Pressure vessels calculation form

Standard calculation forms can save considerable time in pressure vessel design. These forms also systematize the mechanical design procedure to insure that nothing is omitted. Most engineering contractors have developed their own vessel calculation forms. Basically, all are alike in that they correlate, in easy-to-use fashion, the design rules set forth in Section VIII of the ASME Boiler and Pressure Vessel Code for Unfired Pressure Vessels. They also include design considerations not covered by the code, such as wind loading for tall vessels. (Text continues on p. 139.)... 

P(R + 0.5t)/t. Values obtained from the use of this form of the equation provide stress values within 2% of the values calculated using the more exact thick-walled pressure vessel formulas. 

Corrosion is generally considered to be in one of two forms uniform or localized. Uniform corrosion occurs evenly on all surface areas of a pressure vessel. Such corrosion occurring at slow rates is quite typical and can be planned for by increasing the original wall thickness design. For vessel systems with a predictable corrosion rate, allowances can be calculated for vessel life spans of 2-20 yr. ... 

The Data Sheet gives specifications for the design of a pressure vessel to be used as a reabsorber in a process plant. The design for this tower will be worked out by inserting known values from the calculation sheet and by solving pertinent equations shown on computation forms A through L. 

Similarly, Baers and Harsanen (1993) have determined the specific Nb activities in reactor pressure vessel steel (containing niobium in the ppm range) and plating ( 1% Mb). Niobium was isolated from the other radionuclides by ion exchange chromatography and ""Nb measured by liquid scintillation spectrometry niobium mass in the samples was determined by inductively-coupled plasma mass spectrometry. In this way, it was possible to rule out interferences caused by other radionuclides. However, the data to be used for the calculation of fast neutron fluence can be impaired by ""Nb which is formed by decay of Mo which is an (n,y) product of stable Mo. This interference becomes significant when the... 

Hellmann et al. (1991), in their experiments mentioned above, also measured the extent of iodine volatilization from the sump remaining in the low-pressure vessel after termination of a flash release test. From these measurements, a volume-related partition coefficient of about 2 10 was calculated at a water temperature of 60 to 80 °C, resulting in an iodine volatilization of less than 0.1% within 10 hours under the conditions prevailing in a transducer compartment. Thus, iodine release from the sump formed by the escaped primary coolant can be neglected in the evaluation of the consequences of such an accident. 

Already the first measurements performed in the containment about one day after the onset of the accident showed that the major fraction of fission product iodine was plated out in the sump water, while only a very smaU fraction was airborne in the containment atmosphere. Taking the different voliunes of both phases into account, an integral iodine partition coefficient of about 2 1(F was calculated from these data (Pelletier, 1980). The pH of the siunp water was about 8.6 (due to sodium hydroxide solution which was automatically injected into the containment sump to improve iodine retention in the liquid phase) the value of the partition coefficient is consistent with the data obtained in the CSE experiments, when the lower pH of the sump water in these experiments is taken into account. This high value indicates that in the TMI-2 accident the bulk of the fission product iodine was released from the primary circuit to the containment in the form of an iodide compound and not as elemental I2. This assumption is consistent with the observation made later on that only about 1% of the iodine present in the sump water was in the form of iodate it is also consistent with the redox conditions in the reactor pressure vessel which were mentioned above For such an H2 H2O... 

A formed section would normally be used for the transition between a cylindrical section and conical section except for vessels operating at low pressures, or under hydrostatic pressure only. The transition section would be made thicker than the conical or cylindrical section and formed with a knuckle radius to reduce the stress concentration at the transition, Figure 13.11. The thickness at the knuckle can be calculated using equation 13.46, and that for the conical section away from the transition from equation 13.45. 

Resistance functions have been evaluated in numerical compu-tations15831 for low Reynolds number flows past spherical particles, droplets and bubbles in cylindrical tubes. The undisturbed fluid may be at rest or subject to a pressure-driven flow. A spectral boundary element method was employed to calculate the resistance force for torque-free bodies in three cases (a) rigid solids, (b) fluid droplets with viscosity ratio of unity, and (c) bubbles with viscosity ratio of zero. A lubrication theory was developed to predict the limiting resistance of bodies near contact with the cylinder walls. Compact algebraic expressions were derived to accurately represent the numerical data over the entire range of particle positions in a tube for all particle diameters ranging from nearly zero up to almost the tube diameter. The resistance functions formulated are consistent with known analytical results and are presented in a form suitable for further studies of particle migration in cylindrical vessels. 

A technique frequently used to characterize the pressure state in the high vacuum regime is the calculation of the time required to form a monomolecular or monoatomic layer on a gas-free surface, on the assumption that every molecule will stick to fhe surface. This monolayer formation time is closely related with fhe so-called impingement rate z. With a gas at rest the impingement rate will indicate the number of molecules which collide with the surfece inside the vacuum vessel per unit of time and surface area ... 

A 0.500 L reaction vessel equipped with a movable piston is filled completely with a 3.00% aqueous solution of hydrogen peroxide. The H202 decomposes to water and 02 gas in a first-order reaction that has a half-life of 10.7 h. As the reaction proceeds, the gas formed pushes the piston against a constant external atmospheric pressure of 738 mm Hg. Calculate the PV work done (in joules) after a reaction time of 4.02 h. (You may assume that the density of the solution is 1.00 g/mL and that the temperature of the system is maintained at 20°C.)... 

---