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This post was last edited by yuun on 2019-10-22 at 10:30. TEMA 2019 update: TEMA has recently released its 2019 version (the tenth edition). It has been 12 years since the 2007 version was released, and many people are curious to know what changes have been made This article will introduce the new updates to TEMA, serving as a starting point; if there are any omissions, please feel free to point them out. The main updates in the 2019 version are as follows: New additions: Numerical analysis of expansion joints (1D FEA), design rules for horizontal saddles, dimensional data for flanges, guidelines and configurations for the inlet distribution section of the shell side, studies on design to reduce scaling, guidelines for expansion welding of tube-sheet joints, sketches of shoulder bolts for detachable tube banks, bolt connections recommended in accordance with ASME PCC-1. Updates: Updated international material tables, updated data tables for metric bolts, modernized and standardized format for graphics and charts. More details on these updates can be found on the official website: http://www.tema.org/highlight10.asp. TEMA’s official website is: http://www.tema.org. Below is an analysis of the specific changes in each chapter. The numbering rule for TEMA has been improved in the 2019 version. For example: in version 2007, the code is RCB1.42; in version 2019, it is RCB1.4.2.1. Version 2007 makes it easy to think that this refers to sub-item 421 of the first item. The 2019 version has a clearer hierarchy; this provision indicates that there are four levels of tree branches, in line with the internationally accepted modern standardized numbering rules. G-2.1 Inspection requirements 2007: The manufacturer shall carry out the inspections required by the ASME Code. 2019: The manufacturer shall carry out the inspections required by the Code. Interpretation: The ASME reference is removed in the newer version of the inspection requirements; this is likely because the specifications regarding inspections and tolerances in the ASME Code are not as detailed as those in TEMA. TEMA is primarily a structural specification for heat exchangers, with stricter requirements for structural dimensions than ASME. G-3.1 Name plates 2007: Name plates for exchangers manufactured in accordance with Classes “R” and “B” shall be made of austenitic (300 series) stainless steel. When the insulation thickness is specified by the purchaser, the name plate shall be attached to the bracket welded to the exchanger. 2019: The name plate may be attached via a bracket welded to the exchanger, and shall be visible outside any insulation. Interpretation: The new version removes the requirement that name plates for TEMA “R” and “B” classes must be made of 300 series stainless steel. The nameplate must be mounted on the nameplate bracket welded to the heat exchanger, and when insulation is present, it should extend beyond the outer surface of the insulation. The 2007 version in English can be understood as meaning that, when insulation is present, the nameplate must be mounted on a nameplate holder. What should be done if there is no insulation? The regulations for 2019 are more explicit: whether or not there is insulation, nameplates should generally be mounted on nameplate holders (to avoid being welded directly to the equipment). G-4.1 Interpretation of drawings for approval and changes: The division of responsibilities is described more clearly. It specifies the minimum information that drawings must contain, the format in which manufacturers should submit their drawings (PDF), and how to handle any modifications. If modifications result in increased costs, the manufacturer is responsible for informing the cost of those modifications. G-4.2 Drawing for record 2007: The manufacturer submits 3 paper copies. 2019: The manufacturer submits PDF electronic versions. Explanation: Submitting PDF versions is more convenient; if paper copies are required, it can be specified separately in the contract. Disclaimer, General Liability and Warranty Interpretation: New sections G-5.6, 5.7, 5.8 added, including a disclaimer, general liability, and warranty provisions. Overall, it is to protect heat exchanger manufacturers. It specifies the responsibilities of both parties, as well as exemption clauses; it is only liable for the written conditions provided by the buyer, and for example, it assumes no responsibility regarding whether the heat exchanger is suitable for a specific purpose. To address how to tighten bolts, new clauses E3.2.4.3 and E3.2.4.4 have been added; a requirement for tightening bolts is specified in E3.2.5. In line with ASME PCC-1, recommended procedures for tightening bolts are provided. Interpretation: In conjunction with the bolted connections recommended by ASME PCC-1. New E-5: Explanation of changes to the heat exchanger configuration: If it is necessary to modify the heat exchanger’s configuration, such as upgrading the materials, increasing the design pressure or temperature, or changing the type of gaskets used. Whenever components of the heat exchanger are changed, the impact on the overall design must be considered. After the changes, it is also necessary to meet the specifications and TEMA requirements. This applies both to design and renovation, reminding that it must also comply with regulations after renovation. For example, when modifying the gasket, it is necessary to check whether the flange thickness is suitable, to adjust the pressure and temperature, to consider the original strength, and to ensure that the flange grade meets the requirements, among other things. RCB-1.3.1 Hydrostatic test 2007:2019: Delete the requirement that, when the pressure on the tube side is higher than that on the shell side, the tube bundle should be pressurized outside the shell side. The purpose of this method is to subject the tube-sheet joint to stricter and more visible tests on both sides. The test pressure in the shell side is high; if a leak occurs during testing, it is possible to determine which heat exchange tube is faulty directly at the tube-sheet joint, allowing for appropriate corrective actions to be taken. However, when the test pressure for the tube side is high, with a fixed tube sheet, the interior is not visible. In the case of a hydrostatic test, if leakage occurs at the tube-sheet joints, it is impossible to determine which heat exchange tube is defective. Therefore, the standards recommend that the tube bundle be pressurized outside the shell side, so that the leaking heat exchange tube can be directly observed. However, for fixed-tube-sheet heat exchangers, it is not possible to perform individual pressure testing of the tube bundle due to structural constraints. Although the specification has been removed, its principle of being \"strict and visible\" remains valid. In China, this principle is generally implemented in two ways: if the pressure required for testing the tubes is not very high, it is possible to increase the pressure used for testing the shell side without affecting costs, such that the pressure for testing the shell side equals the pressure for testing the tubes. In another case, when the pressure in the tube side is much higher than that in the shell side, a leakage test (ammonia leak detection or helium leak detection) is employed on the shell side to determine which heat exchange tube is defective. Add RCB-1.4.2.3 Interpretation of MDMT: The minimum design metal temperature MDMT is generally specified by the buyer. The operating temperature, the lowest ambient temperature, and abnormal operating conditions such as self-cooling (for example, some devices emit compressed gas, resulting in a sudden drop in temperature at the outlet) need to be taken into consideration. MDMT is used to determine whether an impact test is necessary. RCB-1.5.1.2 Internal floating head covers: In 2007, it was specified that the corrosion allowance on the outside of the flanged portion could be included in the recommended minimum edge distance. In 2019, it was stated that no corrosion allowance needs to be added to the recommended minimum edge distances given in tables D-5 or D-5M. Interpretation of Page 38: The dimensions in tables D-5 and D-5M do not need to take into account the effect of corrosion allowance. It means roughly the same thing, but is expressed more clearly. RCB-2.2.2 Marking of integral finned tubes 2007: https://mmbiz.qpic.cn/mmbiz_png/DVnwQibl2L2k5m3Hcj5lFwN4KVoibkNyEPtak0CtsGPT2xj9TvY8aRiclCyia6H31NfNBZuXQeT8OXZo57okEDFsSg/640?wx_fmt=png 2019: Interpretation: The new requirements state that for integral finned tubes, the thicknesses of both the finned portion and the bare tube portion must be indicated simultaneously. RCB-2.3.1 U-bend requirement: Formula modification 2007: 2019: Interpretation: The formula for carbon steel remains unchanged. For duplex steel, super stainless steels, titanium, high-nickel alloy steels, and other tubes that undergo cold working hardening, the C value is set to 2, which results in an increased thickness required before bending. For R