Outer diameter and wall thickness

As mentioned earlier, the outer diameter is related to the inner diameter. 

Up to ultimate pressures of about 400 atm, the wall thickness of 316 stainless-steel columns is not so critical, but when larger pressures are applied, the ratio of 

In an attempt to use glass columns at higher pressures, an ingenious glass 

The inner surface of glass columns is usually smooth and no further pre-treatment is necessary. In some instances the inner surface is etched this has no significant effect on the column efficiency in comparison with the smooth-surface type of glass tubes, but in practice, etched glass tubes have a slightly better pressure resistance. 

In HPLC, straight columns are usually applied, in contrast to gas chromatography 

---

Characteristics of the hollow fiber membrane is shown in Table 2. The outer diameter and wall thickness of this hollow fiber membrane is fairly thick compared with those of other hollow fibers for seawater desalination. Salt rejection of hollow fiber membrane is high enough to be applied to one pass seawater desalination. 

The constituents of natural gas should not have deleterious effects on the pipe properties, nor should the gas diffuse through the pipe wall at an excessive rate. Methane and the other hydrocarbons in natural gas, diffuse through polyethylene at a very low rate, that neither causes economic loss, nor dangerous build-up of gas on the outside of the pipe. The maximum daily loss from 1 km of pipe, of 90 mm outer diameter and wall thickness 8.5 mm, pressurised to 1 bar pressure (the partial pressure of methane is 2 bar inside and Obar outside), is 4.41. This is less than 1% of the losses that occur with jointed cast iron pipe, and can be compared with a daily throughput of 2 x 10 1 of gas for a pressure drop of 1 mbar km . ... 

Guiding channels (GC) for absorbing elements are optimised by outer diameter and wall thickness. The aim was to improve the conditions of insertion of absorbing elements under the... 

Dimension tests for bottles assess height, outer diameter, and wall thickness, determined in accordance with ASTM D 2911 or JIS Z 1703. 

Both these dimensions are of practical importance in the use of the hollow fibres for gas separation. The results given in this section show how five variables in the spinning conditions affect the outer diameter and wall thickness of the hollow fibres. The outer diameters of the fibres produced in the study ranged between 0.36 - 1.0 mm, and the wall thickness of the fibres between 0.01 and 0.07 mm. 

Effects of Spinning Parameters on The Outer Diameter and Wall Thickness... 

For a hollow cylintfer exposed to a convection environment on its inner and outer surfaces, the electric-resistance analogy would appear as in Fig. 2-6 where, again, 1A and TB are the two fluid temperatures. Note that the area for convection, is not the same for both fluids in this case, these areas depending on the inside tube diameter and wall thickness. In this case the overall heat transfer would be expressed by... 

It is assumed that process conditions and physical properties are known and the following are known or specified tube outside diameter D, tube geometrical arrangement (unit cell), shell inside diameter D shell outer tube limit baffle cut 4, baffle spacing and number of sealing strips N,. The effective tube length between tube sheets L may be either specified or calculated after the heat-transfer coefficient has been determined. If additional specific information (e.g., tube-baffle clearance) is available, the exact values (instead of estimates) of certain parameters may be used in the calculation with some improvement in accuracy. To complete the rating, it is necessary to know also the tube material and wall thickness or inside diameter. 

The data of Tables 2 and 3 show that palladium-ruthenium alloys with mass % of ruthenium from 4 to 7 have high hydrogen permeability, catalytic activity toward many reactions with hydrogen evolution or consumption, and good mechanical strength [35]. Seamless tubes with a wall thickness of 100 and 60 p.m, as well as foils of 50-tim thickness made of the mentioned alloy, are commercially available in Russia. The tube of outer diameter of 1 mm and wall thickness of 0.1 mm is stable at a pressure drop of up to 100 atm and a temperature up to 900 K. The application of such tubes for membrane reactor will be discussed in next part of this section. 

Example 4.2 In a tube bundle condenser, like that sketched in Fig. 4.11, 7 103kg/h saturated vapour of refrigerant R22, at a pressure of 1.93 MPa is to be condensed. Cooling water is available at a temperature of 18 °C, and this can be heated by 10K. Copper tubes of length 1.5 m, 16 mm outer diameter and 1 mm wall thickness are to be used in the construction of the condenser. 

I-CVI has been widely used to manufacture carbon/carbon braking disks since the 1960s. In a common application as shown in Figure 5.16, multicylindrical carbon brake disk preforms, typically 550 mm in outer diameter and 20 to 30 mm in thickness, are placed in a hot-wall reactor at a temperature of 1000°C and exposed to the CH4 precursor at a pressure of lto 30 kPa [29],... 

Die land forms the outer diameter of the tubular extrudate, held in place with a retaining ring and position adjusted with centering bolts. The die land can be changed to create a tube of a different diameter or wall thickness while keeping the original die pin. 

Trunec has described the thermoplastic extrusion of thin-wall tubes made of yttria-stabilized zirconia and gadolinia-doped ceria [Tru 04], These ceramics are used for solid oxide electrolyte applications, e.g. solid oxide fuel cells. The thermoplastic binder system used consists of ethylene-vinyl acetate copolymer, parafHn wax and stearic acid. With this system tubes with an outer diameter of 10.5 mm and wall thicknesses of 290 and 280 pm could be fabricated. 

The glass microballoons were obtained from Potters Industries (Q-CEL6014, average outer diameter 85 pm, bulk density 0.08 g/cm, effective density 0.14g/cm, maximum working pressure 1.73 MPa, and wall thickness 0.8 pm). These raw materials have been used previously for the smart syntactic foam [38] and conventional epoxy based syntactic... 

The UO, rods consisted of O.SOO-in. diam sintered pellets stacked in 6063 aluminum tubes 0.020 in. thick and 0.547 in. OD. The oxide density averaged 10.39 g/cc. These rods were used to build up three types of clusters.-containing 19, 31, and 48 rods in triangular arrays. The six flat boundaries of the 46-rod cluster alternated between rows of four rods and five rods. The center-to-center rod spacing averaged 0.650 in. in the 19- and 31-rod clusters and 0.656 in, in the 48-rod clusters. Three sizes of 6063 aluminum housing tubes were used, They had outer diameters of 4.0, 5.0, and 6.0 in. and wall thicknesses of 0.054, 0.056, and 0.058 in. respectively. 

Clusters are in the form of a bundle of 18 absorber rods joined by a common traverse, moving inside the E-635 zirconium-alloy guide tubes of a 12.6 mm outer diameter and a 0.6 mm wall thickness. Each cluster has its own drive. On the total, there are 72 control rod clusters of the reactor control and protection system (CPS). The core map is shown in Fig. VII-10. 

Example 4.5. A titanium pipe (ASTM B265 Gr. 5) with a 2.375-in. outer diameter and a 0.154-in. wall thickness has an actual stress of 30 ksi, a yield stress of 120 ksi, and K,q = 40 ksiVim at a given temperature. The pipe contains a flow of depth 0.05 in. and length 0.25 in., which is similar to case 6 of Table 4.8. What is the maximum internal pressure the pipe can hold ... 

The loss of material reduces the available load-bearing cross-section, so that as oxidation proceeds, the stresses acting on the component increase. The magnitude of the effect will, of course, depend on the initial wall thickness for thick-walled components, such as steam headers (30-50 mm wall thickness), a 1 mm loss will not be very significant, but a similar material loss in a thin-walled tube of say 5 mm wall thickness would have grave repercussions for the service life [10]. Figure 11.11 illustrates this for a P92 pipe (300 mm outer diameter and 40 mm wall... 

---