Floating head exchangers are used when the media being handled causes fairly rapid fouling. Heat transfer equipment may be designated by type or function it performs, such as chiller, condenser, cooler reboiler, etc. The hard coke fragments can originate in the reactor overhead line or in the main fractionator and often become dislodged following a unit shutdown. Floating head type shell and tube heat exchanger so as to make removal of the tube bundles possible and to allow for considerable expansion of the tubes, a floating head exchanger is used. Other important heat exchanger components include those in the floating head assemblies, supports and rectangular headers in air cooled exchangers.
Tubes can expand freely, the channel head and shell cover arrangement are convenient for inspection, and the tube bundle can be removed easily for cleaning. In this, exchanger tubes are fixed at both the ends of the floating and stationary tubes sheet. Part i, analysis, design and inspection, 363373, asme, new york. As shown in the name of it, in this design, one end of the tubesheet is fixed to the shell, while the other one can float freely inside the shell. Third party inspection for shell and tube heat exchanger mockup test of tube to tubesheet weld. With high reliability and wide adaptability, floating head heat exchanger has accumulated a wealth of experience during the long term using process, and promoted its. Feb 23, 2000 this comprehensive reference covers all the important aspects of heat exchangers hestheir design and modes of operationand practical, largescale applications in process, power, petroleum, transport, air conditioning, refrigeration, cryogenics, heat recovery, energy, and other industries. Inspection of the entire length of heat exchanger tubes however brings along a few extra challenges. Look for floating flames, flame roll out or flame distortion. Head off heat exchanger errors chemical processing.
Feb 26, 2015 14 floating head heat exchanger pg check bundle to shell gasket sealing check back cover gasket sealing fill shell side by water drain floating head heat exchanger shell side final hydrotest. The coke fragments generally accumulate on the exchanger tube sheets at the inlet to the tubes resulting in an excessive pressure drop and loss of heat transfer duty. If no flame disturbances are observed, proceed to step 2. Inspection and test plan for shell and tube heat exchanger important points. These are commonly used up to temperature difference of 9095 c. The documentation book furnace heat exchanger failure.
This type of exchangers consists of tubes which are bent in the form of a u. Split ring type heat exchanger floating head joint leak. Heat exchanger heat exchanger evaporative condenser receiver compressors compressors brine supply receiver. The floating tube heat exchanger is unlike any shell and tube heat exchanger. In floating head type heat exchanger, fluid runs through the tubes and another fluid flows over the tubes which transfer the heat between these two fluids. Floating head heat exchanger design tema api anson. On a floating head, the secondary tubesheet is small enough to pass through. Removable bundle, outside packed floating head designs such as this type bep allow easy tube bundle removal and inspection and cleaning of the shell circuit and shell interior. The invention discloses an assembly for a pressure test of a floating head type heat exchanger. Fixed tube sheet heat exchanger chemical engineering world. An example of hard coke fouling is solid coke fragments circulating through the slurry exchanger tubes and restricting flow through the exchanger.
The assembly comprises a doublecylinder assembly which is connected with a side flange on a shell of a floating head. A practical guide for planning, selecting and designing of shell and tube exchangers takes users on a stepbystep guide to the design of heat exchangers in daily practice, showing how to determine the effective driving temperature difference for. A pullthrough floating head exchanger with an integral shell cover may be. A floating head is excellent for applications where the difference in temperature between the hot and cold fluid causes unacceptable stresses in the axial direction of the shell and tubes. This standard specifies the floating head heat exchanger including heat exchanger and condenser with external bonnet side flange hereinafter referred to as side flange structure type and family size. Inspection and test plan for shell and tube heat exchanger. Fixed tubesheet exchangers, utube exchangers, floating head exchangers. Continuation details install back cover with gasket water pump raise the pressure up to value given by inspection discharge the water, remove pg and. Mar 05, 2020 floating head is fitted to the tube sheet which is away from the channel. Reflecting the authors extensive practical experienc.
Floating tube sheet diameter is kept slightly smaller than the inner shell diameter so that the entire tube bundle can be removed from the channel end. The planning process starts by finding out what data is needed from the inspection. Two fluids can exchange heat, one fluid flows over the outside of the tubes while the. The authors have presented more than 100 short intensive courses on shellandtube heat exchangers, closed feed water heaters, and tubular exchanger inspection, maintenance, and repair in the united states, canada, and europe. Heat transfer by shell and tube heat exchangers tema. It is specially designed to be completely stressfree to promote longer equipment life and virtually no maintenance. The coke fragments generally accumulate on the exchanger tube sheets at the inlet to the tubes resulting in an excessive pressure drop and loss of heattransfer duty. Exchanger manufacturers association, sample problem book for 6th edition. A heat exchanger is a devices used to transfer heat between mediums.
Floating head heat exchanger is widely used for the service where the temperature is high between the shell and tube bundle, or the dirty service, like the petroleum refinery. The tubes may be permanently positioned inside the shell fixed tubesheet exchanger or may be removable for ease of cleaning and replacement floating head or utube exchanger. Tubeandshell heat exchanger in which the tube sheet at one end of the tube bundle is free to move explanation of internal floating head exchanger. Heat exchanger inspection heat exchanger pipe fluid. These and other components are described in the heat exchanger design handbook. Exchanger inspection 101 free download as powerpoint presentation. Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Internal floatinghead exchanger article about internal. The welding and testing procedures in these instances shall be mutually agreed. Identification, visual appearance and dimensions, weld control, pt, section of weld, macroobservation, hardness check of weld metal and heat affected zone are checked as required. Heat exchanger tube bundle extraction process duration.
Heat exchanger design handbook mechanical engineering. Completely revised and updated to reflect current advances in heat exchanger technology, heat exchanger design handbook, second edition includes enhanced figures and thermal effectiveness charts, tables, new chapter, and additional topicsall while keeping the qualities that made the first edition a centerpiece of information for. Gbt 294652012 shell flangerear head end of floating heat exchangers. The term heat exchanger applies to all equipment used to transfer heat between two streams. Defining the major tema constructions and identifying their advantages, limitations and applications suitable for each type can be advantageous to your process. Along the length of the tubes tube tube sheet joints can be visually inspected and standard ndt techniques, like penetrant testing or magnetic testing can be utilized. However, the term is commonly used to equipment in which two process streams exchange heat with each other. There are two main categories of shell and tube exchanger. The ring which is split in half to permit dismantling is placed at the back of the tube sheet shows the details of a split ring assembly. Shell and tube heat exchangers are one of the most popular types of exchanger due to the flexibility the designer has to allow for a wide range of pressures and temperatures. Selecting tema type heat exchangers 20020601 process. Dec 16, 20 most process shellandtube heat exchangers are manufactured to tubular exchanger manufacturers association tema standards. The manufacturer shall carry out the inspections required by the asme code, customer. There are many areas on a heat exchanger that you can not get to for visual inspections while the heat exchanger is in the furnace.
Tubeandshell heat exchanger in which the tube sheet at one end of the tube bundle is free to move explanation of internal floatinghead exchanger. R sekulib university of kentucky introduction a heat exchanger is a device that is used for transfer of thermal energy enthalpy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a. We have been facing frequent failures in floating head joint of split ring type shell and tube heat exchangers. There are a variety of methods of inspecting or testing heat exchangers. Lewin heat exchanger design shellandtube heat exchangers 12 fixed head 12 floating head. Iimaterials and section vnon destructive testing are also relevant. Above these temperature differences problems of differential expansion arise. Find out information about internal floating head exchanger. Both ends of u tube are fixed in the same tube sheet. This heat exchanger requires periodic cleaning, replacement of tubes etc. Find out information about internal floatinghead exchanger.
Illustrates the shell and u tube type heat exchangers commonly. Like with most equipment, inspection planning is essential for the successful inspection and maintenance of heat exchanger tubulars. By passing of shell side fluid is minimum due to minimum clearance between the shell. So please participate and share knowledge just as you have in the past. Floating head shell and tube exchangers floating head exchangers are used when the media being handled causes fairly rapid fouling and the temperature creates expansion problems.
This presentation is about maintenance procedure for floating head heat exchanger. These standards include a threeletter designation of the exchanger type that specifies overall mechanical layout in the form. We have included on that figure the nomenclature to be used in subsequent derivations. Furnace heat exchanger documentation book highly informative book contains over 363 high resolution photos of heat exchanger failure, representing 109 different furnaces. Sample activities for heat exchanger cleaning and inspection work activities and work steps are very useful information. Understanding heat exchanger reading 03 part 2 of 2 the aramco std.
Floating head is held in position by a split backing ring so that dismantling is possible. Most process shellandtube heat exchangers are manufactured to tubular exchanger manufacturers association tema standards. Aesaet these units are the most expensive of the removable bundle designed units. Exchanger inspection 101 corrosion heat exchanger scribd. These are used when shell side fluid is clean and nonfouling. In the focus on finding failure advanced class for heat exchanger inspection training, each technician will learn how to increase their ability to be truly focused on finding failure to incredible levels. Heat exchanger inspection planning inspectioneering.
Floating head is fitted to the tube sheet which is away from the channel. What is the function of floating head in heat exchanger. This is a handson tech teaching tech workshop on greatly increasing your abilities at finding failure using the inspector camera. The simplest is a pullthrough design which allows the tube bundle to be pulled entirely through the shell for service or replacement. The floating tubes sheet is clamped between the floating head and a clamp ring. Third party inspection for shell and tube heat exchanger. Plate type heat exchangers all inspection and maintenance is to be. Aug 18, 2014 this presentation is about maintenance procedure for floating head heat exchanger.
Mockup test is made when required by purchase order or contract. All new posts will show up credited to their authors. Floating head designs of head exchangers in an effort to reduce thermal stresses and provide a means to remove the tube bundle for cleaning, several floating rear head designs have been established. Induceddraft furnace heat exchanger inspection procedure. If you continue browsing the site, you agree to the use of cookies on this website.
The heat exchanger inspection article provides you with information about the inspection of the heat exchanger and heat exchanger testing during the manufacturing phase, as well as inservice inspection in operating units. The documentation book furnace heat exchanger failure the. Since 1979, he has consulted on a variety of problems with process and power generation heat exchanger problems. They need the documentation book for furnace heat exchanger failure. Jan 25, 2018 the floating tubes sheet is clamped between the floating head and a clamp ring. Heat exchanger design handbook kuppan thulukkanam this comprehensive reference covers all the important aspects of heat exchangers hes. Jun 01, 2002 tema is a set of standards that defines the heat exchanger style and machining and assembly tolerances to be employed in the manufacture of a given exchanger. Tubular heat exchanger inspection, maintenance, and repair. Floating head heat exchanger is one of the most used heat exchanger. Heat exchangers floating heads or tube bundles manufacture of.
Floating head versus u tube heat exchanger chemical. A floating head exchanger is suitable for the rigorous duties associated with high temperatures and pressures but is more expensive typically of order of 25% for carbon steel construction than the equivalent fixed tubesheet exchanger. Sonomatic provides a range of inspection and integrity services for heat exchangers and tubing. When migrating the old forums over to our new forums we were unable to retain the identity of the authors, so the old posts will show up as anonymous. Internal floatinghead exchanger article about internal floatinghead exchanger by the free dictionary. Special designs are available for particulate ladened air streams, corrosive applications, high temperatures, and high pressures. Generally, both the shell and tube bundle are free of expansion, this permits no thermal stress is produced between shell. In general the tubes in the heat exchanger undergoes expansion when there is a temperature gradient, now if both side of the tubes are firmly fixed then it may bulge as there is no provision for expansion in order to avoid this the tube side bundl. Fixed and floating head pressure comparison for madison. There are several rear header types that can be used but the stype rear head is the most popular. Lewin heat exchanger design shellandtube heat exchangers 12 fixed head 12 floating head 7 6 plant design daniel r.
Floating head heat exchanger with removal bundle a fixed tube sheet heat exchanger is the cheapest because of the ease of fabrication. Cn102359850a assembly for pressure test of floating head. Tube bundle can be removed for cleaning and inspection. These heat exchangers are made from quality metal which is corrosion resistant and withstands tough weather condition. This approach means inspection of the shell can take place without the need to remove the tube bundle. This comprehensive reference covers all the important aspects of heat exchangers hestheir design and modes of operationand practical, largescale applications in process, power, petroleum, transport, air conditioning, refrigeration, cryogenics, heat recovery, energy, and other industries. Completely revised and updated to reflect current advances in heat exchanger technology, heat exchanger design handbook, second edition includes enhanced figures and thermal effectiveness charts, tables, new chapter, and additional topicsall while keeping the qualities that made the first edition a centerpiece of information for practicing engineers, research, engineers, academicians. Tubes can be cleaned mechanically, chemically, water blasted or steam cleaned. Tubesheets in fixed and floating head heat exchangers.
The choice of shell and tube type is determined chiefly by factors such as the need for the provision for differential movement between shell and tubes, the design pressure, the design temperature, and the fouling nature of the fluids rather than the function. Heat exchanger inspection free download as pdf file. Heat exchangers jordan university of science and technology. Shell and tube exchangers an overview sciencedirect topics. In addition, a number of different head and shell designs are. Floating head heat exchanger on sales quality floating head. Tema stands for tubular exchanger manufacturers association, the tarrytown, n. Advantages and disadvantages of fixed tube sheet heat exchanger advantages. Fixed and floating head heat exchanger constructions find widespread. This revolutionary solution eliminates heat exchanger failure for industry leading equipment life without any maintenance. Gbt 294652012 shell flangerear head end of floating heat exchangers ics 23.