Tema standards for heat exchangers free download

Shell Nozzle Vent Connection Shell Cover Flange Drain Connection Expansion Joint Instrument Connection Floating Tubesheet Support Saddle Floating Head Cover Lifting Lug Floating Head Backing Device Split Shear Ring Liquid Level Connection Slip-on Backing Flange Dimensions in are millimeters.

These tolerances may be adjusted as necessary to meet the tolerances shown in Figure F-l. Protrusions above the serrations are not permitted. Baffle is a device to direct the shell side fluid across the tubes for optimum heat transfer. Baffle and Suooort Plate Tube Hole Clearance is the diametral difference between the nominal tube CD and the nominal tube hole diameter in the baffle or support plate.

DoubleTubesheet Construction is a type of construction in which two 2 spaced tubesheets or equivalent are employed in lieu of the single tubesheet at one or both ends of the heat exchanger.

Effective Shell and Tube Side Desian Pressures are the resultant load values expressed as uniform pressures used in the determination of tubesheet thickness for fixed tubesheet heat exchangers and are functions of then shell side design pressure, the tube side design pressure, the equivalent differential expansion pressure and,.. Eauivalent Boltina Pressure is the pressure equivalent resulting from the effects of bolting loads imposed on tubesheets in a fixed tubesheet heat exchanger when the tubesheets are extended for bolting as flanged connections.

Eauivalent Differential Exoansion Pressure is the pressure equivalent resulting from the effect of tubesheet loadings in a fixed tubesheet heat exchanger imposed by the restraint of differential thermal expansion between shell and tubes. Exoanded Tube Joint is the tube-to-tubesheet joint achieved by mechanical or explosive expansion of the tube into the tube hole in the tubesheet.

Flanae Load Concentration Factors are factors used to compensate for the uneven application of bolting moments due to large bolt spacing. Normal Oaeratina Conditions of a shell and tube heat exchanger are the thermal and hydraulic performance requirements generally specified for sizing the heat exchanger.

Pulsatino Fluid Conditions are conditions of flow generally characterized by rapid fluctuations in pressure and flow rate resulting from sources outside of the heat exchanger. Seismic Loadings are forces and moments resulting in induced stresses on any member of a heat exchanger due to pulse mode or complex waveform accelerations to the heat exchanger, such as those resulting from earthquakes.

Shell and Tube Mean Metal Temoeratures are the average metal temperatures through the shell and tube thicknesses integrated over the length of the heat exchanger for a given steady state operating condition.

Shut-Down Conditions are the conditions of operation which exist from the time of steady state operating ,condftions to the time that flow of both process streams has ceased. Tubesheet Liqament is the shortest distance between edge of adjacent tube holes in the tube pattern Welded Tube Joint is a tube-to-tubesheet joint where the tube is welded to the tubesheet.

Reference No. Propcwal No. Date Rev. Inem No. The manufacturer shall carry out the inspections required by the ASME Code, and also inspections required by state and local codes when the purchaser specifies the plant location. Advance notification shall be given as agreed between the manufacturer and the purchaser. Inspection by the purchaser shall not relieve the manufacturer of his responsibilities. When insulation thickness is specified by the purchaser, the name plate shall be attached to a bracket welded to the exchanger.

Such information can be noted on the name plate or on a supplemental plate attached to the exchanger at the name plate location. When a heat exchanger is registered with TEMA, a unique number is assigned to the heat exchanger. Other drawings may be furnished as agreed upon by the purchaser and the manufacturer. It is anticipated that a reasonable number of minor drawing changes may be required at that time.

Changes subsequent to receipt of approval ma cause additional expense chargeable to the purchaser. Shop detail drawings, while primarily P.

When detail drawings are requested, they will only be supplied after outline drawings have been approved. Unless otherwise agreed upon by the manufacturer and purchaser, the following paragraphs in this section will be applicable. The manufacturer shall guarantee thermal performance and mechanical design of a heat exchanger, when operated at the desi n conditions specified by the purchaser in his order, or shown on the exchanger specificatron s1 eet furnished by the manufacturer Figure G This guarantee shall extend for a period of twelve 12 months after shipping date.

The manufacturer shall assume no responsibility for excessive fouling of the apparatus by material such as coke, silt, scale, or any forergn substance that may be deposited. The thermal guarantee shall not be applrcable to exchangers where the thermal performance rating was made by the purchaser. Test conditions and procedures shall be selected by agreement between the purchaser and the manufacturer to permit extrapolation of the test results to the specified I, design conditions.

Parts fabricated to drawings furnished by the purchaser shall be guaranteed to meet the dimensions and tolerances specified. This is not to imply that the unrts must be completely dry. For purposes of support design, forces from external nozzle loadings, wind and seismic events are assumed to be negligible unless the purchaser specifically details the requirements. When these additional loads and forces are required to be considered, the combinations need not be assumed to occur simultaneously.

The references under Paragraph G Horizontal units are normally provided with at least two saddle type supports, with holes for anchor bolts. The holes in all but one of the sup arts are to be elongated to accommodate axial movement of the unit under operating con c!.

Other types of support may be used if all design criteria are met, and axial movement is accommodated. The supports may be of the lug, annular ring, leg or skirt type. If the unit is to be located in a supporting structure, the supports should be of sufficient size to allow clearance for the body flanges. Correct installation and preventive maintenance are user responsibilities. For fixed tubesheet exchangers, provide sufficient clearance at one end to permit withdrawal and replacement of the tubes, and enough space beyond the head at the opposite end to permit removal of the bonnet or channel cover.

Foundation bolts should be set to allow for setting inaccuracies. In concrete footings, pipe sleeves at least one size larger than bolt diameter slipped over the bolt and cast in place are best for this purpose, as they allow the bolt center to be adjusted after the foundation has set.

Slotted holes in suppotts are provided for this purpose. Protective plugs and covers should not be removed until just prior to installation. Under some conditions, the use of strainers in the piping may be required. Special consideration must be given to discharge of hazardous or toxic fluids, E They should not be piped to a common closed manifold. When specified by the purchaser, the manufacturer will provide the necessary connections for the safety relief devices.

The size and ty e of the required connections will be specified by the purchaser. The purchaser will prow. Local safety and health regulations must be considered. During start-up all vent valves should be opened and left open until all passages have been purged of air and are completely filled with fluid. For fixed tubesheet exchangers, flutds must be introduced in a manner to minimize differential expansion between the shell and tubes.

If it is necessary to stop the flow of cold medium, the circulation of hot medium through the exchanger should also be stopped. For fixed tubesheet exchangers, the unit must be shut down in a manner to minimize differential expansion between shell and tubes. When shumng down the system, all units should be drained completely when there is the possibility of freezing or corrosion damage.

To reduce water retention after drainage, the tube side of water cooled exchangers should be blown out with air. Hot fluid must not be sudden 7. Therefore, all external bolted joints may require retightening after installation and, if necessary, after the exchanger has reached operating temperature. Neglect in keeping all tubes clean may result in complete stoppage of flow through some tubes which could cause severe thermal strains, leaking tube joints, or structural damage to other components.

Sacrificial anodes, when provided, should be inspected to determine whether they should be cleaned or replaced.

A light sludge or scale coating on the tube greatly reduces its efficiency. The umt should first be checked for air or vapor binding to confirm that this is not the cause for the reduction in performance. Since the difficulty of cleaning increases rapidly as the scale thickness or deposit increases, the intervals between cleanings should not be excessive.

In most cases, the entire front face of each tubesheet will be accessible for inspection. The point where water escapes indicates a defective tube or tube-to-tubesheet joint. For fixed tubesheet units where tubesheets are not an integral part of the shell and for units with removable bundles, remove bonnet, re-bolt tubesheet to shell or install test flange or gland, whichever is applicable, and apply hydraulic pressure in the shell.

See Figure E Install test ring and bolt in place with gasket and packing. Apply hydraulic pressure in the shell. A typical test ring is shown in Figure E When a test ring is not available t is possible to locate leaks m the floating head end by removing the shell cover and applying hydraulic pressure in the tubes. Leaking tube joints may then be located by sighting through the tube lanes.

If the tubesheet does not have tapped holes for eyebolts, steel rods or cables inserted through tubes and attached to bearing plates may be used. The bundle should be supported on the tube baffles, supports or tubesheets to prevent damage to the tubes. Gasket and packing contact surfaces should be protected. Convenient means for cleaning should be made available. Heat exchangers may be cleaned by either chemical or mechanical methods.

The method selected must be the choice of the operator of the plant and will depend on the type of deposit and the facilities available in the plant. Following are several cleaning procedures that may be considered: 1 Circulating hot wash oil or light distillate through tubes or shell at high velocity may effectively remove sludge or similar soft deposits.

Care should be taken to ensure that tubes are not over expanded. Gaskets should be properly positioned before attempting to retighten bolts. It is recommended that when a heat exchanger is dismantled for any cause, it be reassembled with new gaskets. Composition gaskets become dried out and brittle so that they do not always provide an effective seal when reused.

Metal or metal jacketed gaskets, when compressed initially: flow to match their contact surfaces. In so doing they are work hardened and, if reused, may prowde an imperfect seal or result in deformation and damage to the gasket contact surfaces of the exchanger.

Bolted joints and flanges are designed for use with the particular type of gasket specified. Substitution of a gasket of different construction or improper dimensions may result in leakage and damage to gasket surfaces. Therefore, any gasket substitutions should be of compatible design. Any leakage at a gasketed joint should be rectified and not permitted to persist as it may result in damage to the gasket surfaces. Metal jacketed type gaskets are widely used.

When these are used with a tongue and groove joint without a nubbin, the gasket should be installed so that the tongue bears on the seamless side of the gasket jacket. When a nubbin is used, the nubbin should bear on the seamless side. Replacement parts should be purchased from the original manufacturer. Defective tubes may be plugged using commercially available tapered plugs with ferrules or tapered only plugs which may or may not be seal welded. Criteria contained in these Standards may be applied to units which exceed the above parameters.

These Standards supplement and define the Code for heat exchanger applications. The manufacturer shall comply with the construction requirements of state and local codes when the purchaser specifies the plant location. It shall be the responsibility of the purchaser to inform the manufacturer of any applicable local codes. Application of the Code symbol is required, unless otherwise specified by the purchaser.

Materials of construction, including gaskets, should be specified by the purchaser. The manufacturer assumes no responsibility for deterioration of parts for any reason.

The test pressure shall be held for at least 30 minutes. The shell side and the tube side are to be tested separately in such a manner that leaks at the tube joints can be detected from at least one side.

When the tube side design pressure is the higher pressure, the tube bundle shall be tested outside of the shell only if specified by the purchaser and the construction permits. It must be recognized that air or gas is hazardous when used as a pressure testing medium.

The pneumatic test pressure at room temperature shall A be in accordance with the Code. The test pressure shall be as agreedy upon by the purchaser and manufacturer, but shall not exceed that required by Paragraph RCB The Code provides the allowable stress limits for parts to g e deslgned at the specified design temperature. The design metal temperature shall be based on the operating temperatures of the shellside and the tubeside fluids, except when the purchaser specffies some other design metal temperature.

When the design metal tern erature is less than the higher of the design temperatures referred to in Paragraph RCfir It is used to establish metal properties under operating conditions. The mean metal temperature is based on the specified operating temperatures of the fluid in contact with the part. The mean metal temperature is based on the specified operating temperatures of the shellside and tubeside fluids.

In establishing the mean metal temperatures, due consideration shall be given to such factors as the relative heat transfer coefficients of the two fluids contacting the part and the relative heat transfer area of the parts contacted by the two fluids.

Corrosion allowance on the outside of the d flanged portion may be included in the recommended minimum edge distance. Q 6 :, ,,,:. Q RCB Pass partition plates are not required to have corrosion allowance. Cast iron shall not be used for pressures exceeding I50 psi kPa , or for lethal or flammable fluids at any pressure.

If a heat exchanger is to be furnished with anodes, when requesting a quotation, the purchaser is responsible for furnishing the heat exchanger manufacturer the following information: 1 Method of anode attachment. If the heat exchanger manufacturer chooses to install anodes for a customer, the manufacturer is not responsible for the suitability of the anodes for the service it is installed in, the life of the anodes, the corrosion protection provided by the anode, or any subsequent damage to the heat exchanger attributed to the anode, the method of anode installation, or the installed location of the anode in the heat exchanger.

Other lengths may be used. Also see Paragraph N-l. Other diameters and gages are acceptable. Characteristics of tubing are shown in Tables D-7 and D7M. Specified wall shall be based on the thickness at the root diameter. U-bends formed from tube materials having low ductility, or materials which are susceptible to work-hardening, may require special consideration.

Also refer to Paragraph RCB Metal-to-metal contact between bends in the same plane shall not be permitted. Heat treatment to alleviate such conditions may be performed by agreement between manufacturer and purchaser.

The nominal total thickness for clad shells shall be the same as for carbon steel shells. Other type baffles are permissible. Baffle cut is defined as the segment opening height expressed as a ercentage of the shell inside diameter or as a percentage of the total net free area inside the shell Pshell cross sectional area minus total tube area.

The number of tube rows that overlap for multi-segmental baffles should be adjusted to give approximately the same net free area flow through each baffle. Baffles shall be cut near the centerline of a row of tubes, of a pass lane, of a tube lane, or outside the tube pattern.

Baffles shall have a workmanlike finish on the outside diameter. Typical baffle cuts are illustrated in Figure RCB Baffle cuts may be vertical, horizontal or rotated. For pulsating conditions, tube holes may be smaller than standard. Any burrs shall be removed and the tube holes given a workmanlike finish.

Baffle holes will have an over-tolerance of 0. However, where such clearance has no significant effect on shell side heat transfer coefficient or mean temperature difference. See Paragraph RCS The design inside diameter of a plate shell is the specified inside diameter.

In any case, the design inside diameter may be taken as the actual measured shell inside diameter. The thickness of the baffle or support plates fo r U-tube bundles shall be based on the unsupported tube length in the straight section of the bundle. The U-bend length shall not be constdered in determining the unsupported tube length for required plate thickness. End spaces between Nominal Shell ID tubesheets and baffles are not a consideration.

However, special design considerations may dictate a closer spacing. Refer to Section 6for vibration criteria. When this is not possible, the baffles nearest the ends of the shell, and or tubesheets, shall be located as close as practical to the shell nozzles. The remaining badles normally shall be spaced uniformly.

Where bend diameters prevent compliance, special provisions in addition to the above shall be made for support of the bends. If the span under these circumstances approaches the maximum permitted by Paragraph RCE Existing predictive correlations are inadequate to insure that any given design will be free of such damage. In any case, and consistent with Paragraph G-5, the manufacturer is not responsible or liable for any direct, indirect, or consequential damages resulting from vibration.

These limitations have no correlation to tube vibration and the designer should refer to Section 6 for information regarding this phenomenon. For all other gases and vapors, including all nominally saturated vapors, and for liquid vapor mixtures, impingement protection is required.

A properly designed diffuser may be used to reduce line velocities at shell entrance. Any baffte segment requires a minimum of three points of support. Any baffle segment requires a minimum of three points of support. Sealing devices may be seal strips, tre rods wrth spacers, dummy tubes, or combinations of these.

One method is shown in Figure R CpB Other methods which satisfy the intent are acceptable. Bundle hold-downs are not required for fixed tubesheet kettles. For single pass floating head covers the depth at nozzle centerline shall be a minimum of one-third the inside diameter of the nozzle. Other styles are permissible. If a plate is used, the thickness shall equal or exceed the support plate thickness specified in Table R If packing of braided material is used, a minimum of three rings of packing shall be used for PSI kPa maximum design pressure and a minimum of four rings shall be used for PSI kPa maximum design pressure.

Figure RCB When the skirt must extend inward, a suitable method shall be used to prevent stagnant areas between the shell side nozzle and the tubesheet. Design temperature, pressure and shell diameter shall be limited by the service, joint configuration, packing material and number of packing rings, to a maximum design pressure of psi kPa.

When endless packing rings are used, one ring of packing shall be used on each side of the lantern ring. For braided packing materials with a seam, a minimum of two rings of packing shall be used on each side of the lantern ring, with the seams staggered during assembly. Provisions for leak detection shall be considered.

This shall not exclude gaskets made continuous by welding or other methods which produce a homogeneous c bond. When two gasketed joints are corn ressed by the same bolting, provisions shall be made so that both gaskets seal, but neither gas Ret is crushed at the c; required bolt load. Metal jacketed, 0 filled or solid metal gaskets shall be used for all joints for design pressures greater than psi fi kPa and for internal floating head joints.

Other gasket materials may be specified by agreement between purchaser and manufacturer to meet special service conditions and flange design. When Q two gasketed joints are compressed by the same bolting, provisions shall be made so that both gaskets seat, but neither gasket is crushed at the required bolt load.

Q B Full face gaskets shall be used for all cast Iron flanges. This maximum deviation shall not occur in less 0 than a 20 o 0. Both tubesheets of fixed tubesheet exchangers shall have the same thickness, unless the provisions of Paragraph RCB See Paragraph RCB For floating tubesheets Type T , where the tubesheet is extended for bolting to heads with ring type gaskets, the effect of the moment acting upon the extension is defined in Paragraph RCB For fixed tubesheet exchangers, G shall be the shell inside diameter.

For kettle type exchangers, G shall be the port inside diameter. For any floating tubesheet except divided , Gshall be the Gused for the stationary tubesheet using the Pas defined for other type exchangers. For other type exchangers, G shall be the diameter, inches mm , over which the pressure under consideration is acting. Competing software imports only a small part of the HTRI design file. Are you looking for a way to quickly create heat exchanger drawings? A copy of the licensing agreement accompanies the software.

Tubular Exchanger Manufacturers Association, Inc. The 9th Edition retains the useful data and features found in the Eighth Edition plus many clarifications and innovations. Some noteworthy features of the Ninth Edition include:. New rules for flexible shell elements expansion joints , which are based on a Finite Element Analysis FEA approach Tables for tube hole drilling have been expanded to 3 diameter tubes Guidelines for performing Finite Element Analysis FEA had been added.

Rules for the design of shell intersections with large nozzle to cylinder ratios subjected to pressure and external loadings have been added Foreign material cross-reference linking material specifications from various international codes has been added Rules for the design of longitudinal baffles have been added.

Programs now have a typical Windows toolbar and user-friendly input forms. To browse Academia. Printed in the United States of America.

ALCO Products. The 9th Edition retains the useful data and features found in the Eighth Edition plus many clarifications and innovations. Tables for tube hole drilling have been expanded to 3 diameter tubes Guidelines for performing Finite Element Analysis FEA had been added.

Tubular Exchanger Manufacturers Association, Inc. A copy of the licensing agreement accompanies the software. Industrial Heat Exchangers www.

TEMA standards provide a recognized approach to end users and allow comparison between competitive designs for a given application. TEMA R: Unfired shell and tube heat exchangers for the generally severe requirements of petroleum and related processing applications. TEMA C: Unfired shell and tube heat exchangers for the generally moderate requirements of commercial and general process applications. TEMA C generally specified in more typical shell and tube heat exchanger applications that do not require the severe requirements of chemical or petroleum processing service.