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 2343 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 The thread may already be out of date.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 4 posts

Saturday, May 3rd 2008, 4:34am

by drpete

Agree with wetboots. do your bucket test out of the 1 1/4" mainline and youll get your answer.

Thursday, May 1st 2008, 7:45am

by HooKooDooKu

One of the considerations in sizing pipe is that you want to observe the 5 feet per second speed limit. If water is allowed to flow faster than that, you increase risks of water hammer and damage to the plumbing. This is because kinetic energy quadruples as speed doubles.

This 5fps speed limit is where you are getting the number 23GPM for a 1-1/4 Sch40 PVC mainline. If you attempt to force more than 23GPM through a 1-1/4 mainline, you will be violating the 5fps speed-limit.

But just because there is a speed-limit doesn't mean your system can move that fast. As a ridiculous example, if your mainline pipe was 500' long and you had a static pressure of 10psi, there is no way in %#!! you are going to get 23GPM moving through that pipe.

So like Wet_Boots says, you've got to design for what your plumbing can produce, not the maximum allowed by "law".

Thursday, May 1st 2008, 7:22am

by Wet_Boots

Check the flow from your actual mainline plumbing, and design to fit.

Thursday, May 1st 2008, 12:51am

by turtleboy

Designing my first system and have a question about my gpm

i have a question on my system that I am desinging. I have been using the Jess Stryker irrigation tutorial on the web and I have gotten as far as setting up the zones and determining how many heads to put on my zones. I have a 1 1/4 mainline coming into my valves and per the tutorial I could use a GPM of 23 becasue of this. However when I checked the flow out of a hose bib I only had 10 GPM. My question is would I be safe using the 23 GPM for my head and zone placement or should I fall back on the 10 GPM to be safe? I am installing a whole new system so I will be buying all new valves. I just don't want to spend more than I have to.

One more thing. Does anyone like a particular in line valve over the others? I was looking at the hunter hpv-100gs but not sure if that is overkill or a good one for a smallish yard. How does the quality stack up to others? Any help would be appreciated.