Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contactus/.
Click here to Find a Contractor in your area.
test quest.
bobbyg22
Member Posts: 1
This question appears in a prep book for a civil service test. (Steamfitter)
If a 2" diameter pipe discharges 20 gallons of fluid per minute, a 4" diameter pipe under similar conditions (such as internal friction and pressure head) would discharge APPROXIMATELY 64 gallons of fluid pre minute.
It's a true/false question. Is there a formula to arrive at the answer?
If a 2" diameter pipe discharges 20 gallons of fluid per minute, a 4" diameter pipe under similar conditions (such as internal friction and pressure head) would discharge APPROXIMATELY 64 gallons of fluid pre minute.
It's a true/false question. Is there a formula to arrive at the answer?
0
Comments

try one of these
There are several equations here, maybe one of them will help you.
http://www.efunda.com/formulae/fluids/calc_pipe_friction.cfm#calcsteam newbie0 
False
Area of 4" is 6 times 2" ?0 
square
the area of a pipe cross section is proportional to the square of the actual inside diameter. If we assume that the actual inside diameter of a 4 inch pipe is 4 inches  it isn't, but it's not too far off  and that of a 2 inch pipe is 2 inches, then the proportion is as 16 (the square of 4) is to 4 (the square of 2); therefore the 4 inch pipe has 4 times the area of the 2 inch.
To be more exact you would need to know the kind of pipe to which you are referring  e.g. sched. 80 CI, Type K copper, ABS... etc. etc. and then look up the actual inside diameters for those nominal sizes.Br. Jamie, osb
Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England0 
Formula
Q = A x V where Q = cubic feet per min. A = internal area of pipe in square feet and
V = velocity in feet per min. Q x 7.48 will give answer in gallons per min.
4" Sched. 40 has 3.77 times the area of 2" Sched. 40bob0
This discussion has been closed.
Categories
 All Categories
 85.1K THE MAIN WALL
 3K AC, Heat Pumps & Refrigeration
 55 Biomass
 424 Carbon Monoxide Awareness
 69 Chimneys & Flues
 1.9K Domestic Hot Water
 5.2K Gas Heating
 129 Geothermal
 160 IndoorAir Quality
 3.3K Oil Heating
 60 Pipe Deterioration
 868 Plumbing
 5.8K Radiant Heating
 375 Solar
 14.6K Strictly Steam
 3.2K Thermostats and Controls
 57 Water Quality
 48 Industry Classes
 87 Job Opportunities
 27 Recall Announcements