Gas PipingQuestion 244 of 360
A sizing table (0.5 psi drop, natural gas) shows that 3/4-inch schedule 40 pipe at a 40-foot run carries 170 cfh, and 1-inch pipe carries 320 cfh. A section must supply a 250,000 BTU/hr load over that 40-foot run. What is the smallest listed size that works?
a.1/2-inch pipe
b.3/4-inch pipe
c.1-inch pipe
d.No pipe in the table is large enough
Explanation
Convert the load: 250,000 divided by 1,000 equals 250 cfh. The 3/4-inch pipe carries only 170 cfh, which is not enough, but the 1-inch pipe carries 320 cfh, which exceeds 250. Therefore 1-inch is the smallest listed size that meets the demand at that length.
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