For friends in engineering procurement, the selection of PVC drain pipes is definitely a "can't be wrong" job - if you choose a small one, the drainage will not be smooth and blocked; if you choose a thin one, it will break after a little pressure; if you choose a long one, you will have to find a large truck for transportation, and it will be troublesome to turn on the construction site. At this time, a clear PVC drain pipe specification and model table is the "universal dictionary" to solve these problems, helping you turn "choosing by feeling" into "choosing by data".

You have to understand several core parameters of PVC drain pipes first, otherwise reading the specification table is like reading a "book from heaven". The first is the pipe diameter, which is expressed by "nominal outer diameter (dn) " in the industry. The larger the number, the thicker the pipe. For example, DN50 is a pipe with an outer diameter of 50 mm. The second is the wall thickness, which directly determines the strength of the pipe. Under the same pipe diameter, the thicker the wall thickness, the more resistant it is. The third is the length, which is commonly available in 4 meters and 6 meters, which affects the transportation cost and construction efficiency. There are also pressure grades. Although PVC drainage pipes are mostly unpressurized drainage, scenes such as rainwater collection and underground garage drainage may require a little low pressure, which must be selected accordingly.

the following table, covering more than 90% of the common scenarios in the project, according to the selection of basic will not step on the pit:

- dn50: wall thickness 2.0mm (light)/2.5mm (heavy), length 4m/6m - suitable for kitchen sink, bathroom sink branch pipe, or balcony floor drain pipe, small water drainage just enough;

- dn75: wall thickness 2.3mm (light)/2.9mm (heavy) - thicker than dn50 circle, suitable for toilet toilet drain pipe, or small balcony rain pipe, can handle slightly larger water;

- dn110: wall thickness 3.2mm (light)/4.0mm (heavy) - this is the "main force" of indoor drainage, such as floor risers (from the top floor) The main pipe leading to the first floor), the main drain pipe from the bathroom to the downstairs, almost all residential projects are used;

- dn160: wall thickness 4.0mm (light)/5.0mm (heavy) - suitable for the courtyard drainage of the community, the rainwater collection pipe of the underground garage, or the main drain pipe of the low-rise commercial building, which can handle the water catchment of multiple households;

- dn200: wall thickness 5.0mm (light)/6.3mm (heavy) - used for the main road drainage of the community, the branch pipe of the municipal road, or the initial rainwater pipe of the industrial park, the drainage volume is larger;

- dn250: wall thickness 6.3mm (light)/7.8mm (heavy) - the drainage pipe of the large community, the production waste pipe of the factory, and the scene that needs to transport a lot of water for a long time;

- DN315: Wall thickness 7.8mm (light)/9.8mm (heavy) - the main drainage pipe of the municipal main road, the sewage main pipe of the industrial park, or the outlet pipe of the large rainwater pumping station is a "high flow player".

just looking at the table is not enough, you have to remember a few "tips" when purchasing:

First, the matching scene is not greedy - for example, the indoor branch pipe chooses DN50 on the line, there is no need to choose DN110, wasting money and taking up space; municipal main roads have to choose DN200 or more, otherwise the rainstorm will definitely accumulate water;

Second, check the wall thickness and don't be lazy - the national standard requires that the wall thickness deviation cannot exceed 10%, such as the heavy-duty pipe wall thickness of DN110 is 4.0mm. If you buy less than 3.5mm, it is easy to be stepped on;

Third, the length is selected to save trouble - although the 6-meter-long pipe is transported to find a larger car, but the number of splicing during construction is small and the efficiency is high; if the construction site is in the old city, the road is narrow and it is not easy to enter the cart, choose 4 meters;

Fourth, don't miss the pressure level - if it's a rain pipe in an underground garage, because you want to withstand the earth pressure above, you have to choose a low-pressure grade pipe, don't buy a pure pressure-free one, otherwise it may crack after a few years.

In fact, the procurement logic of PVC drainage pipes is very simple: don't choose "expensive" or "large", but choose "right". With this specification and model table, you don't need to read the thick standard manual, and you don't need to "break" the parameters with the supplier. You can directly find the corresponding model on the table according to the drainage requirements of the project - such as whether it is residential or municipal, whether it is branch or main pipe, and how much water is available.

Final reminder: Before purchasing, it is best to check the specification table with the design drawing to confirm whether the pipe diameter and wall thickness are consistent with the drawings. Avoid "buying the right table and choosing the wrong project". After all, the drainage system is the "blood vessel" of the project, and choosing the right PVC drain pipe can make the whole system "unobstructed".