Watlow Immersion Heater

Protection and Control: The terminal box type is similar to the screw plug type, supporting universal, moisture-proof, explosion-proof, etc. It can also be matched with thermocouples and thermostats to achieve precise temperature control and monitoring.

3. Customization and adaptation

Support customization of flange size, pressure rating, and component arrangement according to customer needs. We can also provide flanges and components made of special materials to cope with harsh working conditions such as corrosion or high temperatures. For example, when dealing with highly corrosive solutions, flanges and components made of Hastelloy material can be used.

Typical application scenarios and adaptation solutions

（1） Water heating

1. Heating of clean water

Product selection: Common 1-inch, 1.25-inch, 2-inch, 2.5-inch NPT spiral plug heaters, paired with WATROD or FIREBAR components. Taking a 1-inch NPT screw plug as an example, if Alloy 800 sheath components are used, the power density can reach 60 W/in ² (9.3 W/cm ²), and the power can range from 0.5kW to 4kW at 240VAC. It is suitable for small water tanks, laboratory water heating and other scenarios.

Configuration options: Universal terminal box or moisture-proof terminal box can be selected, paired with SPST thermostat (temperature range 30-250 ° F or 175-550 ° F), such as models BCN4J1S2 (Type 2 temperature range) and BCN4J1S3 (Type 3 temperature range), both of which support next day shipping (RS identification).

2. Heating of deionized water/desalinated water

Material adaptation: Due to the possible corrosiveness of deionized water, components with 316 stainless steel plugs and 316 stainless steel sheaths are usually selected, such as 2.5-inch NPT spiral plug heater, model BLR77L3S4, sheath material of 316 stainless steel, power 3kW, voltage 240VAC, power density 9.3 W/cm ², which can effectively resist the corrosion of deionized water and ensure long-term stable operation.

Control and Protection: K-type thermocouples can be equipped for precise monitoring of process temperature. The terminal box is selected as moisture-proof and explosion-proof, suitable for environments that may be humid or have slightly corrosive gases.

3. Heating of process water

Product type: Depending on the flow rate and heating requirements of the process water, a 1.25-inch NPT FIREBAR element heater or a 2-inch NPT WATROD element heater can be selected. For example, a 1.25-inch NPT FIREBAR heater, model BDNF13A27S5A, with a power of 2.0kW, a voltage of 240VAC, and a power density of 7 W/cm ², is suitable for heating medium flow process water; 2-inch NPT WATROD heater, model BGS79J6S4, power 1.0kW, voltage 120/240VAC, compatible with different process equipment interfaces.

Installation requirements: It is necessary to ensure that the heater is installed on the path of the process water flow, and that the components are completely immersed in the water to avoid dry burning. At the same time, the installation angle of the components should be adjusted according to the direction of the water flow to improve heat transfer efficiency.

（2） Heating of oils and viscous media

1. Heating of light oil and heat transfer oil

Power density control: Due to the relatively low heat transfer efficiency of oils, heaters with medium power density, such as 23 W/in ² (3.6 W/cm ²), are usually selected. Taking the 1-inch NPT WATROD heater as an example, model BCS6J1S, with steel sheath material, power of 0.25kW, voltage of 120VAC, suitable for heating lightweight lubricating oil; 1.25-inch NPT WATROD heater, model BES6G6S, power 0.5kW, voltage 120/240VAC, can be used for heating heat transfer oil.

Structural design: Some models use flat FIREBAR components, which can increase the contact area with oil and improve heating uniformity, such as the 1.25-inch NPT FIREBAR heater, model BDNF 16G12S5A, power 1.7kW, voltage 240VAC, suitable for small oil tank heating.

2. Intermediate oil heating

Low power density adaptation: Medium quality oil has poor fluidity and requires the use of a lower power density heater, such as 15 W/in ² (2.3 W/cm ²), to avoid local overheating and carbonization of the oil. For example, a 1.25-inch NPT FIREBAR heater, model BDNF 13A29S5A, with a power of 0.67kW and a voltage of 240VAC, is suitable for heating medium lubricating oil; 2-inch NPT WATROD heater, model BHN79N12S4, power 1.0kW, voltage 240VAC, suitable for heating medium quality oil storage tanks.

Temperature control: Equipped with DPST thermostat with a temperature control range of 60-250 ° F to prevent excessive oil temperature. At the same time, a low level sensor can be selected to avoid dry burning and damage to the heater due to low oil level.

3. Heating of heavy oil, asphalt, and # 6 fuel oil

Extremely low power density: This type of medium has extremely high viscosity and poor heat transfer efficiency, requiring the use of heaters with extremely low power density, such as 8 W/in ² (1.3 W/cm ²). For example, a 1.25-inch NPT FIREBAR heater, model BDNF 16G22S5A, with a power of 0.43kW and a voltage of 240VAC, is suitable for the initial stage of asphalt heating; 2.5-inch NPT WATROD heater, model BLS717E12S4, with a power of 1.0kW and a voltage of 240VAC, can be used for heating and insulation of # 6 fuel.