Eccentric reducers

Other Hf — Hf reduction eccentric reducer concentric incre.iser... 

Use an eccentric reducer with the flat side up (to prevent trapping vapor) as the transition from the larger suction line to the pump suction nozzle. 

Concentric reducers should not be used to reduce suction piping diameter to that of the pump s inlet flange. This type of reducer may create an air pocket in the top of the piping and could lead to loss of pump performance resulting from air entrainment. Eccentric reducers should be installed with the straight side on top. This will reduce the potential for air pocket in the piping or the introduction of air or gas into the pump. 

Eccentric reducers not in accordance with para. IP-3.1 shall be qualified as required by para. IP-3.8.2. 

FIGURE 3-9. Installation of Pump Suction Reducers. (a,b) Concentric reducer can allow formation of pocket of undissolved gases when pump is shot off. This produces cavitation at startup. This reducer also can allow sedimentation of hazardous solids in the line during shutdown. (c,d) Installation of eccentric reducer in this orientation eliminates gas pockets. (e,f) This orientation prevents sedimentation. 

Poor performance can result from fan inlet eccentric or spinning dow, and discharge ductwork that does not permit development of hiU fan pressure. Sometimes inlet restrictions starve a fan and limit performance. To obtain rated performance, the air must enter the fan uniformly over the inlet area without rotation or unusual turbulence. This allows all portions of the fan wheel to do equal work. If more air is distributed to one side of the wheel, such as with an elbow on the inlet, the work performed by the lightiy loaded portions of the wheel is reduced and capacity is decreased by 5—10%. The use of an inlet box duct on a fan can reduce capacity by as much as 25% unless there are turning vanes in the duct. Use of the vanes reduces the capacity loss to around 5%. 

In 1971 a metal-backed polyethylene acetabular cup was introduced. This cup provided an eccentric socket which was replaceable, leaving the metal and replacing only the polyethylene. Because of the success of this component, metal-backed high density polyethylene (HDPE) liner is standard for prosthetic acetabular components. Research confirms that metal-backing reduces the peak stresses in the bone cement, and that HDPE forms a successfiil articulating surface for the prosthetic joint. 

A high-performance biitterllv valve has a disc that is offset from the shaft center line. This eccentricity causes the seating surface to move avv av from the seal once the disc is out of the closed position, reducing friction and seal vv ear. Also Icnovvn as an eccentric disc valve, its advantage is improved shutoff vvliile maintaining high ultimate capacity at a... 

There is a sudden reduction in the suction between the tank and the piping. There is an eccentric 6-to-4 reducer between the suction pipe and the pump. There is a eoneentrie 3-to-4 inereascr from the pump back into the piping, and a sudden enlargement going into the discharge tank. The formula is ... 

Use an eccentric pipe reducer to connect to the pump suction nozzle (Figure 17-17). 

Displacement sensors are used in a very wide field of applications in research, development, quality inspection, automation, machinery and process control. Many physical parameters can be reduced to a displacement or change of distance, and can be measured with highest precision. Displacement sensors detect physical parameters like bending, deflection, deformation, diameter, eccentricity, elongation, gap, length, play, position, revolution, roundness, shift, stroke, thickness, tilt, tolerances, vibration, wear and width. 

Levy et al. (L5) have studied the effect of eccentricity on the bum-out flux in upward vertical annular flow. Eccentricity does not affect the burn-out flux until the annular separation is about 20% or less of its concentric value. Bum-out fluxes for great eccentricities are increased about 30%, which is ascribed to poor fluid mixing pressure-drop at the same conditions is reduced. The small effect of moderate eccentricity in downward annular flow of steam-water mixtures was also reported earlier by Stein et al. (Sll) in their study of pressure-drop and critical flow. 

Reducers Reducers may be cast, forged, or hot- or cold-formed from pipe or plate. End connections may be concentric or eccentric, that is, tangent to the same plane at one point on their circumference. For pipe supported by hangers, concentric reducers permit maintenance... 

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