High pressure coil steam generators – UM-HP series

• The coil’s dimensions, large furnace, low thermal load, and low-pressure drops assure steam circulation already at low pressure
• Fully customized for special and demanding applications
• Natural circulation steam generator for high-pressure applications

• Minimum water level control realized with one self-checking probe, which allows us to reduce the circuit’s water content, necessary for the inertia of old water control systems
• Long service life ensured by 16Mo3 steel coil design
• Stable steam circulation even at low operating pressure
• Ideal solution for food industry processes and edible oil refineries

The UM-HP series consists of natural circulation steam generators designed for high-pressure and high-temperature operation. The coil is manufactured from seamless 16Mo3 steel and is specifically engineered to ensure long-term reliability, even under challenging working conditions, with steam pressures up to 100 barg and temperatures up to 312°C.

The coil geometry, combined with a large furnace volume, low thermal load, and minimized pressure drops, ensures stable steam circulation already at low operating pressure, contributing to safe and efficient performance. Unlike traditional rising-pipe boilers, the UM-HP coil design guarantees constant and controlled pressure drop, eliminating circulation instability and the associated mechanical risks.

The continuous coil configuration avoids welded connections between pipes and collectors, preventing mechanical stress concentration and welding-related issues. Moreover, the coil ensures homogeneous thermal expansion during warm operating conditions, eliminating differential dilatation typically found between upper and lower collectors and piping in conventional designs.

The once-through, vertical coil-type arrangement further enhances compactness and operational flexibility. This proven technology makes the UM-HP particularly suitable for food industry processes and, in particular, for edible oil refineries, where precise thermal control and continuous operation are essential. Designed for special applications, UM-HP boilers are fully customized to meet specific customer requirements, ensuring optimal performance in every installation.

The UM-HP steam generator operates on a natural circulation principle supported by a dedicated by-pass and piping layout designed to ensure safe and reliable operation under all conditions. During start-up, the by-pass assists water circulation together with the water reserve, preventing delays in the return line. During normal operation, the by-pass also acts as a steam separator, facilitating the separation of steam from water and supporting stable natural circulation within the system.

The piping circuit is designed with a required slope of 5% (minimum 3%) to ensure proper condensate return and avoid stagnation. The dimensioning of the water reserve is a critical design parameter and is defined based on the water volume contained in the deodorizer, the operating mode (continuous or batch), and the working pressure of the system.

A condensate flow probe is installed to detect the effective return of condensate to the steam generator. For correct operation, the lowest part of the probe rod must be positioned at least 1,500 mm above the boiler cover.

From a safety standpoint, the system is designed to immediately stop the burner in the absence of water or condensate circulation, preventing damage to the coil and ensuring safe steam generator operation.