Valve is King

This article was adopted from ControlGlobal.com.

Predictive Maintenance Keeps Valves Humming

Without valves there would be no way to control either the flow or temperature of the fluid in a piping system. When treated like the essential devices that they are, valves will provide a higher level of system performance for a longer amount of time.

When specifying a valve for your application, Rick Plummer of Spirax Sarco recommends asking several questions. Can the valve:

• Be maintained and restored to duty quickly?
• Be maintained without removal from the pipeline?
• Can components be replaced without special tools?
• Is the valve simple to maintain?
• Does it offer long service intervals?
• Does the design allow for harsh conditions?
• Does the valve use trim materials to reduce erosion?
• Is it easy to adjust the valve to meet new demands?
• Does the valve offer smooth and accurate control?
• Does the vendor give high-quality technical support?
• Can the valve vendor deliver the valve quickly?

Once valves and actuators are installed, maintenance plays a critical role in keeping them up and running. The introduction of control systems using open communications standards has made this function easier. If smart positioners are incorporated into a network, web-based browsing technology can monitor the valves, collect performance trends, tabulate data, and post it to a web page where engineers can evaluate emerging problems and plan for cost-effective maintenance. Predictive maintenance provides trend data to identify which devices will need maintenance, what kind they will need and when.

This is article was written by: Patti Pool
Products Editor

The Advantages and Disadvantages of Ceramic Disc Taps

Taps drip. It's inevitable, like death and taxes.
Traditional taps seal using a rubber ring screwed down over
the end of a metal pipe. Sooner or later the rubber is
going to go hard, split or just wear away and it will no
longer seal. Then water seeps through, and the tap starts
dripping. Left alone the problem gets worse as the water
wears away the valve seat. Then you'll have to either
re-grind the valve seat(Do you own a valve seat re-grinder?
Who would?) or replace the tap. Tedious in either case.
But, it need not happen. Many taps now use ceramic discs.

Method of Operation

Instead of creating a seal by forcing a rubber washer onto
the end of the water feed pipe, they use two ceramic discs
each with matching slots in them. These are held over the
end of the water feed pipe. The lower disc doesn't move
while the upper disc is turned over the lower disc by the
tap head. Water will only flow when the upper and lower
slots match up.

Advantages

There are a number of benefits to this arrangement. The most
obvious is that ceramic discs are much harder than rubber
and much more resistant to erosion by water seepage. Hence
they have a much longer life before needing replacement.
Additionally, because the water flows between the two discs,
the discs erode not the metal of the valve. Also, because
of the way the discs are arranged, the taps go fully on with
only one quarter of a turn and tap needs only light pressure
to operate. This light action has the advantage that they
are easy to operate with the back of the hand if your hands
are dirty and for people with restricted movement.

Where they are Used

The ease of operation and the long life mean that most good
quality sink mixer taps have been made using ceramic discs
for a while, but basin taps with ceramic discs are
surprisingly less common. The more use a tap gets, the more
attractive the use of ceramic disc technology becomes. This
is doubly true in hard water areas, which can be murder on
traditional taps.

Disadvantages

Everything has it's downside, and there are cons to ceramic
disc taps. They do eventually wear out and are more
expensive than old style taps and are not suitable for very
low water pressure. Unusually, many of the manufacturers
seem to use standard sizes, so getting a replacement is
often straightforward. Because taps on basins can be either
handed or not not, one can't always be sure which way to
turn each tap on, this can be annoying! Lastly, unlike
traditional style taps, which take a number of turns to be
on full, you may easily turn the water flow on far more than
meant. The unexpectedly vigorous water flow and splashing
can cause water going everywhere, including over your
clothes. Not Good!

Bob Plum is the owner of BuyPlumbing co uk Ltd. If you live in Britain then the link http://www.buyplumbing.co.uk gives you access to a wide range of competitively priced bathroom goods and plumbing fittings.