Valves, Actuators & Pump Control


Protect your pump and keep it longer

July 2021 Valves, Actuators & Pump Control

In today’s complex and frequently rugged process plant environments, liquid pumps are often over-worked and under-protected from adverse operating conditions. Many pumps run nearly non-stop 24-hours a day over multiple shifts. Poor operating conditions can reduce pump performance, require extra maintenance, shorten their lives and increase costs.

Unexpectedly losing a pump is often an expensive or even a dangerous problem in a chemical plant. The results of a pump failure potentially range from the loss of product in sensitive pharmaceutical batch control applications to damage to other nearby equipment from pressure build-up of material that isn’t moving, or even to safety hazards when a pump fails to shut down and literally burns up in the presence of combustible materials. It really pays to protect and care properly for pumps.

Adverse pump operating conditions

Two of the more common problems that can negatively affect pumps are wet/dry conditions and flow disturbances – both of which are preventable.

Nothing damages a liquid pump faster than the heat built up from dry running conditions, which occurs when liquid stops flowing into the line or the pump. When the liquid isn’t there to provide cooling, the heat can destroy a pump’s bearings. If repair is even possible, it is going to be an expensive proposition. For proper and efficient operation, pumps require a stable upstream flow profile in the pipeline before liquid enters the pump. When elbows, valves or other equipment are installed too close to a pump, these other devices can create swirl and velocity profile distortion in the pipeline. These disturbances can result in excess noise and cavitation, resulting in reduced bearing life.

Wet/dry conditions

Installing a point flow/level switch in a pump’s process loop eliminates the damage caused by a pump running dry. Point flow/level switches are capable of detecting not only a low flow situation, but also detecting a dry running condition. This capability allows the control system or operator to take corrective measures before the bearings of the pumps are overheated and fail. Among the many types of point flow/level switches available is FCI’s FlexSwitch FLT Series, which offers dual alarm capability.

Alarm 1 will detect a low-flow situation, which can be regarded as a pre-warning signal for the control system or operator. The system or operator can then decide to keep the pump running or to shut it down.

Alarm 2 occurs if the feed line to the pump is running dry, which would be an emergency signal to shut down the pump because the bearings now see gas instead of a liquid as a heat transfer medium. In this case, the temperature of the bearings may rise very fast. The flow switch prevents permanent damage to the pump’s bearings.

This flow switch is a dual-function instrument that indicates both flow and temperature, or level and temperature sensing in a single device. Available in either insertion or in-line styles for both pipe and tube installation, a single switch measures and monitors flow or level and temperature simultaneously with excellent accuracy and reliability. Dual 6 A relay outputs are standard and are assignable to flow, level or temperature.

The switch operates over a wide flow range, making it suitable for liquid pump protection. Switch point accuracy of 2% and measurement repeatability of 0,5% of reading ensures accurate, reliable operation. The standard configuration withstands operating temperatures up to 175°C, with optional versions available up to 455°C.

Conclusion

If liquid pumps are an important part of a process, then make the investment to protect them from dry running conditions and flow disturbances. You’ll not only ensure that your pump lasts longer, but you just might improve the efficiency of the process, reduce unnecessary maintenance costs and prevent accidents.


Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Ball valves and actuators optimise HVAC performance
Schneider Electric South Africa Valves, Actuators & Pump Control
Schneider Electric offers the full range of innovative SpaceLogic and EasyLogic ball valves and actuators. These cutting-edge products are designed to optimise HVAC system performance, ensuring comfort and energy efficiency in commercial and residential buildings.

Read more...
Alfa Laval expands hygienic valve portfolio
Valves, Actuators & Pump Control
Alfa Laval is expanding its hygienic valve portfolio by introducing the Unique SSV pressure relief valve and the Leakage Detection butterfly valve, alongside new smaller sizes of the Unique Mixproof CIP and Unique Mixproof process valves.

Read more...
Preparing pump systems for adverse weather conditions
Valves, Actuators & Pump Control
As the severity of storms in South Africa increases, so has the rush of sediment-laden water become a major issue and a significant challenge for irrigation. When sediment levels rise to just 10 grams per litre or more, the risk of pump wear and dam silting increases dramatically.

Read more...
High-flow solenoid valve
Emerson Automation Solutions Valves, Actuators & Pump Control
Emerson has introduced the new ASCO Series 327C solenoid valve, which features a direct-acting, high-flow design that provides superior flow-to-power ratio. It permits high flows at minimum power levels, making it ideal for use in power plants, refineries, and chemical processing facilities.

Read more...
Proportional cartridge valve series is the fastest in its class
Valves, Actuators & Pump Control
Parker Hannifin is introducing the enhanced version of the proportional cartridge throttle valve series, TFP. The new pilot valve further reduces the step response times by up to 30%, making the TFP the fastest valve in its class.

Read more...
Proportional cartridge valve series is the fastest in its class
Valves, Actuators & Pump Control
Parker Hannifin is introducing the enhanced version of the proportional cartridge throttle valve series, TFP. The new pilot valve further reduces the step response times by up to 30%, making the TFP the fastest valve in its class.

Read more...
Inspection system for leak detection in valves in hazardous areas
Extech Safety Systems Valves, Actuators & Pump Control
Leaking valves in industrial plants not only lead to loss, safety risks and possible contamination and pollution, but also result in high economic costs. Therefore, valves in hazardous areas require regular proper inspection and preventive maintenance to ensure their functionality.

Read more...
Control head for automation of hygienic process valves
Burkert South Africa Valves, Actuators & Pump Control
Burkert’s Type 8681 control head is optimised for decentralised automation of hygienic process valves. Thanks to its universal adapter, it can be combined with all normal commercial butterfly valves, ball valves and single- and double-seated valves.

Read more...
Hydroformed tube valve body
Burkert South Africa Valves, Actuators & Pump Control
One of the most common necessities for manufacturing pharmaceuticals, cosmetics, food and beverages are diaphragm valves. What used to be a dull two-way race between forged and cast body variants is now being challenged by an exciting, ground-breaking technology. The hydroformed, light-weight diaphragm tube valve body will change the way you think about plant design and operation.

Read more...
Global pumping giant ready to support hydrogen economy
Valves, Actuators & Pump Control
With abundant sunshine and wind, southern Africa is perfectly positioned to become a global powerhouse in green hydrogen production. Two key projects are already in advanced stages of development in Namibia. KSB has identified the vast potential of these types of projects in southern Africa, and through its KSB Pumps and Valves subsidiaries in Namibia and South Africa is investing heavily in bringing the right skills to the region.

Read more...









While every effort has been made to ensure the accuracy of the information contained herein, the publisher and its agents cannot be held responsible for any errors contained, or any loss incurred as a result. Articles published do not necessarily reflect the views of the publishers. The editor reserves the right to alter or cut copy. Articles submitted are deemed to have been cleared for publication. Advertisements and company contact details are published as provided by the advertiser. Technews Publishing (Pty) Ltd cannot be held responsible for the accuracy or veracity of supplied material.




© Technews Publishing (Pty) Ltd | All Rights Reserved