Steam is typically used as a head carrier in heating systems. But at high temperatures, steam requires a corresponding high operating pressure a high temperatures fluid is often required, and achieving this team can be controversial and expensive.
Thermal oil heaters are widely used for supplying heat up to 300° C at very low pressure
Thermal oil heaters are widely used supplying heat up to 300 °C at very low pressure , typically just the pressure required to pump the oil through the system. Comparing this to other heating fluid, e.g. steam, it would require a pressure of 85 bar to achieve this temperature. Thermal oil heating systems, as compared to other heating systems e.g. steam offer many advantages.
Thermal oil heaters are used in the following industries.
The design & construction of Thermal Oil Heaters require special skills. Due to the fact that we have a permanent top level quality control. We can offer Thermal Oil Heaters featuring the highest heating surface area. Efficiency, safety, reliability. The design is based on a forced circulation heater with two coaxial cylindrical tube coils. In witch three pass counter flow system as described below:
1st pass- The radiant heat from the flame of the burner is transferred to the thermal oil in the main combustion chamber
2nd pass-combustion gases then gases the space between the inner and outer tube coils, where the heat is transferred by convention.
3rd pass-The last convection pass is between the outer coil and the heater °s shell, where combusting gases are hereafter cooled.
The principle ensures that maximum heat transfer is achieved before the combustion gasses exit the heater, thus ensuring high thermal efficiency. Maximum heat transfer is also affected by thermal fluid velocity and heating surface area. To maintain fluid velocity and hence low heat flux rate, the coil cross rational and surface area is generously designed to keep film and bulk temperatures and linear velocity low pressure drop and also to protect the oil from degradation.
The design philosophy ensures that the film temperature in tubes is not exceeded beyond its permissible limits. We carry out analysis to determine whether this requirement is met for the parts of the tubes exposed to flame impingement. The maximum film temperature is also used to calculate the service life of thermal oil. Low film temperature, ensures longer life of oil.
The film temperature is at its highest. When the oil is subjected to the greatest thermal stress.
Our thermal design ensures a modest volume of the thermal oil relative to heater capacity and allows thermal expansion due to the high oil temperature. Furthermore. Coil life is extended by optimizing length to diameter radio, heat flux rate and series flow.
Packman supplies a comprehensive set of safety controls for Thermal Oil Heaters. The logic of control elements comply with the stringent regulations enforced by DIN 4754. There are many safety interlocks. Incorporated in the system. All of our heaters incorporate continuous flow monitoring with Differential pressure controllers. The flow monitoring is an essential element. As it measures and monitors the minimum flow rate if it drop and if it drops below a certain minimum value is shuts down the firing system.
Also the thermostats in the supply and return oil and in the flue gas are interlocked to the firing system and shall prevent an inadmissible temperature rise in the system. A level switch is also mounted on the expansion tank which is interlocked with the feed pump and burner.
Mounted on the expansive tank which is interlocked with the feed pump and burner.
Packman will integrate your desired control requirements from basic relay logic to advanced PLC to interface with your plant.