PVC Pipe Fitting Dimensions: What Schedule Suits Your Budget?
The terminology applied to explain PVC pipe fitting dimensions is often not intuitive, and the average person, untrained in plumbing or electrical work, will most likely have trouble working out just what the numbers on their pipe are referring to. Additionally, many people use technical terms such as ‘butt weld’ incorrectly to refer to certain methods which may in fact be more accurately described as heat fusion or something else entirely. Below I’ve outlined how PVC pipe fitting dimensions can be properly described, along with how welding procedures for metal and plastic differ in both practical terms and the names that they bear.
In North America, the term ‘Schedule’ is applied to describe the thickness of a pipe’s walls. Consequently, it actually has no bearing on either the inside or the outside diameter of the pipe, as you’ll often find claimed in online forums or on plumbing websites. The strongest-walled schedule available for home use is Schedule 80, which is piping so thick that you can walk on it without distorting its shape. It’s also capable of dealing with internal pressures of no less than 200 pounds per square inch (PSI) and temperatures of at least 75 degrees Fahrenheit.
Now, such heavy schedule PVC pipe fitting dimensions are actually considered to be complete overkill for the majority of home plumbing and domestic aquaculture applications. Indeed, schedule 40 piping is considered sufficient because, while, in small quantities, it is only a little more pricy than substantially thinner schedule 120 pipe (and a hell of a lot cheaper than steel pipe of a similar spec), it’s nonetheless rated for pressures of at least 160 PSI and a temperature of 73 degrees Fahrenheit. Now given that the highest pressure you’re likely to encounter with water coming off a city’s residential grid is about 150 PSI, one can see that there’s simply no point in having a higher spec of pipe, even if you decide to start refilling fire engines for a living. The external diameter exhibited by all of these pipes is, unless otherwise stated, always the same, and so you’ll never have a problem fitting a schedule 80 pipe onto a schedule 40 fitting, or vice versa.
Now, aside from confusions regarding PVC pipe fitting dimensions, a lot of people don’t seem to know the difference between butt welding and heat fusion. When you perform a butt weld, this is an instance where you’ve welded round or profile metal stock together, one end to another. Typically speaking, a machine is used to carry this process out. Initially, the two abutment sections or seams will be prepped and cleaned, placed in the welding machine and, once welded together, sanded down to improve their appearance and provide a smooth, seamless finish.
When one performs a similar process with plastic, this is correctly known as ‘heat fusion’. This involves taking two pieces of thermoplastic and heating the ends until sufficiently hot, then pressing them together and leaving them to cool. Once the pieces have cooled, they’ll have bonded in such a way that they’ve become indistinguishable from one another (provided, of course, that you chose to use two pieces of pipe of similar chemical composition and dimensions).
It’s now evident that plumbing enthusiasts tend to lack a proper understanding of such terminological distinctions, demonstrating the need for a centralized database that makes information regarding PVC pipe fitting dimensions and relevant welding techniques available to the general public.
