These two pipes are just a standard. The most critical parameter is thickness. Schedule 80 is much thicker than Schedule 40 PVC pipe, and Sch 80 pipe is gray or dark gray in general. Sch 40 PVC pipe is white compared with the same period, and the thickness is thinner than Sch 80 PVC pipe.
So it is obvious from the comparison of the two parameters. Schedule 40 PVC pipe can be considered for home improvement or indoor decoration, while Schedule 80 PVC pipe is much stronger, so it can be considered for outdoor projects.
For more details you can refer our recent post in question 3,
According to the customers we serve, the length of most customer requirements is as follows:
3 Meters (9.84 ft)
6 Meters (19.69 ft)
12 Meters (39.37 ft, only for special project)
Reasonable length is convenient for long-distance transportation and installation. Normally, electrical pipes are loaded in containers when they are shipped abroad, and then delivered by sea. Even short-distance transportation requires the use of trucks. If it is too long, it is not easy to load and accidents are prone to occur. In addition, shorter pipes are also easy to install, because we also need multiple pipes in most cases during installation.
Considering most of buyer can learned about the basic information from the marking on conduit body,so we take an example as below,
Information to be marked on conduits:
a) The name of the manufacturer or responsible vendor, or a trademark, or other identifying symbol;
b) The nominal size;
c) The word ‘ELECTRICAL’, ‘HEAVY DUTY’ or ‘HD’;
d) Is marked with the letter ‘T’ . As per AS/NZS 2053 the standard requires that conduits suitable for use in direct sunlight be marked with the letter ‘T’
e) Be marked ‘Solar’.
f) Be marked above informations not exceeding 2m.
PVC, like other plastics, is often accompanied by many impurities after being eliminated and used, and it needs to be sorted before it can be recycled. The early physical recycling and burning recycling methods have been eliminated. The quality of the plastic materials recycled by the former is not good because it is difficult to sort. The latter is harmful to the environment because many harmful gases are released during the burn of PVC to pollute the environment. Therefore, at present, only chemical recycles methods can be used to do this. Chemical recycles can get higher quality recovery, but the cost is high.
We talked about this issue in our post as below,you can read our post in No.6 questions for more details.
PVC is made from fossil fuels, including natural gas. The production process also uses sodium chloride. Recycled PVC is broken down into small chips, impurities removed, and the product refined to make pure PVC. It can be recycled roughly seven times and has a lifespan of around 140 years.
For more information, refer to Wikipedia about Sustainability.