Steam Drum Function

Water circulates through boiler tubes absorbing heat producing steam-water mixture. Drum receives mixture providing residence time for gravity separation. Steam rises collecting in upper section. Water returns to downcomer tubes continuing circulation. Separated steam flows to superheater or turbine.

Operating Pressure

High-pressure service typically 600-2400 psig for industrial boilers and HRSG systems. Subcritical pressure for most applications. Design pressure per ASME Boiler Code with appropriate safety factors. Temperature follows saturation conditions at operating pressure.

Drum Design

Horizontal cylindrical vessel with steam-water inlet from riser tubes, internal separation equipment including cyclone separators and chevron driers, steam outlet to superheater, downcomer connections returning water to furnace, feedwater inlet, blowdown connection, level and pressure instrumentation.

Internal Separation

Primary separators use centrifugal force removing bulk water from steam. Secondary stage chevron or mesh driers capture remaining droplets. Multi-stage separation achieves 99.5%+ steam quality. Critical for preventing water carryover damaging turbines or superheaters.

Material Selection

Carbon steel or low-alloy steel construction per ASME Boiler Code Section I. Materials rated for high-pressure high-temperature service. Welding procedures qualified for boiler fabrication. Radiographic examination verifies weld integrity.

Water Chemistry

Feedwater treatment removes oxygen, minerals, and contaminants preventing scaling and corrosion. Chemical dosing maintains proper pH and prevents carryover. Blowdown removes concentrated impurities. Water quality critical for drum and system longevity.

Level Control

Three-element control uses drum level, steam flow, and feedwater flow maintaining proper water inventory. Prevents low level exposing tubes causing failure. Prevents high level causing carryover. Automated systems ensure safe operation.

Applications

Power plant utility boilers, industrial process steam generation, waste heat recovery steam generators behind gas turbines, combined cycle power plants, and any high-pressure steam production requiring drum separation.

Circulation

Natural circulation uses density difference driving water flow. Forced circulation adds pumps for higher heat flux. Circulation rate ensures adequate tube cooling preventing burnout. Drum design supports circulation pattern.

Blowdown System

Continuous or intermittent blowdown removes concentrated solids preventing drum foaming and carryover. Bottom blowdown removes sediment. Surface blowdown skims floating contaminants. Proper blowdown maintains water quality.

Pressure Parts

Drum connections for risers, downcomers, feedwater, and steam outlet designed per boiler code. Nozzles reinforced for pressure loads. Thermal expansion accommodated in piping design. Supports allow movement during operation.

Performance Benefits

Provides reliable steam-water separation ensuring dry steam quality. Maintains water inventory for safe boiler operation. Critical component in power generation and industrial steam systems.

Construction Standards

Fabrication per ASME Boiler Code Section I with S-stamp. Materials meet code requirements for pressure and temperature. Hydrostatic testing at 1.5x design pressure. Complete documentation with code calculations and certifications.

ERGIL HP steam drums deliver reliable high-pressure steam separation in boilers and heat recovery systems for power generation applications.