Pressure vessels recommendations

For the design of internal-pressure cylindrical vessels, the API-ASME Code for Unified Pressure Vessels recommends the following equations for determining the minimum wall thickness when extreme operating pressures are not involved ... 

Catalytic Reduction. Catalytic reduction usually takes place in solution, emulsion, or suspension in autoclaves or pressurized vessels after the catalyst is added, the vessel is pressurized with hydrogen (32,33). Water and methanol are the preferred solvents. In water the addition of alkaU hydroxide (34), alkah carbonate (35), or acid (36) has been recommended. 

Sulfurization of unsaturated compounds and meicaptans is normally carried out at atmospheric pressure, in a mild or stainless steel, batch-reaction vessel equipped with an overhead condenser, nitrogen atmosphere, an agitator, heating media capable of 120—215°C temperatures and a scmbber (typically caustic bleach or diethanolamine) capable of handling hydrogen sulfide. If the reaction iavolves the use of H2S as a reactant or the olefin or mercaptan is a low boiling material, a stainless steel pressurized vessel is recommended. 

Sulfurchlorination of unsaturated compounds or mercaptans is normally carried out at atmospheric pressure in a glass-lined reaction vessel because of the potential to Hberate HCl during the reaction. The sulfurchlorination vessel is equipped with a cooling jacket or coils (very exothermic reaction), a nitrogen or dry air sparging system, an overhead condenser, and a caustic or bleach scmbber. If one of the reactants (olefin or mercaptan) is alow boiling material, ie, isobutylene, a glass-lined pressure vessel is recommended. 

Storage tanks should be designed in accordance with the ASME code for unfited pressure vessels. AH-welded constmction is recommended. Ethylene oxide storage tanks should be electrically grounded, isolated from potential fire hazards, and equipped with pressure rehef devices. New equipment should be cleaned of iron oxide and immediately purged with inert gas. 

All pressure vessels must pass appropriate hydrostatic testing before approval for service. For safety reasons, hydrostatic pressure testing is almost always recommended over a pneumatic test. The recommended... 

A series of utuaxial fatigue tests on unnotched plastic sheets show that the fatigue limit for the material is 10 MN/m. If a pressure vessel with a diameter of 120 mm and a wall thickness of 4 mm is to be made from this material, estimate the maximum value of fluctuating internal pressure which would be recommended. The stress intensity factor for the pressure vessel is given by K = 2hoop stress and a is the half length of an internal defect. 

The ASME code requires every pressure vessel that can be blocked in to have a relief valve to alleviate pressure build up due to thermal expan sion of trapped gases or liquids. In addition, the American Petroleum Institute Recommended Practice (API RP) 14C, Analysis, Design, Installation and Testing of Basic Surface Safety Systems on Offshore Production Platforms, recommends that relief valves be installed at vari ous locations in the production system and API RP 520, Design and Installation of Pressure Relieving Systems in Refineries, recommends various conditions for sizing relief valves. 

Many suppliers of sulfuric acid recommend that it is stored in pressure vessels designed to withstand a gauge pressure of 30 psi (2 bar). The acid is usually discharged from tank trucks by compressed air, and if the vent is ehoked the vessel could be subjected to the full pressure of the compressed air. 

This subject has received little attention in the context of pressure vessel bursts. Pittman (1976) studied it using a two-dimensional numerical code. However, his results are inconclusive, because the number of cases he studied was small and because the grid he used was coarse. Baker et al. (1975) recommend, on the basis of experimental results with high explosives, the use of a method described in detail in Section 6.3.3. That is, multiply the volume of the explosion by 2, read the overpressure and impulse from graphs for firee-air bursts, and multiply them by a factor depending on the range. 

It is recommended that all pressure vessels and atmospheric vessels be designed, fabricated, tested, and code stamped according to the most applicable code as ASME or API, regardless of service application (nuclear is excluded from any discussion in these chapters) ... 

It is recommended that computations of relieving loads avoid cascading of safety factors or multiple contingencies beyond the reasonable flow required to protect the pressure vessel. ... 

The ASME Pressure Vessel Code [1] and the API codes or recommended procedures [10, 13, 33] recognize and set regulations and procedures for capacity design, manufacture and installation of rupture disks, once the user has established the basis of capacity requirements. 

ASME Boiler and Pressure Vessel Committee. Recommended Guidelines for the Care of Power Boilers, 1986 edition. The American Society of Mechanical Engineers, 1986. 

Recommendations Recommended for internal inspection of pressure vessels to use in addition to UT techniques, recognizing its limitation for advanced stages of HTHA and not finding microscopic stages of HTHA. Can be used to follow-up indications from other methods or at suspected hot spots where damage is suspected. Not recommended for general HTHA detection. May be useful for verification of shear wave UT indications. Recommended for internal inspection of pressure vessels to use in addition to UT MT techniques. Additional development work and field trials recommended. Not currendy recommended as a primary method for HTHA detection. 

A mineral was being leached by heating with 7 M nitric acid in a PTFE-lined bomb heated by immersion in a silicone oil bath, and at 195°C a violent explosion occurred. This was attributed to prior leakage of oil into the pressure vessel, which had been immersed in the oil at 120°C, then allowed to cool, before being heated to the higher temperature. Appropriate precautions are recommended. 

The choice of a pressure versus atmospheric vessel for the skimmer tank is not determined solely bv watrr-treatine requirements. Overall needs of the system need to be taken into account in making this decision. Pressure vessels are more expensive However, they are recommended when ... 

Authorities responsible for national pressure vessel and piping codes recommend detailed design procedures. Furthermore a short introduction to national regulations is given. 

The shell is constructed from carbon steel and will be fabricated from standard pipe of nominal size 30, schedule number 80. The 112 tubes required are 1.83 m (6ft) lengths and standard BWG 12. The tubes are made from stainless steel type 250 as recommended in the Australian Design Code AS1548 Design of Boilers and Pressure Vessels. 

The tank dimensions are determined according to standard tank geometries as used by the Denver Company (United States). Tank shell thickness is sized according to the limitations imposed by the Australian design standard for pressure vessels (AS1 210 Ref. T1). The tank contents are non-flammable but highly toxic and corrosive, appropriate safety features are recommended. Details of the calculations are given in Appendix J. 

Ough and Amerine (8) at Davis showed that a good quality submerged flor could be produced rapidly in pressure vessels and recommended a semicontinuous process where part of the finished flor was removed periodically and replaced with new material. 

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