Circulation Heaters

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Circulation Heaters, also known as “in line heaters,” have uses in many applications. They can use steel, stainless steel, or titanium depending on the application. Lube oil and waste oil applications often use steel for circulation heaters. This is because it is fairly inexpensive compared to stainless steel counterpart.

Water circulation heaters use stainless steel because of its anti-corrosive qualities. In both applications, a pump flows the liquid, such as water or glycerol, through a closed pipe circuit. The liquid is reheated as it flows through the circulation heater.

Applications of Industrial circulation heaters

A major consideration for this application is viscosity. Electric circulation heaters generate heat, making the medium less viscous. The less viscous the fluid, the easier it is to pump through a circuit of pipes.

Industrial circulation heaters come in a range of watt densities. Watt densities are specifically designed for the medium they will heat. The required wattage to heat the oil or water is highly correlated to the flow rate (in GPM).

• The fluid enters through the inlet closest to the flange heater.
• Heat gets applied to the fluid as it flows within a vessel chamber.
• The fluid exits the outlet nozzle or flange.
• It circulates throughout the piping circuit.

Insulation is often required for vessels to preserve the heat within the vessel. This results in efficient heat application, reducing unnecessary costs through heat loss. Electric circulation heaters can use digital thermocouple probes or RTDs.

This allows them to maintain the oil or water at the preferred temperature. Many applications use liquids with low flash point. These require explosion-proof housing (NEMA 7) to avoid potential mishaps.

Circulation heaters heat fluids, gases, and oils efficiently in a closed-loop system. It offers uniform heat distribution and controls temperature for the process that requires consistency. It is used in petrochemicals, food processing, and power generation, as they heat substances like water, fuel, hydraulic fluids, and corrosive liquids.

These heaters contain built-in thermostats for safety and energy efficiency and reduce heat loss. Its compact design helps to integrate into pipelines, and storage tanks and making them essential to maintain optimal process conditions in industrial environments.

Circulation Heater Types and Variations

There are many types and combinations of circulation heaters to serve industrial heating needs. Familiarity with heater types can help ensure the correct heating solution for your application:

Water Circulation Heaters

These heaters are designed specifically to heat water or other non-corrosive aqueous solutions, and often use stainless steel elements to resist corrosion and deteriorate less with use. Water circulation heaters are popular in boiler systems, hot water storage, and cooling towers.

Electric Circulation Heaters

Circulation heaters of this type use electric energy to produce heat to warm the circulating fluid directly. They are inherently efficient, reliable, and used in many industrial applications, making electric the most common type of heater for inline heating solutions.

Oil Circulation Heaters

These heaters are designed specifically to heat oils or other viscous liquids and often use steel heating elements to sustain higher temperatures and durability due to the typical viscosity of an oil. Oil circulation heaters are popular for use in lubrication systems and fuel heating.

Circulation Heaters with Pumps

Some systems will contain a pump and heater combination that will move fluid through a closed-loop system. When this is done using a circulation heater and pump, this will promote uniform heating of the fluid and effectively transported through piping.

Skid-Mounted Circulation Heaters

These are portable or semi-portable heater assemblies that are pre-mounted on steel skid frames. They consist of heaters, piping, pumps, controls, and instrumentation to create a single transportable heating unit that can be installed quickly in a temporary or remote industrial setting.

Each category provides an appropriate balance of material, power, installation, and flow considerations to provide optimal performance in the intended application. Selecting the proper circulation heater is dependent on the parameters of the medium to be heated, temperature requirements, flow, and safety factors.

Circulation Heating Shipping

Wattco uses its decades of experience shipping our industrial heaters worldwide. When shipping across borders, Wattco can handle all necessary import, customs and duties responsibilities to ensure that you receive your product on time and on spec.

Wattco ships using all mediums upon request including: truck, train, container ship and by air freight when mission critical rush delivery is required.

Wattco Circulation Heater Features

Other useful features found with electric circulation heaters are drain valves. They are easy to install  in any location on the vessel, allowing for easy maintenance of the heater. The water or oil can be purged through the drain valve allowing for maintenance on the heating elements. Calcium deposits and other residues can build up on heating elements. These require cleaning several times a month.

Circulation heaters also come with horizontal or vertical mounting, depending on your application. Skid mounted vessels are used in oil heating industries that require mobility. WATTCO™ circulation heaters are also available in different terminal boxes.

These include moisture resistant or explosion proof terminal boxes for hazardous environments. WATTCO™ circulation heaters are an exceptional choice for heating process liquids. They use materials that are resistant when heating corrosive mediums.

Usage of Wattco Circulation Heaters

The advantage of Wattco’s circulation heaters is heating the fluids in a closed-loop system. The applications of circulation heaters are multiple and distinct.

• The circulation heaters are used in oil refineries, petrochemical plants, and pipelines for heating crude oil, natural gas, and other petroleum products.
• It is used in the food and beverage industry for cooking, pasteurization, and mixing purposes.
• It is used in the plastic and rubber manufacturing industries that heat the plastics and rubber at a specific temperature for molding and extrusion.
• The circulation heaters are used in the welding process to preheat the metals before forging.
• The circulation heaters are implemented in large buildings or industrial facilities.
• It is used in the air-handling units that control the temperature of HVAC systems.
• Used in industrial and commercial hot water systems such as hotels and large buildings.
• Uses in the oil or gas pipelines to maintain the temperature and prevent it from freezing or viscosity issues.
• It heats the oil and gas stored in tanks to verify the proper flow. 
• Used to preheat the engine to check the optimal performance and start-up efficiency in cold conditions.
• Used in solar thermal systems to stabilize the temperature of a transfer fluid.
• It is used in research laboratories to provide consistent temperature control for experiments and processes.
• Used in the marine to heat the fluid in the shipboard system for propulsion and other needs.
• Used in aircraft systems to maintain the optimal temperatures.
• It is used in the pulp and paper industry to heat the water and chemicals.
• In the textile industry, it is used for heating the fluids during dyeing and finishing.