Bullet Design

Horizontal orientation with hemispherical or ellipsoidal heads minimizes steel weight while withstanding internal pressure. Length-to-diameter ratio typically 3:1 to 6:1 optimizes structural efficiency. Saddle supports allow thermal expansion. Capacities range 50-1000 m³ (13,000-264,000 gallons) providing surge volume for production, storage, and distribution operations.

Operating Conditions

Design pressure 16-25 bar accommodates LPG vapor pressure at maximum ambient temperature typically 50°C. Full refrigeration not required as vessels operate at ambient storing liquid under its own vapor pressure. Materials rated for pressure and temperature cycling. Relief valves protect against fire exposure and overfilling scenarios.

Material Selection

Carbon steel construction per ASME Section VIII suitable for LPG service. Proper steel grades for pressure vessel fabrication. Radiographic examination of welds. Impact testing for low-temperature service where required. External coating and cathodic protection prevent atmospheric corrosion. Insulation optional for sun exposure.

Applications

Refinery LPG storage between depropanizer and loading, gas plant propane and butane product storage, petrochemical feedstock surge tanks, distribution terminal buffer storage, and peak-shaving propane supply. Serves facilities requiring pressurized LPG storage without refrigeration from 50 to 1000 m³ capacity.

Safety Features

Pressure relief valves sized per API 521 for fire exposure. High-pressure alarms warn of abnormal conditions. Emergency isolation valves enable remote shutdown. Flame arresters where atmospheric vents present. Installation per NFPA 58/59 LPG codes with proper setbacks. Grounding prevents static accumulation.

Level and Pressure Control

Level gauges and transmitters monitor inventory. High-level alarms prevent overfilling. Pressure gauges indicate vapor pressure. Temperature monitoring tracks conditions affecting pressure. Integration with loading and production systems manages inventory and transfers.

Design Standards

Constructed per ASME Section VIII Division 1 or 2 with U-stamp. Fabrication per AWS welding codes. Hydrostatic testing at 1.5x design pressure validates integrity. Foundation design for vessel weight plus liquid load and seismic forces. Complete calculations, drawings, and material certifications.

Performance Benefits

Efficient pressure storage without refrigeration reduces capital and operating costs. Horizontal configuration suits plot layouts. Proven bullet design with decades of LPG service. Reliable storage for production buffering and distribution. Minimal maintenance with proper materials and construction.

Inspection and Maintenance

Periodic external inspection per API 510. Internal inspection per regulatory intervals. Cathodic protection monitoring. Relief valve testing and certification. Simple access for maintenance with proper procedures.

ERGIL bullet-type LPG buffer tanks deliver dependable pressurized storage for propane and butane in refining, gas processing, and distribution applications.