The complete guide to fluid management
Fluids are often seen as one of the trickiest and stickiest points of the production process, placing a limitation on what can be achieved through continuous improvement and in the worst cases causing product failures that are both costly and time consuming.
The 4 steps to consistent fluid performance
Step 1 External Environment
There are some practical steps that can be taken to reduce the impact of the external environment. Minimising feed lines by ensuring fluid is stored as close to the dispenser as possible is one option, as this will drastically reduce the time that the fluid is outside of a controlled environment (see Step 2 – Internal Climate).
The oversized nature of traditional vessels, typically built for large quantities of cheaply available, low-quality fluids, meant it was almost impossible for machine builders and production line engineers to locate fluids close to the dispensing point in the past. However, with a thorough understanding of the fluid and application it is now possible to specify a compact pressure vessel that can be incorporated as and where needed. Where minimising the distance between vessel and application isn’t possible, insulated feed lines can be added to help mitigate environmental changes.
Step 2 Internal Environment
A lack of internal temperature control during production can lead to inconsistent performance, parts failure, machine downtime and, in the worst cases, costly chemical alterations to create bespoke fluids.
While a lot of focus is given to dispensing, industrial fluids can spend as much as 90% of production time in the reservoir.
A key way to mitigate the impacts of moving fluid from storage line and any changes during process itself is to ensure full temperature control during production.
Full temperature control at this stage not only ensures consistency at the point of use but can also enable operatives and line builders to optimise fluid performance, reduce waste and eliminate fluid related parts failure.
Step 3 The Top to Bottom Effect
Essentially, it gives an indication of why a fluid’s performance may change dependant on the amount that remains in the container when all other parameters are set. In manufacturing terms, operatives have long noticed a steadily decreasing flow rate when using a time / pressure system.
The pressure remains consistent, the volume of fluid has decreased, and the compressed air has increased. The top to bottom effect is caused by the constant change in volume of air and fluid inside the vessel. As the fluid level goes down inside the vessel, the volume of air increases but the ratio of compressed air, at a given pressure is not linear in comparison to that of the fluid.
The solution can be pieced together by a combination of using the right sized vessel and managing the pressure in a more precise way, enabling control over the amount of compressed air inside the tank, to deliver a consistent amount of force.
Step 4 Agitation
Thixotropic fluids such as UV adhesives, Epoxies, Silicone, RTV (room temperature vulcanising), rubber sealants and heat sink compounds are viscosity changing material between static and motion state.
Controlling the viscosity of such fluid lies control 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 itself.
While the dispensing head is an important focus point, it’s also important to monitor and set the air pressure regulation that will be applied into the tank. With all other parameters set, pressure can be used as the variable and can be controlled over time to ensure flow rate remains consistent throughout the production cycle.
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.
Conclusion – Taking control of fluid performance
Major manufacturers in many industries such as automotive, electrotonic, aerospace, medical, pharmaceutical are simplifying fluid handling by using increased automation and transparency 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 tamed to ensure consistent results.
The golden rule when it comes to fluids, whether you’re speaking to fluid manufacturers, machine builders, pressure tank manufacturers or dispensing companies, is that excess information is far preferable to too little. Working with a respected specialist within each field will ensure the best possible result at a fraction of the time and cost.
Kanban and continuous development are now central to manufacturing, whether driven by research and development, internal quality assurance teams, OEMs and client companies, or ever-changing legislation. As the familiar adage goes however, ‘insanity is doing the same thing over and over again but expecting different results.’