Plastic pipes or PVC pipes are best choice for any types of plumbing.
Both PVC-O and PVC-U have the same chemical make-up, thus it should come as no surprise that their overall qualities are of comparable too.
Plastic pipes introduction
Plastic made pipes are highly practical.
Polyvinyl chloride is a thermoplastic material that consists of PVC resin that has been compounded with variable proportions of stabilizers, lubricants, fillers, pigments, plasticizers, and processing aids.
PVC is a material that can be molded into almost any shape.
Various compounds consisting of these components have been produced in order to attain particular sets of qualities for a variety of different uses.
PVC resin is the primary component of each compound, notwithstanding this fact.
In the field of organic chemistry, the name "PVC" refers to "poly (vinyl chloride)," which describes the substance as "a polymer," or chained molecules of vinyl chloride.
In most written material, the brackets are not utilized, and the name of the material is typically reduced to PVC.
In the instances where a particular kind of PVC pipe is being discussed, that kind of pipe will be specifically named, as will be described in more depth below.
In the context of a more general discussion, the phrase "PVC pipes" will be used to refer to the full range of PVC pipe pressure materials that Vinidex has available to purchase.
- Several Distinct Varieties of Polyvinyl Chloride
Those PVC compounds with the fewest number of compounding ingredients and the fewest amount of plasticizers also have the fewest number of compounding ingredients.
Types of plastic pipes
The following table provides an overview of the general characteristics of PVC compounds that are utilized in the production of pipe.
The numbers that are provided here are for standard, unaltered formulas that make use of K67 PVC resin, unless otherwise specified.
A few figures for other types of pipe materials are displayed below for comparison.
The properties of thermoplastics are susceptible to large variations with temperature, and the relevant temperature range is stated whenever it is applicable.
The application of stress for an extended period of time can have an effect on mechanical characteristics, which should more accurately be characterized by creep functions.
In the area of this manual devoted to design, you will find additional data that is specifically relevant to pipe applications.
Users are encouraged to get in touch with our Technical Department if they have data that falls beyond the conditions that are specified.
Plastic pipes used in plumbing
Plastic pipes have proven much more resistance compared to metal in plumbing.
Because of creep, pipes that are subjected to higher strains will fail in a shorter amount of time compared to pipes that are subjected to lower loads.
This is a result of creep.
For pressure pipe applications, extended life is a key requirement.
Because of this, it is essential that pipes be built to function at wall stresses that will allow for extended service lives to be accomplished.
In order to determine the qualities over a long period of time, a large number of test specimens are examined in pipe form until they burst.
After that, each of these individual data points is plotted on a graph, and a regression analysis is carried out on the data.
Extrapolating the results of a linear regression analysis allows one to determine the 97.5% lower prediction limit failure stress at the design point.
This stress must be greater than a minimum needed stress (MRS).
The MRS is then multiplied by a safety factor to provide a maximum operating stress for the pipe material.
This value is then used to size pipes for a variety of pressure ratings.
The ISO design point of 50 years, which is equivalent to 438,000 hours, is utilized throughout in Europe and Australasia.
The design milestone of 100,000 hours has traditionally been utilized in countries of the North American continent.
This design point is very random, and it should not be taken as an indication of the PVC pipe's anticipated service life in any capacity.
Traditionally, the stress regression line is displayed on logarithmic axes, displaying the circumferential or hoop stress versus time to rupture.
Types of plastic pipes in plumbing
The types of design for PVC and plastic pipes intended for using in applications involving pressure like plumbing requires the prediction of the pipes' long-term qualities as well as the use of a safety factor.
As is the case with every other aspect of engineering design, the amount of confidence in the ability to forecast performance is reflected in the magnitude of the safety factor.
The increased confidence in the predictable behavior of the materials of the new generation, PVC-M and PVC-O, has the advantage of making it possible to employ a lower factor of safety in the design process.
PVC-O and PVC-M pipes operate at a greater design stress than ordinary PVC-U pipes as a result of their reduced safety factor and, in the case of PVC-O, higher strength in the hoop direction.
This is due to the fact that PVC-O has a higher strength in the hoop direction.
Creep and Elasticity – The modulus of elasticity of PVC-O is up to 24 percent higher than that of ordinary PVC-U in the orientated direction, while the modulus of PVC-O is comparable to that of standard PVC-U in the other directions.
