About Schedule 80 PVC Fittings
Spears schedule 80 PVC pipe fittings are the thicker-wall, heavier-duty version of the Sch 40 fittings, intended mostly for agricultural, commercial, industrial and irrigation liquid handling applications.
These fittings are capable of handling liquids up to 140°F and can withstand pressures much higher than standard Sch 40 PVC. They are installed in a manner similar to any other PVC fitting - the socket and spigot connections are glued using compatible PVC cement and primer, while threaded connections (MIP & FIP) are secured using appropriate thread sealant.
Understanding PVC fitting connections:
Sch 80 PVC fittings are available with either cement weld (glue) or threaded connections.
Cement weld, or standard glue-on connections - are of (2) types only -
Socket (sometimes also called Hub or Slip), which is the female end of the fitting into which the pipe is glued; and
Spigot, which is the same size as the PVC pipe itself and which glues into the socket connection (valve, fitting or outlet). Cement weld method utilizes familiar PVC cement and primer (heavy-body cement is often recommended over standard or medium-body one).
Threaded connections are, likewise, of (2) types only -
Male Threaded (also called MIP - Male Iron Pipe or MNPT - Male National Pipe Thread) and
Female Threaded (also called FIP - Female Iron Pipe or FNPT - Female National Pipe Thread). The male end is connected into the female end with wrench and the threads are sealed with thread sealant paste (but not PTFE tape).
Frequently Asked Questions:
Q: What is main difference between Schedule 80 and Sch 40 PVC fittings ?
A: The main difference is thicker fitting walls, allowing for higher pressure applications. Sch 80 PVC fittings are also commonly grey in color, to differentiate between them and Sch 40 fittings (which are white).
Q: Could Sch 40 and Sch 80 PVC pipe and fittings be used together ?
A: Yes, the ID (inside diameter) of the fittings (socket/hub specifically) are the same for Sch 40 and Sch 80. Similarly, the OD (outside diameter) of the pipes are the same. The only difference is wall thickness. However, when combined together, the pressure rating of the whole assembly will be per Sch 40 specifications, since such components have thinner walls.
Q: What does SR (special reinforced) mean in a PVC fitting?
A: Special reinforced PVC fittings have a stainless steel band around the female threaded (FIP/FPT/FNPT) portion of the fitting, offering a superior resistance to cracking which is often the result of over-tightening. These fittings are ideal for installations requiring high reliability, especially where vibrations are present and also present a simple solution when there's no means to control the torque of the wrench used to connect the threaded pipe.
Q: Are these fittings approved for potable water use?
A: They are, however they are not intended for distribution of potable hot & cold water in residential applications.
Q: What are the temperature and pressure ratings of Sch 80 PVC fittings?
A: The maximum liquid temperature is 140°F. As for the pressure – it varies depending on the pipe/fitting size and liquid temperature. See any product listing and click on the “Literature” tab for detailed information on pressure & temperature ratings.
Q: What kind of glue/cement/primer should I use for Schedule 80 PVC fittings?
A: For sizes up to 4", medium body cement could be suitable (varies by manufacturer, check compatibility first), but more often, heavy-body PVC cement is the recommended option.
