scope:

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

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:

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

b. Containers with volumes less than 100 ft3 (2.8 m3)

c. Bolted containers operating at atmospheric conditions

d. Mechanically fastened shell or head courses with or without seal welding

e. Non-metallic material

f. Fluidized beds

g. Non-cylindrical shells

h. Containers requirements associated with mechanical agitation by motor-driven blade impellers

i. Portable transport containers

j. 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.