AUTOMATIC and manual ceramic ball valves offer a cost-effective alternative to solenoid valves and provide better wear resistance. Various innovations mean that these valves are now suitable for a greater number of applications than ever before.
Lynette Morrey, Business Development Administrator at Allmech, South African manufacturer of boilers and supplier of water treatment components and the sole official agent in South Africa for Runxin water treatment systems, explains that Runxin’s patented ceramic ball valve is used in applications ranging from sewerage treatment plants to chemical plants, paper mills and irrigation systems. “They are safe to use with gasoline, compressed air, gas and most alkaline liquids and acids,” she says. “The ceramic valves are ideal for filtration and softener systems used in water treatment.”
They’re available in two-wire, three-wire and three-way (L-shape) variants from DN 15 – DN 50 threaded or glued fitting options. The ceramic rotary ball and seat is machined in such a way that no fluid or air will leak through the ball. It can withstand humid conditions and is corrosion and chemical resistant. “The ceramic ball valve can withstand far higher flow rates, water pressures up to 10 bars and temperatures up to 80°C,” Morrey says.
Time-controlled ball valves
“Time-controlled ball valves are great for automatic drainage, or irrigation that would need to happen at set times for set durations daily, or even for ensuring water for showers can supplied at certain times of day in change rooms,” says Morrey.
There are two options available. One is to control the valve by setting the duration of open and closed time, using a countdown timer. The other option is that the valve can be set to open and close at set times and for specific durations, from Monday to Sunday, with up to five settings (1 to 5 times) per day.
“There is an indicator light to show whether the valve is open or closed and if the power supply is off for some reason, the current setting will be saved automatically for three days,” says Morrey.
Valves with positional feedback function
“Many industrial processes, such as power generation, mining, food manufacturing and chemical manufacturing, use a series of ball valves, and could benefit from the positional feedback valves in these applications,” says Morrey. “This is an adjustable ball valve, with a TCN-02T Actuator.”
The degree and angle that the ball can be opened at can be determined by the PLC, and adjustments for flow, temperature and pressure can also be made.
Positional feedback valves allow for accurate regulating of exact angle that the ball valve opens and closes and avoid the inconvenience caused by mechanical positioning. They also reduce errors and generate an immediate alert if the ball valve is not operating correctly or is jammed. Furthermore, because they use standard connections, they are easily installed, adjusted or replaced. They can be mounted on a bracket for plastic or metal ball valves and are ideal for both indoor and outdoor use (although they require protection if exposed to extreme sunlight or weather conditions).
The position feedback signal ranges from 0-5V, while the controlling signal is 0.5V. The valve is DN25 size, with a female thread connection DC24V.
“Ensure the ball valve is resistant to the fluid or chemical it will be exposed to, and consider the quality of the water. Large particles (bigger than 0.2mm) or sediments in the water would require a pre-filtration system to avoid valve damage,” suggests Morrey. “Also remember that if the valve is opened up by an unauthorised technician, the manufacturer’s warranty will generally be voided.”
She suggests contacting a reputable valve supplier to undertake a site visit. “That’s what we do before we recommend the best solution and the correct ball valve for customers’ specific applications,” she says. “Our team is always available to offer assistance with troubleshooting and has undergone comprehensive technical training from Runxin. All ball valves we supply carry a one-year manufacturer’s warranty.”