PVC-U disk valve dn80 wafer design

This type of fittings often causes controversy among installers - some say that cast iron is better for drainage systems, others insist on uPVC because of its chemical resistance. Personally, I often use Shandong Linyao Intelligent Agriculture Technology in projectsuPVC dn80, especially when it comes to feeding fertilizers with aggressive additives.

Features of wafer design

The wafer design saves up to 40% of installation space - critical in wells with pumping equipment. But there is a nuance: when tightening between the flanges, the seal is sometimes deformed if you overdo it with the tightening torque. I checked it at a facility in the Krasnodar Territory - three valves had to be replaced due to leaks for this reason.

uPVC butterfly valves can withstand up to 10 bar at temperatures up to 45°C, but in drip irrigation systems it is better not to exceed 6-7 bar. I remember an incident at an intellectual park project in the Rostov region, where pressure surges broke the connection exactly at the installation site of the butterfly valve - the problem was the wrong choice of pressure class.

Forwafer designIt is important to maintain alignment - even 2-3 mm of misalignment leads to premature wear of the disk. We at Shandong Lingyao always use centering pins during installation, although many contractors neglect this.

Practice of application in agricultural projects

In water and fertilizer integration systems, dn80 valves operate in flow switching areas. It is important to place them after the filters - solid particles from open reservoirs quickly damage the rotating mechanism. Tested at five sites - where prefiltration was not installed, the valves required replacement after 2-3 seasons.

During installation in the field, I noticed that polypropylene flanges put less load on the body compared to metal ones. But for ground-based installation, metal is still better - there is less risk of damage during maintenance.

In automation projects from Shandong Lingyao, we equip these gates with remote control electric drives. An important point is that you need to take into account the inertia of rotation of the disk when programming the controller, otherwise water hammers are possible.

Typical installation errors

The most common is installing a valve without pipeline support. With thermal expansion of uPVC, the entire load goes to the flange connections. Once I had to redo a site in a greenhouse complex near Voronezh, where a pipe cracked because of this.

They also forget about the direction of flow - there is an arrow on the body, but many installers do not pay attention. As a result, the shutter creates additional resistance, and in some modes, vibration.

When soldering uPVC flanges, it is important not to overheat the joint area - the polymer loses strength. We have developed a special technology in Shandong Lingyao with temperature-controlled soldering irons, but most installers still work with conventional equipment.

Comparison with other materials

Polypropylene is cheaper, but is not suitable for systems with fertilizers - it is destroyed by some types of ammonium nitrate. uPVC can withstand almost all common agrochemicals, which is confirmed by tests in our laboratories.

Cast iron valves are mechanically more reliable, but require cathodic protection against corrosion in the ground. For underground installation in drainage systems, we sometimes use them, but with mandatory waterproofing.

Steel analogues can withstand greater pressure, but for most agricultural systems this is excessive. In addition, the cost of a steel gate is 2-3 times higher with a comparable service life under land reclamation conditions.

Maintenance Recommendations

Once a season you need to check the condition of the seals - in systems with suspended fertilizers they wear out faster. I noticed that EPDM rubber lasts longer than nitrile rubber in such conditions.

When preserving the system for the winter, be sure to turn the disc several times - otherwise it may stick to the seat. This is especially true for regions with frost, where moisture remains in the pipes.

In Shandong Lingyao projects, we always install inspection pipes before and after the valves - this allows diagnostics to be carried out without disassembling the entire line. It's a small thing, but it saves hours of work during maintenance.

OveralluPVC butterfly valve dn80– a good solution for most agricultural systems, if you approach the installation correctly and take into account the specifics of operation. The main thing is not to skimp on the quality of flange connections and to follow the installation technology.