Fillets radii

Optimize design to reduce cost or satisfy functional and performance requirements General configuration Configuration proportions such as rib depths, shell radii, fillet radii, etc. Material thickness Material alternatives—consider additives to tailor properties Process alternatives... 

All shaft keyways shall have fillet radii conforming to ASME B17.1. 

Figure 4.8 also presents an analytical solution for the screw characteristic curve of a single screw extruder with leakage flow effects. The discrepancies between analytical solution and experimental results arise due to the fact that the screw curvature, the flight angle and the fillet radii are not included in the analytical model. The analytical solution given by Tadmor and Klein [27] was used. 

The dependence of these functions (2.a) and (2.b) on the relative notch length for specimens with different fillet radii at the notch base (i.e. sharp cornered and fully rounded) is shown in Fig. 3. 

Corner and fillet radii should be as large as possible to facilitate metal flow and minimize die wear. Usually 6 mm (0.24 in.) is the minimum radius for parts forged from high-temperature alloys, stainless steels, and titanium alloys. 

Aramid fiber is also used in production of reinforced thermoplastics (RTPs), as commingled yarns or a hybrid yarn or fabric, suitable for high drapabihty and coping with very sharp fillet radii, and in specialty tires. 

Design of the part itself (fillet radii, angles, etc.)... 

Webs and other plates elements 1.49 side for box flanges Distance between lines of welds or bolts for flange cover plates Clear distance between flanges minus fillet radii for webs of rolled... 

Bosses are used to reinforce holes in the part and to provide mounting locations. Solid bosses are called studs. Bosses must be molded with rounded corners and adequate fillet radii. They usually are located in a corner or juncture of two or more surfaces to minimize the effects of sinking. The problem of shrink marks is lessened with GRTP because of their reduced shrinkage. It is generally recommended that the height of the boss be limited to twice its diameter. Vertical surfaces should have at least a 1 deg draft per side. Recommended designs are shown in Fig. 6-5. 

Fillet radii should be as generous as possible to minimize the occurrence of hot tears. While 0.76 mm (0.030 in.) radii are produced, the preferred minimum is 3.0 mm (0.12 in.). Arule of thumb is that a fillet radius should be 0.5 times the sum of the thicknesses of the two a4ioining walls. 

Rg. 4 Comer and fillet radii for various materials recommended by forging users and producers. Source T.AItan etal., Forging Equipment, Materials, and Pracdoes, MClC HB-03, Battelle, 1973... 

Draft, comer, and fillet radii, and minimum section thicknesses and maximum rib heights... 

Comer and Fillet RadiL Proper selection of comer and fillet radii is critical in avoiding metal flow problems such as laps, cold shuts, and flow-through defects in structural rib-web foigings and other parts with deep cavities. 

As with draft angles, exact values of comer and fillet radii cannot be quoted, is... 

The first precision forged titanium alloy products commerdally produced were turbine engine compressor and fan blades conventional forging process techniques were used. With hot-die/isother-mal forging techniques, very complex cross-section predsion forged airfi ame components are being manufactured. Titanium alloy predsion forgings are produced with very thin webs and ribs sharp comer and fillet radii imdercuts, back-draft, and/or contours and, fiequently. 

Fillet radii should be not small to reduce stress concentrations, but also that the fillet radius does not disappear due to shririkage [a]. The wall thickness should be constant to reduce cycle times and also to reduce stress concentrations. 

In Figure 8A-B an improved design is presented with sufficient fillet radii, a fastening hole closer to the wall and a rib to transfer the load more gradually to the wall. 

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