Circulation Heaters: Choosing the Right One

Circulation heaters can be used in a variety of fields ranging from oil and gas to chemical and construction industries. Versatile in nature, these heaters can be used both indoors and outdoors depending primarily upon the design and application.

Engineering factors to consider include:

  • the heat requirement for the application of the circulation heater
  • the selection of the appropriate vessel and flange material
  • the selection of the material used for the heating element sheath
  • the appropriate watt density

Skid Circulation Heaters 2In industries with lube oil and waste materials, circulation heaters often are made up of steel as it is less expensive and works sufficiently well enough. On the other hand, for water circulation heaters, stainless steel is used because it is non-corrosive even though it costs more.

Insulation is also a factor to consider. A well-insulated circulation heater will save money by reducing the amount of heat loss that occurs. When selecting the circulation heater for your use, take a closer look also at the watt density. Heaters are typically designed for the specific medium that will be heated, and the wattage will correspond to the appropriate flow rate of the medium.

Drain valves are also useful to have in many instances and can usually be added in any location. This helps with maintenance and in removing water and oil from the heater. Your heater also needs regular cleaning for calcium deposits and other buildups. So it is essential that your circulation heater is well made and easily accessible so that you can clean it out regularly.

Will your heater need to be moved periodically? For industries like oil, it is helpful to have skid-mounted vessels. Skid circulation heaters can be easily moved as a single piece from one area to another. You may also require mounting (vertical or horizontal) for your heater depending upon usage. Another factor to consider is also weatherproofing (such as protection against moisture) and placement in terminal boxes that are protected against explosions such as NEMA 7, particularly in hazardous conditions.

Determine its application:

How will you be using your circulation heater? Different demands require different heaters. Application factors to consider include:

  • examining the properties of the heated medium ranging from viscosity to corrosion, density and specific heating
  • checking for any contaminants present in the heating medium
  • determining how resistant the heater sheath material is to corrosion
  • figuring out the sheath watt density of the heating elements from watts/square inch to the flow rate
  • how the vessel is designed (what material it is made of) as this influences the fluid that is being heated (temperature and pressure)

In the oil and gas industry, circulation heaters can help in adjusting the level of viscosity for heating oils. For example, crude oil can enter through a vessel opening at a certain cooler temperature and then leave the vessel at a suitable temperature for easy flowing through a pipe. Through effective design of heaters, several substances ranging from oil to water, gas, viscous materials and solvents can be heated while in contact with each other within one enclosed space at one time. This is highly efficient.

Consider warranties and the corrosion policy:

When you buy a new circulation heater, the manufacturing company provides certain warranties. It is important to check what these include. Often sheath corrosion is not included if the lack of performance in the circulation heater results from conditions that the manufacturer cannot control. Hence when you buy a new circulation heater, it’s important to consider aspects that will reduce the likelihood of corrosion.