PVC (polyvinyl chloride) pipes are widely used in construction, water supply and drainage, rainwater drainage and other fields due to their advantages such as lightness, corrosion resistance and simple construction. Among the many types of PVC pipes, SDR 35 pipes are a common specification and are widely used in building drainage systems. Understanding PVC sdr 35 pipe sizes, characteristics and applications can help designers choose suitable pipes in projects to ensure the reliability and safety of the system.
What is SDR 35 pipe?
SDR (Standard Dimension Ratio) is a standard used for pipe size design. SDR 35 means that the pipe size ratio is 35, which means that the ratio of the outer diameter to the wall thickness of the pipe is 35. The smaller the SDR value, the thicker the pipe wall thickness is, and the greater the pressure bearing capacity and strength of the pipe; the larger the SDR value, the thinner the pipe wall is, which is suitable for low pressure environments.
SDR 35 pipes are usually used in low-pressure drainage, rainwater drainage and sewage drainage systems. Its wall thickness design is suitable for bearing medium-intensity soil loads and has a certain resistance to external impact forces. Therefore, SDR 35 drain pipe is a commonly used pipe in drainage systems.
PVC sdr 35 pipe sizes
PVC sdr 35 pipe sizes standards involve outer diameter (OD) and wall thickness (the unit of wall thickness is usually millimeters). The following is a table of common PVC SDR 35 pipe sizes:
| De（mm） | Wall thickness（mm） | DN（mm） |
| 110 | 3.1 | 103.8 |
| 160 | 4.6 | 150.8 |
| 200 | 5.8 | 188.4 |
| 250 | 7.3 | 235.4 |
| 315 | 9.1 | 296.8 |
| 400 | 11.6 | 377.4 |
The table above lists the common outer diameter, wall thickness and inner diameter of PVC SDR 35 pipes. It should be noted that as the outer diameter of the pipe increases, the wall thickness of the pipe also increases accordingly to ensure that the pipe can withstand greater external loads and a certain internal pressure.
Features of PVC SDR 35 pipes
Good corrosion resistance
PVC material itself has good corrosion resistance and can effectively resist the erosion of most chemical substances. Therefore, SDR 35 pipes are suitable for pipe systems such as rainwater discharge and sewage discharge, which can ensure long-term use without corrosion.
Light weight and convenient installation
PVC pipes have a lower density and lighter weight, making transportation, handling and construction more convenient. Compared with pipes made of other materials, PVC pipes reduce labor intensity during installation, have a shorter construction period, and save labor costs.
Strong UV resistance
PVC pipes have strong UV resistance and are suitable for outdoor underground laying. Even if they are exposed to sunlight for a long time, the performance of the pipes is not easily affected.
Highly economical
The production process of PVC SDR 35 pipes is mature and the material cost is relatively low. Therefore, in the construction process, the overall cost of choosing this type of pipe is relatively economical, especially suitable for large-scale building drainage and municipal engineering projects.
Moderate pressure bearing capacity
The wall thickness design of SDR 35 pipes makes it suitable for bearing medium-intensity external loads. Although its pressure tolerance is not as good as pipes with lower SDR values, its performance is fully sufficient for most low-pressure drainage systems.
Applications
PVC SDR 35 pipes are mainly used in low-pressure drainage systems and water supply and drainage projects, and have a wide range of applications, as follows:
Building drainage systems
PVC SDR 35 pipes are widely used in drainage pipes, wastewater pipes and rainwater pipes in residential, commercial and industrial buildings. Its light weight and corrosion resistance make installation more convenient, and at the same time adapt to the low pipe pressure requirements in building drainage systems.
Sewage discharge system
SDR 35 pipes are widely used in sewage pipes, especially in urban sewers, sewage treatment plants and residential sewage pipe networks. Its corrosion resistance and good mechanical strength enable it to effectively cope with sewage erosion and external soil pressure.
Rainwater drainage system
In rainwater pipe systems, PVC SDR 35 pipes are widely used in urban drainage, underground drainage and flood drainage systems due to their good impact resistance and low cost. The outer diameter and wall thickness of the pipe can withstand general soil loads and are not prone to deformation.
Agricultural irrigation system
SDR 35 pipes are also commonly used in agricultural irrigation systems, especially in relatively flat areas, to transport irrigation water. Its corrosion resistance ensures the stability of the pipes in long-term use.
Industrial use
In addition to common areas such as drainage and rainwater, PVC SDR 35 pipes are also used in some light industrial pipes, such as chemical transportation and gas pipelines. Its good chemical resistance and cost-effectiveness make it also applicable in certain industrial environments.
Installation and Maintenance
Installation Requirements
The installation of PVC SDR 35 pipes should follow relevant industry standards and construction specifications. During the installation process, it is necessary to ensure that the joints of the pipes are well sealed to avoid leakage. At the same time, the buried depth of the pipes should be reasonably designed according to the soil type and external load to ensure that the pipes can operate stably.
Maintenance Recommendations
PVC pipes are relatively simple to maintain due to their strong corrosion resistance. However, during long-term use, the connection parts of the pipes should be checked regularly to prevent loosening or rupture of the joints due to aging or external forces.
PVC SDR 35 pipes are widely used in building drainage, sewage discharge, rainwater discharge and other fields due to their excellent performance, moderate size, economical cost and convenient installation methods. Understanding its size standards and usage characteristics will help engineering designers choose the most appropriate pipe specifications to ensure the quality of the project and the reliability of the system. With the continuous development of modern urban construction and infrastructure projects, PVC SDR 35 pipes will continue to play an important role in many fields.
