Monitoring on/off valve performance by Tyco

This report on a product launch presented recently by Tyco Flow Control describes a new Tyco on/off valve actuator, the AVID XamineR, with its intelligent monitoring systems

Plant engineers responsible for valve maintenance and performance on an existing process plant have heard all about intelligent valve actuators, and have probably seen demonstrations on digital systems.

Possibly they have some control valves on critical duties, or on new plant extensions, where such modern technology has been inserted, “to gain experience”.

These systems do not assist in the round of scheduled regular maintenance needed on the rest of the plant valves, typically on/off valves, hard-wired point to point and fitted with pneumatic positioners and switch boxes.

These valves give no data advising the earliest signs of trouble, there is no data coming back to warn of a potential failure.

How can they improve the efficiency of dealing with these valves, and reduce future maintenance costs, while using up or even extending the existing asset life? A solution to this might attract the interest of their plant manager.

Tyco Flow Control knows a lot about valves.

Tyco is the largest manufacturer of valves, actuators and associated products in the world, with over 90 well known brand names in their portfolio, like Anderson Greenwood, Keystone, Varec and Yarway.

Tyco have developed intelligent valve positioners for use on most of the different digital communication systems available today, like Profibus, Foundation fieldbus, AS-i bus and DeviceNet.

The development engineers within AVID Controls (another Tyco brand, where AVID stands for Automated Valve Interface Devices) decided that it was time to turn the problem round, and approach from the viewpoint of an existing installation.

How do you upgrade an existing population of pneumatic actuators and switch boxes, typically on on/off valves.

In the last five years Tyco have manufactured over 500,000 such actuators: so they know there is a large current population that will consider an upgrade: when plant efficiency improvements can be demonstrated.

AVID XamineR.

Enter the XamineR, an intelligent replacement for the pneumatic positioner and switch box used on any valve, whether on/off in function, or proportional.

The XamineR is retrofitted to existing valves within an hour, and drops into the wiring system in use, whether hard wired or on any standard open network: even the networks that cannot transmit diagnostics.

The XamineR uses a non-contact Hall effect valve position sensor, and integrates the pneumatic manifold block with solenoids in the unit.

With a new innovative spool, the unit will tolerate relatively dirty plant air lines: an essential feature based on years of plant experience.

Once in place, the commissioning and interrogation can indeed be achieved over a network connection: but if hard wired systems are used, the XamineR also has its own LCD display and function buttons.

The easier option however is intrinsically safe Bluetooth communication with a PDA: a tool becoming increasingly available on plant, and one which will pay many dividends when fitted with the relevant free Tyco AVID XtractoR software package.

But forget external monitoring, what does the XamineR do for you as an intelligent positioner? It monitors the air pressure profiles on supply, exhaust and differential pressure, and alarms if any of these exceed the adjustable set-points.

It allows independent adjustment of valve opening and closing speed control, and has alarm signals if the times taken deviate outside their set-points.

It monitors opening and closing positions, and allows alarms to be set if these are not achieved.

It records the valve opening and closing profiles against time, in the memory, for the original valve signature, and for the last four actions where an alarm was tripped, with a date and time stamp for those events.

It counts valve cycles and allows an alarm at a pre-set total, for maintenance alerting.

The easiest way to get these alarms is via the PDA: but the XtractoR display will signal them to a passing operator if there is no network to collect them.

Options include separated electronics and solenoid valves should the valve be subject to heavy vibration, or temperature, single or dual coil solenoids for ESD duties, and also a partial stroke test capability, at programmed times to a programmable extent, with results recorded and time stamped.

Plus there is a filing system: each unit records the valve serial number, installation and maintenance history, change record, on the positioner unit itself.

Software Diagnostics.

The AVID XtractoR software package is the software that enables the PDA or a PC attached to the digital communications network on the plant, if it exists, to access and download the XamineR memory, plot the open and close valve signature graphs, adjust the set-points and write to the valve management database stored in each valve.

Tyco report that the valve signatures seen using this positioner have enabled useful analysis of sticking and pneumatic supply performance, highlighting problems before they can affect plant performance.

Increased maintenance efficiency, reduced unplanned downtime, and extended valve plant life are seen as the initial benefits of the system, but the ultimate capability for remote checking of all plant valve performance will lead to further business services: like remote surveillance by Tyco experienced valve engineers to alert the busy on-site maintenance teams to the actual valves that need local attention.

Trial units of the AVID XtractoR are out on site now, with interested oil and gas, petrochemical and power industry users: the first units have been on display at recent Exhibitions in Rio de Janiero and Calgary.

Full product availability is scheduled for 1 January 2007, with approved units available suitable for Tyco and all VDI/VDE 3845 valves.