Bolts, design specifications

Depending upon size and type of unit, the mounting may vary from simply bolting to the floor to attaching to a massive foundation designed specifically for the application. A proper foundation must (1) maintain the alignment and level of the compressor and its driver at the proper elevation, and (2) minimize vibration and prevent its transmission to adjacent building structures and machinery. There are five steps to accomplish the first objective ... 

Close inspection of contractors work is important in order to ensure that design specifications are being followed. This includes checking for use of correct bolts (size, strength, etc.), correct size and spacing of rebar, specified type and thickness of silo walls, etc. 

Unstayed flat heads and covers can be designed by very specific rules and formulas given in this subsection. The stresses caused by pressure on these members are bending stresses, and the formulas include an allowance for additional edge moments induced when the head, cover, or blind flange is attached By bolts. Rules are provided for quick-opening closures because of the risk of incomplete attachment or opening while the vessel is pressurized. Rules for braced and stayed surfaces are also provided. 

Torsional test and minimum torques for bolts and screws with nominal diameters I mm to lO mm Specification for spring washers for general engineering and automobile purpo.ses, Metric series Code of practice for design of high-voltage open-terminal stations... 

Specific supporting parameters are illustrated in Figure 3 M24-22 mm x 2400-type anchor bolt which is composed of high strength twist steel and >17.8 mm x 6500-type anchor cable. The space between anchor bolts should be controlled at 800 mm x 800 mm. The pre-tension torque of the anchor bolts is designed to be more than 300 N m. Also, 12 rhombic metal mesh and W steel belt are used in the supporting system and the spray layer should be 30-50 mm thick. 

Physical dimensions of many processed parts must be held to fairly close tolerances to ensure proper assembly of parts into a complete structure, as, for example, molded fender panels bolted to steel chassis cars, plastic screw caps for glass jars, etc. In general, the final dimensions of the processed part will differ from the dimensions of the mold cavity or the pultrusion die. Such differences are somewhat predictable, but are usually unique to the specific material and to the specific process. The dimensions of a mold cavity for a phenolic part requiring close tolerances will often be different from dimensions of a cavity for an identical polyester part. Both the part designer and the mold or die designer must have a full understanding of the factors affecting final dimensions of the finished product, and often need to make compromises in tolerances of both part and cavity dimensions (or even in plastic material selection) in order to achieve satisfactory results with the finished product. 

The part assembly design addresses the ability to join/assemble the component parts. Where the components are assembled with adhesives, it is important to know the compatibility and strength of adhesion to dissimilar substrates, in addition to the chemical compatibility of the plastic with the specific adhesive and its constituents. If melt bonding methods, like ultrasonic, vibration, or spin-welding processes, are employed, thermal compatibility aspects have to be taken into account. The broad possibilities of mechanical assembly methods include snap fits, press fits, bolts, and threads. The material properties needed for each of these design calculations are listed in Table 11.9. 

For major component support bolting applications (e.g., reactor vessel, steam generator, etc.), the bolts are designed and fabricated to ASME Section III requirements with proven materials chosen for the specific application and environment (see CESSAR-DC, Section 3.9.3)... 

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