Steam Boilers – ELV Range
The ELV range of boilers is available from 12.5 kW to 120 kW – steam output up to 190 kg/h (420 lb/h) from and at 100:C, at working pressures up to 10.3 barg (150 psig). Higher pressures are available.
The boilers use Incoloy sheathed immersion elements of a low surface loading. This, combined with high quality components ensures a long, trouble-free life with the minimum of maintenance.
The boilers are free-standing and packaged complete with all controls, feedwater tank and feedwater pump mounted in a mild steel enclosure. All components (including the top mounted element flanges) are easily accessible via removable covers.
A stainless steel version is available with all wetted parts in stainless steel. Manual blowdown is a standard feature options avaiable for the ELV range include Auto timed blowdown, TDS controlled blowdown .
Thryristor pressure and temperature control is an option for this boiler
The thyristor controlled boiler has the same vessel and comprehensive controls, low surface loading Incoloy sheathed elements mounted with thermocouplers and easily withdrawable element flanges as our standard boiler.
The only difference is the thyristor control of load regulation with no direct on-load switching by contactors.
Load regulation is by means of a burst–firing thyristor controlling the three phase load. Thyristor switching occurs at zero voltage.
The analogue output from a pressure or temperature transducer is input to a process controller whose logic output is input to the thyristor.
At start-up, with 100% demand, the thyristor output is 100%. As the boiler pressure or temperature approaches the set point, the process controller modulates the output of the thyristor to maintain the pressure or temperature at the set point. The thyristor continues to modulate to ensure that the energy input is precisely matched to the demand.
The benefits of using this system are:
- Smooth load changes from 0–100%.
- Increased element life due to the reduction of thermal shock on the element resistance wire.
- Precise matching of load to the demand.
- Very low maintenance costs.
