ELECTROPLATING , ANODISING & GALVANIZING
The benefits of transparency in fluid handling
Fluid handling can be one of the stickiest points of a production process . Changes in viscosity , quality and pressure can all have a detrimental impact on the finished product , resulting in batches having to be destroyed and machine downtime as production lines are reset . Loris Medart , a fluid dispensing engineer with more than 20 years ’ experience and founder of feed systems manufacturer SR-Tek , outlines how introducing transparency into the process can prevent product faults , support planned interventions , and ensure consistent production .
Controlling the variable
Temperature , humidity , pressure and viscosity are just some of the variables that can affect the performance of fluids in a manufacturing process . As a result , it is often one of the most dreaded elements for many process engineers . With a small amount of effort , however , control and automation can be used to tame even the trickiest liquids . A key element of which involves treating this part of the production process as if it were a science experiment by fixing as many of the variables as possible .
The type of dispenser used and how it is set is often the main focus of engineers . This is important , but to truly control a fluid you need to consider the environment within the pressure tank . There are several added features and sensors that can be fitted to a vessel to fix the variables . Temperature control jackets for instance maintain the temperature inside the tank to keep material viscosity consistent throughout shifts and from batch to batch . This is particularly useful when it comes to handling and dispensing thread locks which are highly sensitive to temperature variation . A couple of degrees higher or lower is enough to affect viscosity and deposit sizes . Then there are thixotropic fluids , which see their viscosity drop as the result of movement . A good example of this would be wallpaper glue . At the start , the glue is often difficult to stir but the more you stir it , the easier it becomes to mix . What is happening here is that the viscosity of the material is changing as a result of the mixing movement applied to it . While this might not be so much of an issue for those doing home décor , in a production setting it can lead to dramatic inconsistencies resulting in too much or not enough material added to parts which may have to be reworked , cleaned or in some cases even scrapped . The answer lies in viscosity control which in this case might be through agitation . This can be either set as a fixed parameter for a full production day or coupled with sensors to adjust to changes within the fluid .
Real time monitoring and adjustment
Fluids , more so than many other substances in the production process , are heavily affected by the environment . A production plant operating in the Russian winter will need a whole different set of parameters to one operating in Spanish summer for the same application and fluid . The temperature changes do not have to be that extreme though , with a shift of just a few degrees from the morning to the afternoon at a UK site able to disrupt what had been a steady production process . In a traditional setting this will often lead to a lengthy reset as parameters are reviewed and adjusted to achieve optimum performance . Yet several major manufacturers have found a shortcut to this process , transparent tanks .
While most areas of production lines are visible to the naked eye fluids have remained hidden from view . Large industrial-sized steel tanks no more sophisticated than oversized paint pots have remained the norm . Yet production has moved on . Fluids have become more complex and expensive , shorter production runs and more diverse product lines mean huge simplistic containers are now a liability rather than an asset . For ABB , BMW and Johnson & Johnson the answer has been to switch to transparent tanks , where fluid levels , consistency and quality can be monitored not just by sensors but also by eye .
For a busy production line manager having to oversee all parts of the process , being able to see when a fluid needs topping up or adjusting from virtually anywhere on the line is invaluable . Added to this , common signs of issues within the fluid , which would previously lead to product faults , such as crystallisation , thickening of the fluid due to solvent evaporation , skinning or colour changes due to deterioration can be spotted early and resolved with less product wastage . It also enables engineers to spot faults further up the line such as air entering the tank and causing bubbles , or a faulty compressed air line leading to oil and detritus entering through the pressure pod .
R & D in production
In the main the scientific approach of testing , measuring and adjusting materials is largely confined to the R & D department . Yet , due to the many influences on fluids an ability to test and observe reactions in real-time is often invaluable . A great example of this was a project we recently completed for an automotive part manufacturer . The company had been using the same fluid provider for a number of years ’ there hadn ’ t been any changes to the composition or even transportation of the liquid , yet all of a sudden , they couldn ’ t achieve the necessary viscosity and production was brought to a halt . Having adjusted and tested all of the parameters and observed the reaction in real-time we identified a solution by controlling the viscosity through agitation . Agitation dropped this material ’ s viscosity to its set point allowing consistency from batch to batch , something that was not possible when the fluid remained static . What could have been weeks and months of lost production time as a new fluid was developed or sourced from an alternative supplier was solved through the simple application of agitation in the pressure vessel . With all other parameters confined the engineers are now able to eliminate batch to batch variation .
Fluid handling needn ’ t be rocket science . Controlling , monitoring and , where needed , adjusting parameters enables consistent production , reduces waste , and prevents unplanned downtime . Major producers like ABB are now bringing fluids into the light by using transparent pressure vessels to enable them to plan and adjust . Through this type of careful management there is no reason why even the most temperamental of fluids cannot be adapted to ensure consistent results .
Connect with Loris Medart on LinkedIn : www . linkedin . com / in / loris-medart-srtek /
Follow SR TEK on LinkedIn : www . linkedin . com / company / srtek /
40 JANUARY 2021 read online : www . surfaceworld . com