Floating Head Heat Exchanger / Design / TEMA / API (2024)

FAQs

What are TEMA standards in heat exchanger design? ›

TEMA Standards define the style of heat exchangers and the machining and assembly tolerances. They are divided in three major classifications, related to its duty: TEMA C – General Service. TEMA B – Chemical Service.

Generally, there are four basic types of floating head heat exchanger – outside packed stuffing box (TEMA P), outside packed lantern ring (TEMA W), the floating head with backing device (TEMA S), and pull through (TEMA T) designs.

The “two-thirds rule” from API RP 521 (API, 2008) states: For relatively low-pressure equipment, complete tube failure is not a viable contingency when the design pressure of the low-pressure side is equal to or greater than two-thirds the design pressure of the high-pressure side.

Floating head heat exchanger（As shown in Figure 1）: only one end of the tube plate at both ends is fixed with the housing, and the other end is free to move relative to the housing, which is called floating head.

The current edition of the TEMA Standard is the Tenth Edition, published in 2019. Worldwide, the TEMA Standard is used as the construction standard for most shell and tube heat exchangers. The standard is composed of ten sections: Nomenclature (see below)

TEMA B: TEMA B shells and tubes are used for chemical processes, such as the transfer of fluids between tanks and reactors. TEMA R: TEMA R shells and tubes are used in refinery applications, such as the transfer of fluids between processing units.

A floating head type heat exchanger is a type of shell and tube heat exchanger in which the tube sheet assembly is free and free to move within the shell or shell cover. These exchangers are widely used for the service where the temperature between the shell and the tube bundle is high, which creates expansion issues.

Key Differences of Fixed Vs Floating Head Heat Exchangers

The fixed head design offers stability, while the floating head design prioritizes accessibility. The choice depends on your application's demands and the level of maintenance required.

» 10/13 Rule for overpressure protection. 10/13 Rule Loss of containment of the low-pressure side of shell and tube heat exchangers to atmosphere is unlikely to result from a tube rupture where the pressure in the low-pressure side during the tube rupture does not exceed the corrected hydrotest pressure.

What are the formulas for heat exchanger design? ›

What is the fundamental formula for understanding heat transfer in a Heat Exchanger? The formula is Q = U ⋅ A ⋅ Δ T lm , where Q is the total heat transfer, U is the overall heat transfer coefficient, A is the surface area for heat transfer, and Δ T lm is the log mean temperature difference.

In counter-flow heat exchangers (at right) the fluids enter the exchanger from opposite ends. The counter current design is the more efficient design, in that it can transfer the most heat from the heat (transfer) medium.

The floating-head heat exchanger is a type of tube heat exchanger in which the tube sheet combination is independent and can move freely within the shell. This exchanger is widely used for services where the temperature between the shell and tube bundle is high, causing expansion problems.

The floating head design allows the tube bundle (where one fluid flows) to move axially within the shell (where the other fluid flows) due to changes in temperature or pressure, without stressing or damaging the tubes or the shell.

TEMA (Tubular Exchangers Manufacturing Association) is the preferred standard for the manufacture of shell and tube heat exchangers. The general descriptions of the three major TEMA classes are: TEMA C – General Service. TEMA B – Chemical Service. TEMA R – Refinery Service.

ASME is an abbreviation of "American Society of Mechanical Engineers". TEMA is an abbreviation of "Tubular Exchanger Manufacturers' Association".

The Tubular Exchanger Manufacturers Association, or TEMA, has developed standards that define the design, fabrication, tolerances, installation and maintenance of shell-and-tube type heat exchangers. The TEMA standard defines the main configuration of exchangers and the classification for usage in the industry.

TEMA (Tubular Exchangers Manufacturing Association) is the preferred standard for the manufacture of shell and tube heat exchangers.

The triple exponential moving average (TEMA) is a modified moving average designed to smooth large price fluctuations. This makes it easier to identify trends without the lag associated with traditional moving averages.