scope:

This Practice describes requirements for design, materials, fabrication, examination, testing, and shipping for cylindrical shell, single-wall containers for dry bulk solids (i.e., bins, hoppers, silos, and gravity blenders) having internal design pressures not exceeding 15 psig (103 kPa) and/or full vacuum external pressure at the top of the container in its normal operating position. Containers may be welded, shop- and field-fabricated, and shall generally be designed in accordance with the philosophy and requirements of the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1, henceforth referred to as the Code. Code inspections and stamping are not required for these containers.

The following are not covered by this Practice:

Containers with nominal diameters 2 ft (0.6 m) or less

Containers with volumes less than 100 ft³ (2.8 m³)

Bolted containers operating at atmospheric conditions

Mechanically fastened shell or head courses with or without seal welding

Non-metallic material

Fluidized beds

Non-cylindrical shells

Containers requirements associated with mechanical agitation by motordriven blade impellers

Portable transport containers

Containers containing "lethal substances" defined as poisonous gases, liquids, or solids of such nature that a very small amount of the gas, liquid, or solid mixed or unmixed with air is dangerous to life if inhaled or if contacting skin. See Code paragraph UW-2

Purpose

This Practice provides requirements for the construction of cylindrical atmospheric and low-pressure, welded, shop- and field-fabricated dry bulk solids containers (e.g., bins, hoppers, silos, and gravity blenders).