## Design Of Pipe Coils For Heat Transfer [1018

This procedure is specifically for helical pipe coils in vessels and tanks. Other designs are shown for illustrative purposes only. Helical coils are generally used where large areas for rapid heating or cooling are required. Heating coils are generally placed low in the tank cooling coils are placed high or uniformly distributed through the vertical height. Here are some advantages of helical pipe coils. 1. Lower cost than a separate outside heat exchanger. .'3. Fluids circulate at higher...

## 12

Cross-bracing the legs will conveniently reduce bending in legs due to overturning moments (wind and equipment) normally associated with unbraced legs. The lateral bracing of the legs must be sized to take lateral loads induced in the frame that would otherwise cause the legs to bend. 2. Legs may be made from angles, pipes, channels, beam 3. Legs longer than about 7 ft should be cross-braced. 4. Check to see if the cross-bracing interferes with piping from bottom head. 5. Shell stresses at the...

## 215216

Reinforcement at small end with internal pressure, 213-214 Cone lifting lugs, 416-419 Cones, formula, 16 Corrosion fatigue, 5 stress, 5 Creep deformation, 5 Critical force, 85 Critical length, 85 Critical load, 85 Critical stress, 85 Critical wind velocity, 244, 246, 249 See also Cone-cvlinder intersections calculating proportions, 92 Cylindrical shells. 11 buckling of thin-walled, 85-89 external pressure design for, 20 formulas, 15, 88 Cylindrical shells, stress in bending moment, 278, 280,...

## Trial

If in. < t < in., use Type 2. If t > in., use Type 3 or 4. 2. To reduce sizes of anchor bolts Increase number of anchor bolts. Increase width of base plate. 3. Number of anchor bolts should always be a multiple of 4. If more anchor bolts are required than spacing allows, the skirt may be angled to provide a larger bolt circle or bolts may be used inside and outside of the skirt. Arc spacing should be kept to a minimum if possible. 4. The base plate is not made...

## 2

Both ASME Code, Section VIII, Division 2 and ASME Code, Section III, utilize the maximum shear stress criterion. This theory closely approximates experimental results and is also easy to use. This theory also applies to triaxial states of stress. In a triaxial stress state, this theory predicts that yielding will occur whenever one-half the algebraic difference between the maximum and minimum stress is equal to one-half the yield stress. Where al > a2 > the maximum shear stress is (cti ct3)...

## 31875

Note 3 4 and 7 8in. bolts are UNC series threads. All others are 8 series threads. All dimensions are from ANSI B 18.2. Note 3 4 and 7 8in. bolts are UNC series threads. All others are 8 series threads. All dimensions are from ANSI B 18.2. Modulus of Elasticity, E& , 10 psi

## 4b

Step 8 If the computed allowable external pressure is less than the design external pressure, then a decision must be made on how to proceed. Either (a) select a new thickness and start the procedure from the beginning or (b) elect to use stiffening rings to reduce the L dimension. If stiffening rings are to be utilized, then proceed with the following steps. Step 9 Select a stiffener spacing based on the maximum length of unstiffened shell (see Table 2-la). The stiffener spacing can vary up to...

## Wind Design Per Asce [1

Projected area, sq ft force coefficient, shape factor 0.7 to 0.9 vessel effective diameter, from Table 3-4 fundamental natural frequency, 1 T, cycles per second, Hz design wind force, lb 3.5 for vessels gust effect factor, Cat A and B 0.8, Cat C and D 0.85 gust response factor for flexible vessels height of vessel, ft importance factor, see Table 3-1 the intensity of turbulence at height z velocity pressure exposure coefficient from Table 3-3a, dimensionless topographic factor, use 1.0 unless...

## Notation

A factor A for external pressure As shear area, in. B - allowable compressive stress, psi F load on weld(s), lb in. r shear stress, psi E joint efficiency E modulus of elasticity at temperature, psi S - code allowable stress, psi Hp hydrostatic end force, lb Pi maximum differential pressure on concave side of head, psi Pe maximum differential pressure on convex side of head, psi K spherical radius factor (see Table 2-2) L inside radius of hemi-head, in. 0.9D for 2 1 S.E. heads, in. KD for...

## Info

This procedure calculates the static deflection of tall towers due to various loadings and accounts for the following a. Different wind pressures at different elevations. b. Various thicknesses, diameters, and moments of inertia at different elevations. c. Different moduli of elasticity at different elevations due to a change in material or temperatures. 2. This procedure is not valid for vessels that are subject to wind-induced oscillations or that must be designed dynamically. See Procedure...

## 58

Platform .steel weight. This includes grating or floor plate, structural framing, supports, toe angle or plate, and handrailing. To find weight of steel, multiply area of platforms bv 30psf. 0 > erating Approximately 25-30 psf. Live load is small because it is assumed there are not a lot of people or equipment on the platform while vessel is operating. Combine effects with shell stress due to design pressure. Maintenance comtniction 50-75psf. Live load is large because there...

## Typical Side

Table 7-4 is based on an allowable stress of 13.7 ksi 2. Design each lug for a 2 1 safety factor. 3. Design each lug for a minimum 10 side force. Tailing load, T. WL cos 6 L2 cos 6 Lj + sin 6 L4 At 0 0, initial pick point, vessel horizontal T - and P -- or r Wl T Calculate the loads for various lift angles, 9.

## 109

Cone-cylinder intersections are areas of high discontinuity stresses. For this reason the ASME Code requires reinforcement at each junction and limits angle a to 30 unless a special discontinuity analysis is performed. This procedure enables the designer to take into account combinations of loads, pressures, temperatures, and materials for cones where a is less than or equal to 30 without performing a discontinuity analysis and fulfill all code requirements. 2. The design may be checked...

## Calculations

MAWP, corroded at Design Temperature Pw. Shell Rc + 0.6tsc R0 - 0.4tst. 2 1 S.E. Head 2SDTEtiu. 2SDTEtht. Pw - or 2SaEthn 2SaEt Pm - r or For clad vessels where credit is taken for the clad material, the following thicknesses may be substituted into the equations for MAP and MAWP

## Gasket Facing and Selection

The gasket facing and type correspond to the service conditions. fluid or gas handled, pressure, temperature, thermal shock, cyclic operation, and the gasket selection. The greater the hazard, the more care that should be invested in the decisions regarding gasket selection and facing details. Facings which confine the gasket, male and female, tongue and groove and ring joint offer greater security against blowouts. Male and female and tongue and groove have the disadvantage that mating flanges...

## 083

Reprinted by permission of the Welding Research Council. Reprinted by permission of the Welding Research Council. Reprinted by permission of the Welding Research Council. Analysis When Reinforcing Pads Are Used Figure 3-37. Dimensions of load areas for radial loads. Figure 3-37. Dimensions of load areas for radial loads.

## 01849

'Values of 1.43 log1oR r + 0.11 (r R)2 2Values of 1.43 log,0R r +0.334+ 0.06(r R)2 Values of 1.365 (3n + 2ni + 3) 6Values of 50 (3n + 2n2 + 12.5) Reprinted by permission of AISI, Committee of Steel Plate Producers and Steel Plate Fabricators Association, Inc. from Steel Plate Engineering Data, Volume 2 'Values of 1.43 log1oR r + 0.11 (r R)2 2Values of 1.43 log,0R r +0.334+ 0.06(r R)2 Values of 1.365 (3n + 2ni + 3) 6Values of 50 (3n + 2n2 + 12.5) Reprinted by permission of AISI, Committee of...

## Transportation And Erection Of Pressure Vessels 365

Procedure 7-1 Transportation of Pressure Vessels, 365 Procedure 7-2 Erection of Pressure Vessels, 387 Procedure 7-3 Lifting Attachments and Terminology, 391 Procedure 7-4 Lifting Loads and Forces, 400 Procedure 7-5 Design of Tail Beams, Lugs, and Base Ring Details, 406 Procedure 7-6 Design of Top Head and Cone Lifting Lugs, 416 Procedure 7-7 Design of Flange Lugs, 420 Procedure 7-8 Design of Trunnions, 431 Procedure 7-9 Local Loads in Shell Due to Erection Forces, 434 Procedure 7-10...

## 5

Although this refinement is an improvement, it still does not factor in all of the variables. But before describing the actual procedure, a brief description of the sizing of drums in general is warranted. Here are some typical types of drums Typically the sizing of drums is related to a process consideration such as liquid holdup (surge), storage volume, or velocity considerations for separation. Surge volume in process units relates to the response time required for the alarms and operators...

## Notes

Make sure to remain consistent by lug, that is, that all loadings are from the same lug. This may require several trials to determine the worst case. 2. The calculations for combining stresses with a reinforcing pad should be completed for stresses at the edge of attachment as well as at the edge of the pad. For thinner shells the stress at the edge of the pad will usually govern. 1. A change in location of the e.g. for various operating levels can greatly affect the moment at lugs by...

## 1

F dead load-)-live load, psf fb bending stress, beam, psi fa axial stress, psi fx.v.r bolt loads, lb F total load on bracket, lb A load area, ft2 A' cross-sectional area of kneebrace, in.2 Mi moment at shell, ft-lb M2 moment at bolts, ft-lb or in.-lb C distance to C.G. of area, ft K end connection coefficient, use 1.0 r' radius of gyration, in. P axial load on kneebrace, lb Z section modulus of beam, in.3

## C

Carbon steel plate, weights of, 97 Center of gravity, finding or revising, 80 Choker (cinch) lift at base, 413 Circular platforms bracket spacing, 303 dead loads, 303 dimensions, 296-297 Circular platforms (Continued) formulas, 297 kneebrace design, 298, 303 live loads, 300-301, 303 moment at shell graph, 299 notation, 296 Circular rings, stress in allowable stress, 258 coefficient graphs, 264 coefficient values, 260-263 moment diagrams, 256 moments and forces, determining, 259-265 notation,...

## General Design

Procedure 2-1 General Vessel Formulas, 15 Procedure 2-2 External Pressure Design, 19 Procedure 2-3 Calculate MAP, MAWP, and Test Pressures, 28 Procedure 2-4 Stresses in Heads Due to Internal Pressure, 30 Procedure 2-5 Design of Intermediate Heads, 31 Procedure 2-6 Design of Toriconical Transitions, 33 Procedure 2-7 Design of Flanges, 37 Procedure 2-8 Design of Spherically Dished Covers, 57 Procedure 2-9 Design of Blind Flanges with Openings, 58 Procedure 2-10 Bolt Torque Required lor Sealing...

## R

The ASME Code does not give specific procedures for designing vessels for wind. However, Para. UG-22, Loadings, does list wind as one of the loadings that must be considered. In addition, local, state, or other governmental jurisdictions will require some form of analysis to account for wind loadings. Client specifications and standards also frequently require consideration of wind. There are two main, nationally recognized standards that are most frequently used for wind design. They are 1....

## N

Transverse load This method of determining uplift and overturning is determined from Ref. 21 (see Figure 3-57). If e < f then there is no uplift. If e > , then proceed with the following steps. This is an iterative procedure for finding the tension force, T, in the outermost bolt. Step 1 Find the effective bearing length, Y. Start by calculating factors K

## 05

The tailing lug is designed like all other lugs. The forces are determined from the tailing load. T, calculated per this procedure. The ideal position lor the tailing lug is to be as close as possible to the base plate for stiffness and transmitting these loads through the base to the skirt. The option of using a tailing lug versus a tailing beam is the designer's choice. Either can accommodate internal skirt rings, stiffeners. and struts. Area required at pin hole, A,-. T Area available at pin...

## A

Agitation, defined, 328 Agitators, helical pipe coils with, 341 AISC Steel Construction Manual 109, 110 Anchor bolts, base details and equivalent area method, 195-196 force, 201 number of, 194, 200 Anchoring of saddle supports, 111 Anchor-type impellers, 329, 332 Angle oc, calculating, 34 ASCE, wind design per, 112-117 ASME (American Society of Mechanical Engineers) Division 1 versus Division 2, 7 Section VIII, Division 1, 443-444 STS-1 method, 251 Attachments, converting, 267-269 AWWA D-100,...

## 015

Membrane force due to Pr. (Extracts from BS 5500 1985 are reproduced by permission of British Standards Institution, 2 Park Street London, W1A 2BS, England. Complete copies can be obtained from national standards bodies.) Figure 5-26. Bending moment due to Pr. (Extracts from BS 5500 1985 are reproduced by permission of the British Standards Institution, 2 Park Figure 5-26. Bending moment due to Pr. (Extracts from BS 5500 1985 are reproduced by permission of the British Standards...

## Buckling Of Thinwalled Cylindrical Shells

This procedure is to determine the maximum allowable stress for tubular members that are subject to axial compression loadings. Tubular members may be a pressure vessel, a pipe, a silo, a stack, or any axially loaded cylinder of any kind. In addition, axial-loaded cylinders may be subjected to other load cases simultaneously. Other load cases include bending and internal or external pressure. Axial loads can also result when a vertical vessel, stack, or silo is transported and erected from the...

## Vessel Nomenclature

Drums and miscellaneous vessels Any of the above listed vessels can be field fabricated however, normally only those vessels that are too large to transport in one piece are field fabricated. Although it is significantly more expensive to field fabricate a vessel, the total installed cost may be cheaper than a shop fab that is erected in a single piece due to the cost of transportation and erection. There are always portions of field fab vessels that are shop fabricated. These can be as small...

## Transportation Of Pressure Vessels

The transportation of a pressure vessel by ship, barge, road, or rail will subject the vessel to one-time-only stresses that can bend or permanently deform the vessel if it is not adequately supported or tied down in the right locations. The shipping forces must be accounted for to ensure that the vessel arrives at its destination without damage. It is very frustrating for all the parties involved to have a load damaged in transit and to have to return it to the factory for repairs. The cost...

## 13

S., Design of Radial Nozzles in Cylindrical Shells for Internal Pressure, Journal of Pressure Vessel Technology, Vol. 2, February 1980. ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, American Society of Mechanical Engineers, 1995. Catudal, F. W., and Schneider, R. W., Stresses in Pressure Vessels with Circumferential Ring Stiffeners, Welding Journal Research Supplement, 1957. Wolosewick, F. E., Supports for Vertical Pressure Vessels, Part III,...

## Ws

If W LDf < 20, a vibration analysis must be performed. If 20 < W LD2 < 25, a vibration analysis should be performed. If VY' LD* > 25, a vibration analysis need not be performed. If W5 LD 2 < 0.75, the vessel is unstable. If 0.75 < W5 LD 2 < 0.95, the vessel is probably unstable. If WS LDf > 0.95, the structure is stable. Step 3 If ft < 0.95, check critical wind velocity, Vc. If Vt. > V, then instability is expected. Step 4 Calculate dynamic deflection, A, . (2.43)(109)L5Vi2...

## 007

Soft soils Bp< 1500psi, pF 0.07. 2. Medium soils, 1500 psi < BP< 3000 psi, ft 0.03. 3. Pile foundation, rock, or stiff soils, pF 0.005. 1. Soft soils Bp< 1500psi, pF 0.07. 2. Medium soils, 1500 psi < BP< 3000 psi, ft 0.03. 3. Pile foundation, rock, or stiff soils, pF 0.005.

## Membrane Stress Analysis

Pressure vessels commonly have the form of spheres, cylinders, cones, ellipsoids, tori, or composites of these. When the thickness is small in comparison with other dimensions (Rm t > 10), vessels are referred to as membranes and the associated stresses resulting from the contained pressure are called membrane stresses. These membrane stresses are average tension or compression stresses. They are assumed to be uniform across the vessel wall and act tangentially to its surface. The membrane or...

## 39

'Methods are as follows, based on graphs Method 1 K. Abakians, Hydrocarbon Processing, June 1963. Method 2 S.P. Jawadekar, Chemical Engineering, Dec. 15,1980. 'Methods are as follows, based on graphs Method 1 K. Abakians, Hydrocarbon Processing, June 1963. Method 2 S.P. Jawadekar, Chemical Engineering, Dec. 15,1980. C, corrosion allowance S, allowable stress E, joint efficiency 2. From Fig. 2-58, using F1 and vessel volume, V, determine the vessel diameter, D. 3. Use D and V to calculate the...

## Thick Walled Pressure Vessels

As discussed previously, the equations used for design of thin-walled vessels are inadequate for design or prediction of failure of thick-walled vessels where Rin t < 10. There are many types of vessels in the thick-walled vessel category as outlined in the following, but for purposes of discussion here only the monobloc type will be discussed. Design of thick-wall vessels or cylinders is beyond the scope of this book, but it is hoped that through the following discussion some insight will be...

## Design Of Vessel Supports 109

Procedure 3-1 Wind Design per ASCE, 112 Procedure 3-2 Wind Design per UBC-97, 118 Procedure 3-3 Seismic Design for Vessels, 120 Procedure 3-4 Seismic Design Vessel on Unbraced Legs, 125 Procedure 3-5 Seismic Design Vessel on Braced Legs, 132 Procedure 3-6 Seismic Design Vessel on Rings, 140 Procedure 3-7 Seismic Design Vessel on Lugs 1, 145 Procedure 3-8 Seismic Design Vessel on Lugs 2, 151 Procedure 3-9 Seismic Design Vessel on Skirt, 157 Procedure 3-10 Design of Horizontal Vessel on Saddles,...

## Nozzle Reinforcement

The following are only guidelines based on Section VIII, Division 1 of the ASME Code 1 . This is not an attempt to cover every possibility nor is it to become a substitute for a. No reinforcement other than that inherent in the construction is required for nozzles 1, Section UG-36(c) (3) 3-in. pipe size and smaller in vessel walls 3 8-in. and less. 2-in. pipe size and smaller in vessel walls greater than 3 8 in. b. Normal reinforcement methods apply to 1, Section UG-36(b) (1) Vessels 60-in....

## Design Of Bins And Elevated Tanks [39

The definition of a bulk storage container can be quite subjective. The terms bunkers, hoppers, and bins are commonly used. This procedure is written specifically for cylindrical containers of liquid or bulk material with or without small internal pressures. There is no set of standards that primarily applies to bins and since they are rarely designed for pressures greater than 15 psi, they do not require code stamps. They can, however, be designed, constructed, and inspected in accordance with...

## Minimum Design Metal Temperature Mdmt

Ri ratio of thickness required at MDMT to the corroded thickness Ro ratio of the actual stress to the allowable stress tMT thickness required of the part at MDMT, in. tDT thickness required of the part at design temperature, in. t thickness of the part, new, in (exclusive of thinning allowance for heads and undertolerance for pipe) tt. thickness of the part, corroded, in. C.a. corrosion allowance, in. E joint efficiency Smt allowable stress at MDMT, psi S)yr allowable stress at design...

## Pressure Vesels In Civil Engineering

Ladder and platform (L& P) estimating, 105 Large-diameter nozzle openings, 203-207 I D ratio, 89-90 Legs, erection of vessels with, 394 Legs, seismic design for braced calculations, 135-136 dimensional data, 133 flow chart for, 138 legs and cross-bracing, sizes for, 137 load diagrams, 134 loads, summary of, 136 notation, 132 Legs, seismic design for unbraced calculations, 127-129 Legs, seismic design for unbraced (Continued) dimensional data, 126 leg configurations, 126 leg sizing chart, 131...

## Erection Of Pressure Vessels

The designer of pressure vessels and similar equipment will ultimately become involved in the movement, transportation, and erection of that equipment. The degree of that involvement will vary due to the separation of duties and responsibilities of the parties concerned. It is prudent, however, for the designer to plan for the eventuality of these events and to integrate these activities into the original design. If this planning is done properlv, there is seldom a problem when the equipment...

## Seismic Designvessel On Skirt [1 2

T period of vibration, sec S i code allowable stress, tension, psi H overall height of vessel from bottom of base plate, ft hx height from base to center of section or e.g. of a concentrated load, ft h, height from base to plane under consideration, ft of, fi, y coefficients from Table 3-20 for given plane based on hx H Wx total weight of section, kips W weight of concentrated load or mass, kips W total weight of vessel, operating, kips W), total weight of vessel above the plane under...

## Vibration Of Tall Towers And Stacks [1727

Tall cylindrical stacks and towers may be susceptible to wind-induced oscillations as a result of vortex shedding. This phenomenon, often referred to as dynamic instability, has resulted in severe oscillations, excessive deflections, structural damage, and even failure. Once it has been determined that a vessel is dynamically unstable, either the vessel must be redesigned to withstand the effects of wind-induced oscillations or external spoilers must be added to ensure that vortex shedding does...

## Type 1 Butt Weld Uw

For shackles with safe loads greater than the maximum shown, use Crosby-Laughlln The Crosby Group, Div. of American Hoist amp Derrick Co, Tulsa, OK 74101 . Skookum Skookum Co., Inc., Portland, OR 97203 , or equal with an ultimate strength at least 5 times the safe working load. For shackles with safe loads greater than the maximum shown, use Crosby-Laughlln The Crosby Group, Div. of American Hoist amp Derrick Co, Tulsa, OK 74101 . Skookum Skookum Co., Inc., Portland, OR 97203 , or equal with an...

## Allowable Buckling Stress In Cylindrical Shells [1420

A metal cross-sectional area, in.2 B ASME Code allowable stress, psi C end connection coefficient, use 1.0 for simply supported and 2.0 for cantilevered Cc. max allowable slenderness ration per AWYVA D-100 D OD of cylinder, in. E modulus of elasticity, psi e tolerance for peaking, in. FS factor of safety Fv minimum specified yield strength, psi F , allowable longitudinal compressive stress, psi 1 moment in inertia, in.4 Lc length at which critical stress is achieved, in. 1 tolerance for...

## Seismic Designvessel On Unbraced Legs [47

A cross-sectional area, leg, in.2 V base shear, lb W operating weight, lb n number of legs Cv vertical seismic factor Ch - horizontal seismic factor y static deflection, in. Fv vertical seismic force, lb F , horizontal seismic factor, see Procedure 3-3 F l allowable axial stress, psi F , allowable bending stress, psi F, - seismic force applied at top of vessel, lb F'. Euler stress divided by safety factor, psi fi maximum eccentric load, lb V horizontal load on leg, lb Fn maximum axial load, lb...

## Design Of Base Details For Vertical Vessels

E modulus of elasticity at design temperature, psi Ab cross-sectional area of bolts, in.2 d diameter of bolt circle, in. VVb weight of vessel at base, lb WT weight of vessel at tangent line, lb w width of base plate, in. S code allowable stress, tension, psi N number of anchor bolts allowable bearing pressure, concrete, psi Fv minimum specified yield stress, skirt, psi Fs allowable stress, anchor bolts, psi fLT axial load, tension, lb in.-circumference fix axial load, compression, lb...

## External Pressure Chart

If a vessel is designed for less than 15 psi, and the external pressure condition is not going to be stamped on the nameplate, the vessel does not have to be designed for the external pressure condition. Figure 2-1 b. External pressure cones 22 112 lt a lt 60 . For Case B, L . L For Cases A, C, D, E Figure 2-1e. Geometrie chart for components under external or compressive loadings for all materials . Reprinted by permission from the ASME Code. Section VIII, Div. 1. Figure 2-1e. Geometrie chart...

## References

Magnusson, I., Design of Davits, Fluor Engineers, Inc., Irvine, Ca. 2. Roark, R. J., Formulas for Stress and Strain, 3rd edition, McGraw-Hill Book Co., 1954, Article 44, p 146. 3. Naberhaus, E. Paul, Structural Design of Bins, Chemical Engineering, February 15, 1965, pp. 183-186. 4. Lambert, F. W., The Theory and Practical Design of Bunkers, British Constructional Steelwork Association, Ltd., London. 5. API-620, Recommended Rules for Design and Construction of Large, Welded, Low-Pressure...

## Discontinuity Stresses

Vessel sections of different thickness, material, diameter, and change in directions would all have different displacements if allowed to expand freely. However, since they are connected in a continuous structure, they must deflect and rotate together. The stresses in the respective parts at or near the juncture are called discontinuity stresses. Discontinuity stresses are necessary to satisfy compatibility of deformation in the region. They are local in extent but can be of very high...