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PurpHaze
11-20-2006, 12:21 PM
In doing a little research for ductile iron fittings and joint restraint fittings for push-together pipe I came across the following explaining the difference between ductile iron and cast iron. Maybe nobody else will find it interesting but we're going to these fittings more and more in our area with the increased use of push-together pipe and HDPE pipe for larger pipe sizes.

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Cast iron is a generic name for any high carbon molten iron poured as a casting. When used to refer to pipe, cast iron (sometimes called gray iron) is a specific type in which the free graphite (Carbon) is in the shape of flakes. Cast Iron pipe were introduced into the United States in 1817.

Ductile Iron is a specific type of cast iron in which the free graphite is in the shape of nodules or spheroids. (Other names for ductile iron are nodular iron or spheroidal graphite iron.) Ductile Iron Pipe were introduced to the market in 1955.

Although nearly identical chemically, the two irons are quite different metallurgically. The now obsolete standard for Cast Iron Pipe (ANSI/AWWA A21.6/C106) required an iron strength of 18/40 (18,000 psi Bursting Tensile Resistance and 40,000 psi Ring Modulus of Rupture.) Although tensile testing was not a requirement of this standard, a tensile test of gray cast iron pipe would give a test result of approximately 20,000 psi Ultimate Tensile Strength, with no measurable Yield Strength or Elongation.

The current standard for Ductile Iron Pipe (ANSI/AWWA A21.51/C151) requires a minimum grade of 60-42-10 (60,000 psi Ultimate Tensile Strength, 42,000 psi Yield Strength, and 10% Elongation.) In addition, Ductile Iron Pipe manufactured under this standard are required to meet a minimum of 7 ft lbs impact resistance by the Charpy test. (Compare Gray Iron Pipe with an impact resistance of approximately 2 ft lbs or less.)

The difference in the physical properties of these two materials is attributable almost entirely to the difference in the shape of the free graphite. The shape of the graphite is determined at the instant of solidification and is made nodular by the addition of magnesium to the molten iron bath. Although Cast Iron was the best engineering material available for pipe production for nearly five hundred years, the development of Ductile Iron Pipe provides a far superior product.

BSME
11-20-2006, 02:34 PM
you're right....

nobody else did find that interesting :sleeping:

jerryrwm
11-20-2006, 03:53 PM
Wow...I'm impressed. You guys on that left coast sure have a lot of time on your hands.:dizzy:

PurpHaze
11-20-2006, 05:19 PM
you're right....

nobody else did find that interesting :sleeping:

Guess if all you work with is 1" PVC or poly then there'd be no reason to even attempt to understand ductile iron fittings, joint restraint fittings, knuckle joints, HDPE pipe, mechanical joints, etc. :nono:

PurpHaze
11-20-2006, 05:21 PM
Wow...I'm impressed. You guys on that left coast sure have a lot of time on your hands.:dizzy:

By taking 2-1/2 vacation days off I end up with nine straight days off.:)

DanaMac
11-20-2006, 05:40 PM
By taking 2-1/2 vacation days off I end up with nine straight days off.:)

That almost beats my upcoming 3-4 months of vacation!!

Mr. Vern
11-20-2006, 05:55 PM
I found it interesting alright. I'm just wondering what useful information had to be displaced from my brain in order to make room for it.

Anyone seen my car keys?LOL

PurpHaze
11-20-2006, 06:12 PM
That almost beats my upcoming 3-4 months of vacation!!

Guess we're about even then. Between vacation time (4 weeks/year), holidays and comp time it's a wash. I just spread mine out over the year. Oh... and I very rarely have to work weekends during the height of the season unlike many others on this forum. :)

DanaMac
11-20-2006, 07:02 PM
Yeah but I also took off mid -August through Oct 1. Heck, I'd be pretty well off if I actually worked 12 months each year. April, May and June I keep thinking "Look forward to the winter, look forward to the winter".

PurpHaze
11-20-2006, 08:06 PM
And isn't that same time when you're running around chasing your tail and being a real biatch??? :laugh:

Dirty Water
11-20-2006, 08:16 PM
Hayes, why not go to C900 plastic pipe at these sizes instead of iron?

All the major water companies in my area have switched, its good stuff.

PurpHaze
11-20-2006, 08:44 PM
Hayes, why not go to C900 plastic pipe at these sizes instead of iron?

We don't use DI pipe... just DI joint restraint fittings like the HARCO ones. Saves having to pour a bunch of thrust blocks.

PurpHaze
11-20-2006, 08:48 PM
Here's what got me started on the DI. :laugh:

http://www.harcofittings.com/products/restraints.html

DanaMac
11-20-2006, 09:01 PM
And isn't that same time when you're running around chasing your tail and being a real biatch??? :laugh:

April, May and June is when I am Biatch. August and September things are slow and I go fishing in Montana :)

Dirty Water
11-20-2006, 09:16 PM
We don't use DI pipe... just DI joint restraint fittings like the HARCO ones. Saves having to pour a bunch of thrust blocks.

I'll be running a new 4" main in the spring on a commercial job (Gonna use the new excavator wee!), still up in the air of we are going to use gasket pipe or glue, I've never done a large gasketed main, all the other 4" stuff I've done is glue and its a bit of a PITA.

Someone was telling me that you don't need to thrust block glued pipe, only gasketed, but we still thrust block every change of direction ( Butt the pipe against native soil and pour concrete around the fitting).

Those thrustblock fittings are pretty nifty.

PurpHaze
11-20-2006, 09:40 PM
Someone was telling me that you don't need to thrust block glued pipe, only gasketed, but we still thrust block every change of direction ( Butt the pipe against native soil and pour concrete around the fitting).

I went to a Ewing seminar last week up in Clovis and the guy giving the thing stated the same. "Solvent weld connections (regardless of size) don't need thrust blocks."

We handle so much larger pipe that it just seems small to us. It's like anything else... the more you do the simpler it gets because you develop a comfort zone. Get a bigger applicator for larger pipe and it's just like glueing 1". :)

Dirty Water
11-20-2006, 09:47 PM
So whats your opinion Hayes? Thrust blocks or not?

jerryrwm
11-21-2006, 08:21 AM
Jon, If you put the gasket pipe in you'll wonder why you ever tried to mess with solvent weld pipe in the bigger sizes. Just get it lined up straight, put the 'puppy snot' on the gasket and pipe, and shove it home to the ring.

And as far as thrust blocks on solvent welded pipe, the guys telling you that you don't need it, damn sure aren't the guys that are going to be out there helping you make the repair if one of them bad boys comes apart. $6.00 woth of sak-krete is cheap enough insurance.

PurpHaze
11-21-2006, 10:29 AM
So whats your opinion Hayes? Thrust blocks or not?

If you go solvent weld and you're using that IPS glue that we discussed in an earlier thread that seems to be pretty much the same as the Plumb Tite we use I'd forego the thrust blocks. To tell you the truth, I've never had a 4" solvent weld fitting push out from lack of thrust blocks. Check your glue's set time and adhere to it by not moving joints, etc. until they've set up properly.

If you go gasketed pipe then you will need either thrust blocks or joint restraint fittings.

PurpHaze
11-21-2006, 10:37 AM
Jon, If you put the gasket pipe in you'll wonder why you ever tried to mess with solvent weld pipe in the bigger sizes. Just get it lined up straight, put the 'puppy snot' on the gasket and pipe, and shove it home to the ring.

We use "duck butter" and a bar at the end to ease pushing the pipe into bells.

And as far as thrust blocks on solvent welded pipe, the guys telling you that you don't need it, damn sure aren't the guys that are going to be out there helping you make the repair if one of them bad boys comes apart. $6.00 woth of sak-krete is cheap enough insurance.

Sorry... gotta disagree with you on this one. Use a good glue and primer and adhere to set times and there shouldn't be any problems. I've glued tens of thousands of feet of 4" pipe without problems.

jerryrwm
11-21-2006, 10:49 AM
Sorry... gotta disagree with you on this one. Use a good glue and primer and adhere to set times and there shouldn't be any problems. I've glued tens of thousands of feet of 4" pipe without problems.

It only takes one. I have made many solvent weld joints in the big stuff also. I prefer MJ fittings when doing repairs on the big stuff also, but that took a little learning over the years. And as for joints in 4", you are correct about the type of cement and the set times, etc. But the human factor comes into play and I can't and don't have the time to personnally make every connection in the line. So as a safe-guard against pipe creep and ground shift, I require thrust blocks on the turns and tees. It doesn't take much more time to cut out a concrete encased fitting than it does one without. Then there is always the situation where the original contractor used gasket pipe and solvent weld fittings. A little water hammer and things can get exciting.

JMO

ps. I would never, ever use 'duck butter' when there is a tub of 'puppy snot' available.

PurpHaze
11-21-2006, 11:13 AM
I prefer MJ fittings when doing repairs on the big stuff also, but that took a little learning over the years.

We use the Dresser/glue tee (etc) avenue of repairing the big stuff like I've shown in many pictures. It's quick and easy. The key to any large pipe repair is the digging part. You almost need some type of backhoe to get a big enough hole dug to handle the repairs.

And as for joints in 4", you are correct about the type of cement and the set times, etc. But the human factor comes into play and I can't and don't have the time to personnally make every connection in the line. So as a safe-guard against pipe creep and ground shift, I require thrust blocks on the turns and tees.

I fully understand this. However, I have at least four guys that work with us regularly that I have confidence in glueing the larger pipe. The "human factor" can be overcome via proper training and then having them do it initially under supervision.

It doesn't take much more time to cut out a concrete encased fitting than it does one without.

This depends. I've seen some thrust blocks that are a couple of yards of concrete. [JK]:laugh:

Again... The key is the excavating of the hole.

Then there is always the situation where the original contractor used gasket pipe and solvent weld fittings. A little water hammer and things can get exciting.

If it's a mixed installation then it must be treated like a gasketed system.

ps. I would never, ever use 'duck butter' when there is a tub of 'puppy snot' available.

Some older plumbers in our area refer to it as "whale sperm". :p

PurpHaze
11-21-2006, 11:22 AM
Jerry... check this out. Very interesting. :)

http://romacindustries.com/FJoint.html

Wet_Boots
11-21-2006, 11:59 AM
Keep this thread going, and you might create a Googlewhack (http://www.google.com/search?q=%22duck+butter%22+%22puppy+snot%22)

PurpHaze
11-21-2006, 12:15 PM
I think it could be related to the "knick-knack, paddy-whack" syndrome.

Dirty Water
11-21-2006, 07:47 PM
Up here, the guys call it Boy Butter, which is almost as bad as whale sperm :)

PurpHaze
11-21-2006, 09:06 PM
Is there a prison near Sequim???:p