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Technician1002
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Sat Jul 04, 2009 12:38 pm

jimmy101 wrote:
Technician1002 wrote:In the Cellular test cannon, for strength, it originally had a 2 inch schedule 40 female fitting and schedule 40 plug for strength. (they exist) It was brittle and the female fitting shattered on a shot. Good thing I was wearing good leather shoes. Bad bruise, but no cuts or broken toes.
You mean of course that;
1) SCH 40 cleanouts exist, they are DWV only parts. The lower photo is a SCH 40 DWV cleanout.
2) In addition, there are SCH 40 pressure rated threaded components (the upper photo) that include threaded plugs.

I believe a "cleanout" is, by definition, a DWV only part since "cleanouts" aren't needed/used in PWS systems.

In other words, both of your photos are of SCH 40 parts. The lower one is a DWV cleanout and is not pressure rated. The upper one is a threaded fitting with plug that is pressure rated. Technically, the upper one isn't a "cleanout", though it could be used as one.

EDIT: Tagged the photos backwards.

The bottom photo is not of a Schedule 40 part. The telltale sign is the length of the threaded portion is about 1/2 the diameter. It has a short threaded section and short glue section.

Cleanout plug has a short threaded section.
Image

Schedule 40 plug has long threaded section.
Image

Schedule 40 parts have deep sockets both for threaded parts and glue joints.

The Schedule 40 female adapter can be used for connection to threaded pipe, pumps, valves, or sealed with a plug.
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Sun Jul 05, 2009 7:46 pm

Hmm, I don't think that is correct. I don't believe the schedule specifies the length of a threaded part or the length of a socket.

1. A 2" DWV SCH 40 Cleanout
2. A very short threaded male labelled as SCH 40

SCH 40 has nothing to do with the pressure rating of pipe or fittings. IIRC it also doesn't specify the depth of sockets. DWV only parts often have much shallower sockets but they are still SCH 40 parts.

I went through my parts boxes. Found several female threaded adaptors. Some are labeled SCH 40 and some are not. Nothing obviously different between any of them.

Found a couple male threaded "cleanouts". A couple examples of both styles shown in your photos. None of the male parts are labelled as SCH 40.

EDIT: Checked the Charlotte Pipe & Foundry Co. tech specifications for their SCH 40 DWV parts. (PDF is here.)
Looks to me like DWV only parts often have very shallow sockets and the male threaded cleanout with the raised square center is listed as a SCH 40 part.
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Technician1002
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Sun Jul 05, 2009 8:04 pm

jimmy101 wrote:Hmm, I don't think that is correct. I don't believe the schedule specifies the length of a threaded part or the length of a socket.

1. A 2" DWV SCH 40 Cleanout
2. A very short threaded male labelled as SCH 40

SCH 40 has nothing to do with the pressure rating of pipe or fittings. IIRC it also doesn't specify the depth of sockets. DWV only parts often have much shallower sockets but they are still SCH 40 parts.

I went through my parts boxes. Found several female threaded adaptors. Some are labeled SCH 40 and some are not. Nothing obviously different between any of them.

Found a couple male threaded "cleanouts". A couple examples of both styles shown in your photos. None of the male parts are labelled as SCH 40.

EDIT: Checked the Charlotte Pipe & Foundry Co. tech specifications for their SCH 40 DWV parts. (PDF is here.)
Looks to me like DWV only parts often have very shallow sockets and the male threaded cleanout with the raised square center is listed as a SCH 40 part.
May want to check the specification for Schedule 40. Often non schedule 40 parts get lumped in where they don't belong. White PVC doesn't make it meet the Schedule 40 Specification.

http://www.harvel.com/tech-specs-pvc-pipe-40.asp
* Denotes these sizes are dual marked as being in compliance with both ASTM D1785 (pressure pipe) and ASTM D2665 (drain, waste & vent pipe- DWV).
NOTE; Some DWV meet Schedule 40 requirements for wall thickness and pressure and may be dual labeled. Not all DWV is schedule 40.
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Fri Jul 10, 2009 12:28 pm

Technician1002 wrote:May want to check the specification for Schedule 40. Often non schedule 40 parts get lumped in where they don't belong. White PVC doesn't make it meet the Schedule 40 Specification.

http://www.harvel.com/tech-specs-pvc-pipe-40.asp
* Denotes these sizes are dual marked as being in compliance with both ASTM D1785 (pressure pipe) and ASTM D2665 (drain, waste & vent pipe- DWV).
NOTE; Some DWV meet Schedule 40 requirements for wall thickness and pressure and may be dual labeled. Not all DWV is schedule 40.
My reading of the spec:
All sizes of PVC Schedule 40 pipe shall be manufactured in strict accordance to the requirements of ASTM D1785 for physical dimensions and tolerances. PVC Sch 40 pipe sizes 1 1/4" through 24" diameters shall also meet the requirements of ASTM D2665 Standard Specification for PVC plastic drain, waste and vent (DWV) pipe and shall be dual marked as such. (http://www.harvel.com/downloads/spec-pv ... sch-40.pdf)
Digging up the ASTM D1785 spec, well, I don't have $43 for a copy. From the info at http://www.astm.org/Standards/D1785.htm SCH 40 appears to include the pressure rating (but I can't get what the rating actually is).

In practice, it appears to me that all pipe that matches the size specs (basically just the OD of pipe and ID of fittings) is labelled as SCH 40. That includes cell core PVC pipe that I doubt matches the pressure specs in ASTM D1785. I've even seen dust plugs (which definetly aren't pressure rated) labelled as SCH 40.

From http://www.ppfahome.org/pvc/faqpvc.html, it appears the SCH 40 applies to both pressure rated and non-pressure rated pipes. Solid PVC and cell core PVC. So, I don't see anything that says that SCH 40 has anything to do with a particular pressure rating. There are at least three ASTM-XXXX spec's that are applied to SCH 40 PVC pipe. The pipe only has to meet one of those ratings for the "SCH 40" marking. Heck, the pipe probably doesn't have to meet any of those ASTM-XXXX specs, if it has the right pipe OD and the right fitting ID then it probably falls within the umbrella of SCH 40.
What are the primary applications for PVC, and what are the standards?

1. Water Pipe:
* ASTM D1785, Sch 40 and 80 pipe (1/8" to 24" sizes)
* ASTM D2241, SDR pipe (SDR 13/5 to 64 - 1/8" to 36" sizes)
* AWWA C900, Water mains 4" through 36"
* AWWA C905, Water transmission pipe 14" through 36"
* AWWA C909, Molecularly Oriented Polyvinyl Chloride (PVCO) Pressure Pipe, 4" to 24" for Water Distribution

2. Drain, Waste & Vent Pipe:
* ASTM D2665, Sch 40 (Can be dual marked D1785)
* ASTM F891, Cellular core Sch 40, 1 1/4" through 12"
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