PVC Schedule 80 Buying Guide
Everything in this collection is Spears PVC Schedule 80, in sizes from 1/4 in. to 14 in. depending on the fitting. Schedule 80 is the choice when a line runs at higher pressure, hotter, or under more mechanical stress than Schedule 40 is rated for.
What Does Schedule 80 Mean?
Schedule refers to wall thickness, not outside diameter. A 2 in. Schedule 80 fitting has the same outside dimensions as a 2 in. Schedule 40 fitting but a thicker wall, which raises its pressure rating and its resistance to impact and mechanical stress. Because the wall is thicker, the internal bore is slightly smaller — worth accounting for on long runs where flow rate matters. Schedule 80 PVC is normally supplied in dark grey so it can be told apart from white Schedule 40 on site.
Pressure ratings vary by size and fitting type, and drop as temperature rises. Check the rating for your specific size and service temperature on the product page or the Spears data sheet before specifying.
Choosing the Right Fitting Type
- Elbows — 90, 45 and 22 degree, for changing direction without adding an extra joint.
- Tees, reducer tees, crosses and wyes — branch or split a line without cutting the main run; reducer tees step the branch down to a smaller size.
- Couplings and reducing couplings — join two straight pipe ends permanently, or step between two sizes.
- Unions — do a coupling's job but can be taken apart for maintenance. Available with EPDM or FKM seals, including the Union 2000 series.
- Adapters and reducing bushings — transition between socket, male thread and female thread, or between sizes, so one connection type does not force a redesign.
- Flanges — socket, threaded, blind, and Vanstone in socket, threaded and spigot. Vanstone flanges rotate to line up bolt holes, which makes tank and pump connections much easier to align.
- Caps and plugs — close off a line permanently or for testing; caps fit over a pipe end, plugs fit into a fitting.
Solvent Weld or Threaded?
Most fittings here come in socket (solvent weld), threaded, or a socket-by-threaded combination, and some in spigot. Solvent weld makes a permanent, leak-resistant joint and is the default for buried or hard-to-reach runs. Threaded joints can be taken apart, which matters anywhere a pump, valve or instrument may need removing.
Solvent-weld joints need a PVC-rated primer and cement, applied in that order — skipping primer is a common cause of joint failure. Threaded PVC should be sealed with PTFE tape or a sealant rated for plastic, and tightened by hand plus a fraction of a turn; plastic threads strip if torqued like metal. Follow the cement manufacturer's cure times before pressurising.
Chemical and Temperature Service
PVC resists many acids, bases and salts, which is why Schedule 80 is common in chemical processing, water and wastewater treatment, cooling water and irrigation. Resistance depends on the specific chemical, its concentration and the temperature, so for anything beyond water or dilute-chemical service confirm compatibility for your fluid before choosing PVC over CPVC or another material.
PVC Schedule 80 FAQ
What does Schedule 80 mean on a PVC fitting?
It is a wall-thickness classification, not a size. At the same nominal size, Schedule 80 has a thicker wall than Schedule 40 and a higher pressure rating, and is normally dark grey rather than white.
What is the difference between Schedule 40 and Schedule 80 PVC fittings?
Same outside dimensions, thicker wall on Schedule 80, higher pressure rating, slightly smaller internal bore, and a colour difference so they are easy to tell apart on site.
Are Schedule 80 PVC fittings chemical resistant?
PVC resists a wide range of acids, bases and salts, but resistance depends on the specific chemical, concentration and temperature. Confirm compatibility for your fluid before specifying, particularly beyond typical water treatment or irrigation service.
Do I need special cement for Schedule 80 PVC?
You need a PVC-rated primer and solvent cement, the same family used for Schedule 40. The primer step matters: skipping it is a common cause of joint failure.
Can I mix threaded and solvent-weld fittings in the same system?
Yes, using an adapter or reducing bushing to transition between the two. Do not combine a threaded and a solvent-weld connection on the same joint, and do not over-torque threaded plastic.
What is a Vanstone flange?
A flange with a rotating ring, so the bolt holes can be turned to line up with the mating flange instead of having to rotate the pipe. Carried here in socket, threaded and spigot up to 12 in.
What sizes are available?
From 1/4 in. up to 14 in. depending on the fitting — couplings reach 14 in., while elbows, tees, bushings, caps and flanges reach 12 in. Use the size filter above for current in-stock options.
Need Help Specifying?
Alsco Industrial has specialised in corrosion-resistant fluid handling since 1983. If you are unsure whether Schedule 80 PVC suits your pressure, temperature or chemical, fill out our Contact Us form and our team will help you specify it. You can also browse PVC pipe, valves, and cements and accessories to complete the system.
