You are not logged in.

Reply

Dear visitor, welcome to SPRINKLER TALK FORUM - You Got Questions, We've Got Answers. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.

Attention: The last reply to this post was 3017 days ago. The thread may already be out of date. Please consider creating a new thread.

Message information
Message
Settings
Automatically converts internet addresses into links by adding [url] and [/url] around them.
Smiley code in your message such as :) is automatically displayed as image.
You can use BBCode to format your message, if this option is enabled.
Security measure

Please enter the letters that are shown in the picture below (without spaces, and upper or lower case can be used).

The last 3 posts

Thursday, January 19th 2006, 4:31am

by Msddouglas

Thank you so much for your help!

Larry

Wednesday, January 18th 2006, 5:32pm

by big_gus

By extending your suction pipe and the decreased lake level you have decreased you total available pressure at your irrigation output two ways:


1) Depending on the diameter of your suction pipe and your flow rate, your additional pressure loss due to friction could be high. For example, if you are using 1" copper pipe at a flow rate of 10 gal/min, 100 ft of pipe would add an additional 3.7 psi of pressure loss. See this link for some great friction loss tables: http://www.irrigationtutorials.com/sprinkler09.htm
Please note that pipe friction is a beast, if your pipe has significant build up, or lots of fittings, your friction loss could be much greater depending on flow rate.


2) The formula for the pressure loss due to the decrease in lake level is:
(Change in Pressure) = (density of water) * (gravity) * (change in suction point elevation)
Given that you are on the plant earth and the water you are using is of normal density (no nuclear power plants nearby), plugging in the constants gives you:
P(psi) = 0.0362 * height (inches) or
P(psi) = 0.434 * height (ft)
Therefore if you lost 10 ft of elevation at your suction point, you would have an additional 4.3 psi of pressure loss.


If after you have done the math and you find that you still have plenty of pressure available in your system, then I would suggest you start to look for some sort of clog or flow restriction in your system. Clean your filter, etc....

Hope this is helpful!
-gus



Saturday, January 14th 2006, 9:17am

by Msddouglas

Lake Water Sprinker System

Our sprinkler system uses lake for it's water supply. The lake has gone down so far that we have extended our suction pipe over 100 ft. to reach the water. Is this the reason we've lost pressure to our sprinker heads? We were able to run 6-7 heads at a time, now we are only able to run (3) heads at a time. Thanks for your input.