Circulation Heaters
Circulation heaters are highly efficient heating cells designed to heat liquids and gases as they flow through a pipe body. These units are compact, and easy to install. They offer primary heating or act as a backup/start up heating source to natural or forced circulation systems. Design specifications may require a unit to meet the boiler and pressure vessel code. Bucan can supply units that are designed, built and registered to the ASME code, with the applicable code stamps.
General construction:
Circulation heaters have either a screwplug or flanged immersion heater installed into a pipe body (also called a pipe vessel), which has inlet and outlet connections. An insulation jacket (up to 2") around the pipe is standard; this reduces heat loss through the shell. This design concept incorporates the rugged and durable features of tubular heaters with the flexibility of a heat exchanger.
Typical Heating Applications
- Hydraulic Oils
- Steam Super Heating
- Alkaline Cleaning Solutions
- Oils, Including Light to Heavy
- Water & Water Based Solutions
- De-mineralized or De-ionized Water
- Gasses (Air, Nitrogen, Natural Gas, Butane, Etc.)
Standard flanged circulation heaters
| Nominal vessel size | A | C (in) | D (in) | E | F (in) | G (in) | Inlet/outlet size (NPT) |
| 3" | Heated section of the heater | 5.5 | 7.5 |
A |
9.5 | 5.5 | 1" |
| 4" | 5.5 | 9.0 | 10.5 | 6.25 | 1 1/2" | ||
| 5" | 6.75 | 10.0 | 11 | 7 | 1 1/2" | ||
| 6" | 6.75 | 11.0 | 12 | 7 | 1 1/12" | ||
| 8" | 6.75 | 13.25 | 13.5 | 8.5 | 2" |
Standard Screw Plug Circulation Heaters
| Nominal vessel size | A | C (in) | D (in) | E | F (in) | G (in) | Inlet/outlet size (NPT) |
| 1" | Heated section of the heater | 1 1/12 | 3 3/4 |
A |
5 | 5 | 1" |
| 1 1/4" | 1 1/2 | 3 3/4 | 5 | 5 | 1" | ||
| 1 1/2" | 1 1/2 | 3 3/4 | 5 | 5 | 1 1/4" | ||
| 2" | 2 1/2 | 3 3/4 | 5 1/2 | 5 1/2 | 1 1/4" | ||
| 2 1/2" | 2 1/2 | 3 3/4 | 5 1/2 | 5 1/2 | 1 1/4" |
For design help call our technical staff and we can help guide you through the selection process.
- Sheath materials - selected to suit the liquid or gas being heated
- Connections - NPT nipples or flanged inlet and outlet connections
- Flange pressure ratings - selected based on the temperature and pressure design conditions
- Terminal Enclosures
- General Purpose (NEMA 1)
- Weather Resistant (NEMA 4, 4X)
- Hazardous Location (NEMA 7, 7X)
- Passivation - when required
- Support frames - for stand-alone mounting
- Vessel materials - steel, stainless steel, or other specialty metals
- Cross flow baffles - to improve heat transfer characteristics, when required
- Controls - built in thermostats, thermocouples, and high limit thermocouples
Vertical Mounting with terminal housing facing upwards
(Recommended for liquids)
The inlet pipe should be at the bottom.
This configuration will maintain the heating element immersed in liquid at all times.
Horizontal Mounting
(For liquids or gases)
The inlet and outlet pipes should be installed at the top, oriented upwards, with the inlet pipe close to the terminal box. This configuration will maintain the heating element immersed at all times when liquids are heated and minimize the terminal housing temperature when gases are heated.
Vertical Mounting with terminal housing at the bottom
(Recommended for gases)
The inlet pipe should be at the bottom. This configuration will minimize the terminal housing temperature.
