Radial clearance

The labyrinth sleeve can be flexibly mounted to permit radial motion for self-ahguiug effects. In practice, a radial clearance of under 0.008 is difficiilt to achieve. 

Dry-friction whiri. This type of whip is experienced when the surface of a rotating shaft comes into contact with an unlubricated stationary guide. The effect takes place because of an unlubricated journal, contact in radial clearance of labyrinth seals, and loss of clearance in hydrodynamic bearings. 

Radial clearance has increased more than 1 mils over nominal design clearance. 

D/T = 0.5 / -inch radial clearance Blend time—equal Heat transfer coefficient—equal ... 

D - shaft diameter, in h - radial clearance, in Pq = high side pressure, psia T(, = temperature, °R R -- specific gas constant n = number of rings in series a = parameter, function of p po (see Figure D-7)... 

Wearing plates With open type impellers or end clearance wearing fits, these perform the same purpose as wearing rings do with radial clearances. 

R = ratio OD/ID of the tubing r = tubing and casing radial clearance in in. 

Larger radial clearance than rolling element... 

For shafts that require sleeve gaskets to pass over threads, at least 1.5 mm (0.06 in.) radial clearance shall be provided between the threads and the internal diameter of the gasket, and the diameter transition shall be chamfered in accordance with 2.2.10. 

The seal chamber shall conform to the minimum dimensions shown in Table 2-3. With these dimensions, the minimum radial clearance between the rotating member(s) of the mechanical seal and the bore of the seal chamber and gland shall be 3 mm (0.12 in.) (see Appendix U). 

Radial clearances. Radial clearance between the bushing and the shaft and the length of the bushing must be selected to obtain minimum leakage without exceeding fluid temperature limitations. 

The channel-depth profile is shown in Fig. 6.44. Between points Bi and B2 over an angle equaling the tip of flight a, the channel depth is constant and has a maximum value of H = 2Rs — Cl, between points A and P, namely, over the tip of the flight, the channel depth is zero (i.e., equals the radial clearance that is neglected in this analysis). Between points B and A the channel depth varies with the angle y as follows ... 

Fig. E7.9a Mixing of unmatured linoleum compound between concentric cylinder mixers, (a) Method of loading—initial condition, (b) After one revolution, (c) After 20 revolutions. Diameter of inner cylinder, 1 in radial clearance, 0.25 in. [Reprinted by permission from J. T. Bergen et al., Criteria for Mixing and the Mixing Process, paper presented at the 14th National Technical Conference, Society of Plastics Engineers, Detroit, 1958.]...

Helical screws operate in the laminar range at normally high impeller to vessel diameter ratio (DA/DT) with a radial clearance equal to 0.0375 Da. The impeller usually occupies one-third to one-half of the vessel diameter. They function by pumping liquid from the bottom of a tank to the liquid surface. The liquid returns to the bottom of the... 

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