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large valve housing
Posted: Fri Aug 07, 2009 12:18 pm
by c11man
i am going to be making a 4inch piston and was wondering if using a wye instead of a tee would handle large recoil better. it would be used in a dual chamber setup
edit: a pressure rated wye costs aqbout $25 more than a tee so i was wondering if it would be worth the extra money
Posted: Fri Aug 07, 2009 1:15 pm
by dewey-1
Are looking at sch 40 pressure rated like these;
http://www.flexpvc.com/cart/agora.cgi?c ... s-45degree
I believe a better choice is a sch 80 tee;
http://www.bigbrandwater.com/pvc80tee10.html
A sch 80 wye is unrealistic price; ( CAUTION: sticker shock!)
http://www.bigbrandwater.com/pvcfittings422.html
Posted: Fri Aug 07, 2009 1:19 pm
by c11man
yes i am looking at those wyes. i dont want a sch 80tee because its more expensive and i would need two. a wye would let me use a cheeper tee along with it
btw that flexpvc link doesnt work but i know what you are talking about
Posted: Fri Aug 07, 2009 1:41 pm
by dewey-1
A sch 80 tee fitting will be much stronger than a sch 40 wye.
That is if you are looking for durability and safety.
Remember that fittings take the most stress compared to the pipe, whether that be recoil or just normal abuse.
Posted: Fri Aug 07, 2009 1:51 pm
by c11man
this is for a repair and the two sch 40 tees heald up until a dwv fitting (didnt know about it) gave way and took a junk of the tee with it. so i figured while i have to repair it why not make it better. and the wye would transer the recoil that normaly tryies to shear the pipe between the bottom of the tee and chamber into a straight force.
Posted: Fri Aug 07, 2009 2:22 pm
by King_TaTer
I saw in another thread that your cannon broke.
With that in mind go for SCH 80. It also depends on what configuration the Wye is in as well.
Posted: Fri Aug 07, 2009 2:43 pm
by c11man
the cannon did not break because the tee was sch 40!
it broke because the bushing was dwv and i missed it when i built it. the wye would have the angled socket facing backwards
Posted: Fri Aug 07, 2009 3:52 pm
by ralphd
If it's shock you are worried about then try a better bumper for the piston. I was about to build a 4 inch until I received the "T". It's huge.
Posted: Fri Aug 07, 2009 4:02 pm
by c11man
its not from a bumper! my bumper is good and i have a quite light piston. and remember the front blew out, not the back
so far i have had no imput as to if buying the wye is worth it.
Posted: Sat Aug 08, 2009 11:13 am
by c11man
sorry for double but i didnt think this needed a new topic. i found a sch 80 tee accualy cheeper than a wye. but i am worried that the id of the tee is going to be smaller than the 4inch pipe. do i have to get a peice of sch 80 pipe or what?
Posted: Sat Aug 08, 2009 12:11 pm
by dewey-1
The pipe wall is is .106 inch nominal difference between sch 80 and sch 40.
That is why I suggested a sch 80 tee originally and posted links.
What was wrong with using my advice?
I guess what is the major concern? Flow restriction or what?
I would personally feel much safer with sch 80 in such large diameters.
I refer to large as over 2 inches.
Posted: Sat Aug 08, 2009 1:54 pm
by c11man
major concern is that a piston that fits in a 4inch sch 40 pipe will not be able to slide through the tee inorder to seal on the barrel.
i feel safe with sch 40 up to 100psi in 4inch if i built it correctly and solvent welded properly. also i only use fresh pipe, no old pipe
Posted: Sat Aug 08, 2009 3:08 pm
by King_TaTer
Why would a SCH 40 tee ID be different than SCH 80 tee ID? They are both meant to accept either SCH 40 80 or 120 pipe. In pipe, ID's change. In fittings, OD's change.
Posted: Sat Aug 08, 2009 4:06 pm
by dewey-1
c11man wrote:major concern is that a piston that fits in a 4inch sch 40 pipe will not be able to slide through the tee inorder to seal on the barrel.
Now I think I understand your dilemma and what you are saying.
What you are saying is; with sch 40 pipe in a sch 80 tee, your piston is inside the pipe but when piston is slid towards barrel side of tee, it hits the inside stops or inside body of the tee.
This appears to be a slight difference with some different manufacturers.
There is a difference between Spears and Charlotte Pipe.
Do you have sch80 tee already and what brand is it?
If it is Spears, you should be OK with sch 40 in a sch 80 tee.
I am going by their CAD drawings.
Are you using a currently built piston or do you plan on a new one using sch 80 pipe?
The simplest solution, if you have this problem is to use sch80 pipe
Posted: Sat Aug 08, 2009 5:06 pm
by c11man
no i do not have the tee already. if the new cheeper site that i found has a wye for $30 i will get that but otherwise i will get the tee. i do already have a piston but i guess i could remake it