Out-of-round

The actual number of tubes to be installed in the unit. Manufacturing tolerances may require elimination of some tubes that preliminary design layouts and tables indicated might be installed in the unit. Figures 10-25A-Kand Table 10-9 have considered known fabrication tolerances. Sometimes extra tie rods for baffles must be added, or in some cases, eliminated. The outer tube circle limit for each exchanger is determined by the type of shell to be used. That is, (1) if commercial pipe, greater out-of-round tolerances might be required or (2) if formed on shop rolls, the out-of-round tolerance will be known, but not necessarily the same for each diameter shell. 

Oil foaming Out-of-round shaft Excessive shaft deflection Uneven shimming of Contamination housing with loss of clearance Operating beyond grease life... 

Any out-of-roundness in a shell after fabrication will significantly reduce the ability of the vessel to resist external pressure. A deviation from a true circular cross-section equal... 

Variations of the O.D. include any possible distortion of the tube diameter. This distortion is referred to as out of round or API (all points in). For example, 20-mm tubing has a potential variation of 0.6 mm. The wall thickness for this tubing is 1.2 mm with a potential variation of +0.1 mm. The range of variations can be seen in Table 3.7. Although there can be a range of 2.2 mm (+1.1) on the inside diameter of a 20-mm tube, most manufacturers maintain their tolerances within half of these amounts. 

Table 3.7 Ranges of Variations of Outside Diameter Due to Out of Round...

To determine the DRB the following equation is used where the value of the DRB ranges around one with the close to one. Outside the set limits can cause at least out of round and plastic degradation ... 

Wrap a piece of tape around the 15/64" drill bit, 1-1/8 from the front. Carefully drill out the barrel to the depth of the tape mark, USe plenty of oil and don t let the hole become out of round. This drilling won t enlarge the barrel, it just removes the lands which cause the bullet to spin. It also removes the burrs caused by drilling the 1/8" holes. The undrilled portion of the barrel will still impart the needed spin, when the bullet reaches the drilled portion it is better to have the surface smooth to minimize bullet distortion as H passes the drilled holes. If a 15/64 drill is not a-vailable, a % may be used,... 

The ASME Boiler and Pressure Vessel Code, Division VIII, Section 1, Paragraph UG-81 permits an out of roundness maximum of 1% variation of all diameters from the nominal diameter. This is not sufficient to assure a satisfactory CRM lining. A German standard DIN 28050, Section 4 (10.54 issue) specifies that the roundness shall be determined by measuring the radians and that the radians must not vary more than +0.4% from the average value in the cylindrical part of the apparatus to be CRM lined after final erection. 

The ASME Code (Paragraph UG-81) permits a V/2% out of roundness of the flanges, but does not mention the out of roundness of the bodies of the nozzles themselves. Where these nozzles are to be sleeved, the out of roundness must be limited to 0.4%. (Reference 8, p 73). 

Note In brick lining vessels, it is not a matter of particular concern that vessels be perfectly plumb. If the vessels have floating heads, then the piumbness does become very important. It is more critical for out work that we have the center line established, and then our other criteria, namely, out-of-roundness will tell us if the steel is acceptable for receiving a chemically-resistant masonry lining. 

Figure 3-5 Allowable out-of-roundness of cylindrical shells to be lined. A = greatest diameter, B = smallest diameter, A - B < 0.75%A. Template length = (OS m) or 5% of circumference, whichever is greater. Maximum deviation from true arc = /is" (1.6 mm), except / " (3.2 mm) permitted at longitudinal (not circumferential) welds.

Nozzles to be sleeved in brick-lined vessels/tanks must be limited to 0.4% out-of-roundness. 

Column out-of-roundness or other irregularities may make it necessary to reduce or increase the width of some center blocks. This is accomplished by removing or adding a few strips of the packing material (342). The author is familiar with cases where strip removal was needed due to a tight fit. 

Radial runout Difference between the maximum and minimum measurements on the tread surface and in a plane perpendicular to the spin axis while the tire is mounted on a wheel. It is a measure of the out-of-roundness of the tire. It can also be termed centerline runout. ... 

Mekid S, Vacharanukul K (2011) In-process out-of-roundness measurement probe for turned work-pieces. Measurement 44 762-766... 

Turbine exhaust (representative of all horizontal turbocompressor seals). E-seal Segmented cylindrical piston ring. Available in large diameters Accommodates relative motions and out of roundness Low development risk... 

Excessive stuffing box packing wear insuffident lubrication/excessive shaft wobble/shaft is out of round/improper packing installation and maintenance. 

Out-of-roundness can be negatively affected by the stiffness of the machine tool, not only as a result of the grinding operation. 

While the upper collimated light serves as the measuring beam, the lower portion impacts on the second photodetector and acts as the reference beam. Thus, the temperature and age affected by drift which occurs on all semiconductor elements is negated. In some applications such as hose and tubing manufacturing, it is important to know both the extrudate diameter and cross-section. The device described can provide two diameter measurements, which will give an out-of-round indication (eccentricity). 

In general, difficulties encountered with eccentric or out-of-round coils are more pronounced when slitting light- to medium-gauge, heavier coils that are loosely wound and not on sleeves or cores. 

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