TEMA Shell and Tube Heat Exchanger Types Explained

The Tubular Exchanger Manufacturers Association (TEMA) standard describes shell-and-tube heat exchangers with a three-letter code: front-end stationary head (A–D), shell type (E–K, X), and rear-end head (L–W). 'BEM', for example, is a bonnet front head, single-pass E-shell, and fixed tubesheet rear head — a low-cost, fixed-bundle design used for clean services.

Type A (channel with removable cover) allows tube cleaning without disturbing piping — preferred for fouling services. Type B (bonnet integral with tubesheet) is lower cost but requires piping removal for tube access. Types C and D are for high-pressure services with integral channels welded or bolted to the tubesheet.

Type E is the standard single-pass shell — most common. Type F is two-pass with a longitudinal baffle, used when temperature cross requires counterflow. Type J is a divided-flow shell for low pressure drop. Type K is a kettle reboiler with enlarged shell for vapour disengagement. Type X is a pure crossflow shell for very low pressure drop, common in gas coolers.

Type L, M, N are fixed tubesheet — lowest cost, no bundle removal, requires expansion joint for large temperature difference. Type P, S, T are floating-head designs allowing bundle removal and accommodating thermal expansion. Type U is a U-tube bundle — bundle removable, single tubesheet, but tubes cannot be individually cleaned mechanically. Type W is an externally sealed floating tubesheet for special services.

BEM and BEU: clean services, lowest cost, fixed-bundle or U-tube. AES and AET: fouling services, removable bundle, full mechanical cleaning access. AKT: kettle reboiler with removable bundle for hydrocarbon service. BFU: F-shell two-pass with U-tubes for temperature cross with bundle removal capability. Each combination trades off cost, maintainability, thermal expansion and access.

Send the operating conditions (hot and cold side medium, temperatures, flows, pressures), the fouling tendency of each side, and any maintenance philosophy (in-place cleaning, bundle pull, chemical clean only). The engineering team will recommend the front-end / shell / rear-end combination that meets the duty at the lowest installed cost. Jiangxing supplies TEMA-designation shell-and-tube heat exchangers in single-pass, multi-pass, U-tube and floating-head configurations to ASME, PED and GB codes.