Mech/Elec ALS Lesson Seven - Water Supply And Drainage Systems: Materials and Methods - Steel, Copper & Plastics

topics:
Materials and Methods
Steel
Copper
Plastic


Mat. & Meth.
Many materials have been used for piping, even lead in the past because it was so easily malleable(bendable).

Steel
Untreated steel used to be called black iron due to its color, it easily rusted and was quickly replaced with galvanized steel pipe which has a thin layer of zinc bonded to the surface making it fairly rust-resistant.
Wall thicknesses were standardized by schedules, schedule 40 is the most common.
Steel pipe is typically mechanically joined by threading and collars.


Copper
Often used for supply and considered the best for this use.
Does not rust and is corrosion resistant, oxidation builds up a thin film which protects the copper.
Wall thicknesses are typically less than in other materials.
Three categories:
Type K (thickest walls)
Type L (Medium walls)
Type M (thinnest walls)
Most commonly used per MEEB & Archiflash is Type L.

Joining by a form of soldering called sweating.
Flux is applied to surfaces to be bonded, sections are heated so that flux melts, then pieces are put together having sleeves or elbows that fit over one another.
when cooled, the pipes are structurally joined and completely sealed.
Process easily reversed by reheating.


Plastic
Major competitor for copper pipe.
Two types are PVC & ABS
PVC used for supply, white with blue lettering
ABS used for drainage, larger, black, with white lettering

Does not corrode but deteriorates when exposed to ultraviolet light.
Do not expose above ground or outside walls.

Joining with sleeves using solvents or cements
Prime surface, let dry
apply cement or solvent
slide joint together.
process is NOT reversible.
Changes are made by cutting and replacing.