Whether it be consumer goods or industrial products, many people now falsely associate new things to be ‘clean’. This widespread misconception of unused items being immaculate may not matter much in most situations, but there are instances where it makes a world of difference. Take, for example, kitchenware. When buying a new set of wine glasses or dinner plates, it is common knowledge to wash them first before putting them to use. After all, you never know where they have been before they reach your hands.
Why new hose assemblies need cleaning before use
This best practice is more so essential when working with hose assemblies and sourcing from a single OEM. Be it Teflon hoses or those made of steel or rubber, hydraulic hoses must be 100% clean to ensure they do not contaminate whatever medium they will be used for. Once these hoses finally arrive at your facility, they may appear spotless at first glance. Still, every step of their fabrication process generates internal contamination that is not readily perceptible to the eye. In short, from the manufacturer to distributor to the consumer, there are many ways for hydraulic hoses to get dirty:
- Residual mandrel lubricant is left uncleaned from the factory.
- Cutting modifications could leave rubber dust in the tube.
- Crimping hoses may cause small metal shards to break off into lines.
- Unsealed hoses will collect dust, dirt, and debris during transport and storage.
This step is more important than ever when buying hoses for modern hydraulic systems, given their increased sophistication compared to past designs, including tighter clearances and higher operating pressures.
Tips and benefits when cleaning hoses
Although it is highly inadvisable, many users often use a metal scallop blade or an abrasive wheel when cutting hoses, which tends to create internal contamination. A better option would be to use a production saw or a specialised tool designed specifically for cutting hoses, as they will produce less contamination and heat.
It is best to clean a hose immediately after cutting it down to size for a given assembly and before completing a hose stem insertion. Be aware that the cutting tool or blade will generate heat as it cuts through the hose, and the metal or rubber particles that get sheared off tend to cool and stick to the insides of the tube.
Therefore, cleaning hoses while they are still warm from being cut is highly recommended, as it is easier to remove contaminants before they get stuck. For instance, when using projectile cleaning, fire the projectiles through once the cut is complete.
Besides preventing user-induced irregularities in the hose tube, cleaning also simplifies the hose stem insertion process. Cleaning hoses somewhat generates a polishing or lubricating effect and eliminates any friction that pollutants may generate when pushing the hose stems in.
This also reduces the need to apply actual lubrication to the hose stem, which can be another source of contamination since many lubricants may not be fully clean – even out of a brand-new container – because they are not prefiltered. Lubricants also pose another issue: the uncertainty of their compatibility with the tube stock in the hose. Should a non-compatible lubricant be used, there is the risk of inadvertently softening the tube and shortening the life of the hose assembly.
Lastly, if there is still some contamination left at both ends when the hose stems get inserted, some of the particles will be pushed deeper into the hose, while others may get trapped between the inner diameter of the rubber tube and the outer diameter of the stem. After crimping, the trapped contaminants could cause fluids to leak when the system is under pressure, and this likelihood increases the greater the size and amount of the contaminants. However, using a clean tube and performing a proper hose stem insertion can eliminate this risk.
Whether it be fluids, gases, or other substances, it is essential for any medium that passes through hoses to come out the other end untainted. Given that there are plenty of opportunities for industrial hoses to get contaminated before making it to a hose assembly, following fundamental principles like initial cleaning can prevent issues during the actual operation and maximise the longevity and performance of the entire system they connect to.
If your project requires nothing less than high-quality industrial hoses, Pharmchem Engineering is the source you can trust for all your hose and hose fitting needs. Our extensive catalogue of industrial hoses includes stainless steel, silicon/Teflon, and rubber hoses, available in off-the-shelf configurations and custom options should your application require a tailored solution. For more information about our other industrial engineering supplies, such as breakaway couplings, pipe pigging equipment, expansion joints, and more, feel free to contact us anytime.