Custom exchangers and like-for-like replacements for refineries, gas plants, power stations and marine duty. Designed and built in Hartlepool by AMI Exchangers, supplied and supported in the GCC by Petromarsh.
Tap a part to see what it does. The red line is the hot shell-side fluid, the blue line is the cooling fluid inside the tubes.
Channel (front head). Collects the tube-side fluid and splits it into passes. On an A-type the cover bolts off, so the tubes can be cleaned without removing pipework.
Tubesheets. Thick drilled plates that hold every tube end. Tubes are expanded or welded into them, and they separate the shell-side and tube-side fluids.
Tube bundle. Where the heat transfer happens. Tube size, wall thickness, pitch and material are chosen for the fluid, velocity and corrosion.
Baffles. Plates that steer the shell-side fluid back and forth across the tubes, raising heat transfer, and that support the tubes against vibration.
Shell and saddles. The pressure shell that contains the shell-side fluid, sitting on two saddles bolted to the foundation.
Floating head (S-type). The rear tubesheet is free to move as the tubes grow with heat, so no expansion joint is needed and the bundle can be pulled out.
Nozzles. Inlet and outlet connections for each fluid, flanged to your piping class. Size and orientation are agreed on the datasheet.
Two fluids at different temperatures pass each other without mixing. One runs inside a bundle of tubes, the other flows around the tubes inside a pressure shell. Heat moves through the tube walls from the hot fluid to the cold one.
Usually the dirtier, more corrosive or higher-pressure fluid, such as seawater or cooling water. Tubes are easier to clean and cheaper to make in special alloys than the whole shell.
The fluid enters the shell and is steered back and forth across the bundle by baffles. This cross-flow raises turbulence and heat transfer, and the baffles also support the tubes against vibration.
A pass partition in the channel sends the tube-side fluid down the shell and back again. More passes give higher velocity and better heat transfer, at the cost of more pressure drop.
Every shell-and-tube exchanger is named by three letters from the TEMA standard: the front head, the shell, and the rear head. Pick one of each to see what you get, or start from a common type.
The standard refinery exchanger. The bundle can be pulled for cleaning on both sides, and the floating head handles large temperature differences.
The heaviest construction, for petroleum and related process duty. Larger corrosion allowances and thicker tubes.
General process and commercial duty, where conditions are moderate.
Chemical process service, often with stainless or alloy materials.
Material choice decides how long an exchanger lasts. In the Gulf the usual enemies are seawater, chlorides, hydrogen sulphide and high ambient temperatures.
| Part | Carbon steel | Stainless and duplex | Special alloys |
|---|---|---|---|
| Shell and channel | Pressure plate and pipeSA-516 Gr 70 · SA-106 Gr B | 304L, 316L, duplex 2205SA-240 · SA-312 | Clad plate for corrosive dutyexplosion-bonded cladding |
| Tubes | Seamless or weldedSA-179 · SA-214 | 304L, 316L, duplex, super duplexSA-213 · SA-249 · SA-789 | Titanium, copper-nickel 90/10 and 70/30, admiralty brassSB-338 · SB-111 |
| Tubesheets | Forgings or plateSA-266 · SA-105 · SA-516 | Stainless forgingsSA-182 | Clad tubesheets, naval brass for marineSB-171 |
| Gaskets | Spiral wound, double-jacketed or solid metal, chosen for pressure, temperature and fluidASME B16.20 | ||
The datasheet names the code. We follow it, plus your company specification where one applies.
Construction classes R, C and B, the three-letter type names, tolerances and clearances.
Pressure vessel design rules for shell, channel and nozzles.
Extra requirements for shell-and-tube exchangers in petroleum, petrochemical and gas plants.
CE marking for Europe. UKCA under the Pressure Equipment (Safety) Regulations 2016 for the UK.
Material specifications, and qualified welding procedures and welders.
Non-destructive testing methods, and certified mill certificates for every pressure part.
Material limits for equipment exposed to hydrogen sulphide.
Nozzle flange ratings and dimensions, matched to your piping class.
Company specifications, such as Saudi Aramco 32-SAMSS-007, applied on top of the codes.
Your engineers red-line our drawings, you approve the design twice before production starts, and you can witness the tests. Tap a step to see what happens and which documents you receive.
AMI Exchangers has completed more than 25,000 projects for power, marine, chemical and oil and gas clients. Petromarsh is their exclusive representative in the GCC.
If you have a TEMA datasheet, send it. If you do not, the items on the right are enough for us to size the exchanger and reply with a proposal.
