was calculated to be 202 liters. This chamber size makes possible the use of commercially available standard leaks, without introducing significant errors in the time measurement when calibrating the gas analyzer by the rate of pressure rise method. The 7-in.-diameter cryosphere has a calculated surface area of 995 cm . The coolant transfer lines to the cryosurface are vacuum-jacketed to prevent possible condensation. 

Extruder housing Version extruder machine body and gearbox separate, or as unit Design open ribbed-type construction, enclosed double-walled box section, self-contained design, fitted on base frame Material welded construction, cast iron, spheroidal graphite cast iron, cast steel... 

Material welded construction, cast steel, cast steel with wear-resistant rims, Nihard, highly wear-resistant special casting, hard-faced augers, stainless steel design ... 

Hardening is not necessary, and chrome plating is not customary. For large-volume parts with a content of 4 cu yd (3 cu m) and up, welded machined steel plate construction can be considered. Cast metal is of no value for the mold bases. Given the right care, the life of steel molds is the longest, at over 10 parts per mold. Inserts subject to wear and tear have to be either refurbished or exchanged at intervals of 10 or 10 cycles (Table 4-10). 

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