Sepro’s new patent application for elliptical hoses will have far-reaching benefits to not only the existing peristaltic pump world but may also be applicable to pinch valves and other pump types.
This innovation takes advantage of an “elliptical” shape in the new hose to improve hose life, pump at higher pressures, and allow for nearly double the maximum particle size as compared to conventional pumps.
Here is a quick summary of the benefits of our new elliptical hose:
- Longer Hose Life – Reduced fold angles ensures a very long hose life.
- Higher Pressures – A peristaltic pump equipped with an elliptical hose can pump at higher pressures compared to the circular-hose equivalent.
- Higher Pumped Temperatures – Elliptical hoses can pump higher temperature media at the same pressure compared to the circular-hose equivalent.
- Larger Particle Size Allowance –The elliptical C150 accommodates ~40mm particles, which is almost double the conventional pump allowance.
This technology stems from our R&D department addressing several issues in the mixing and pumping industry:
Opportunity For Stronger Hoses
Generally, there is a large opportunity for peristaltic pumps of high volumetric and pressure capacity, but circular hose designs cannot take advantage of this opportunity. Conventional peristaltic pumps with circular hoses cannot operate continuously at pressures above 16 bar (235 psi).
Here are a couple of limitations on conventional circular hoses:
- All peristaltic pumps have limitations on rotation frequency because of the heat generated during folding and unfolding of the hoses.
- Peristaltic pump hoses must be designed to resist vacuum collapse and should be able to withstand many cycles of folding and unfolding without delaminating.
Herein lies a conflict: thicker hose walls are necessary to resist vacuum collapse but may cause premature hose failure because of excessive heat generation.
Sepro’s novel solution to this conflict was to subtract wall thickness at the fold points while adding thickness to the wall portions that do not fold. This means that the interior surface of the hose is an ellipse, while the outer surface remains circular as in conventional designs.
Compared with Conventional Models
Making the fold points thinner while increasing the thickness of the rest of the hose presents a “best of both worlds” scenario. The elliptical hose has the same resistance to vacuum collapse as the circular hose yet requires ~50% of the sealing forces.
We have also addressed the limitation on rotation frequency with this new product. Elliptical hoses generate less heat than their circular equivalents, which means that a peristaltic pump equipped with an elliptical hose can pump at the same rate at higher pressure or a higher rate at the same pressure as the circular equivalent.
By addressing the limitations of rotation frequency and hose wall thickness, the elliptical hose provides a variety of benefits applicable to many industries.
Benefits and Applications
Ultimately, the simple benefit of the elliptical hose is increased hose life and higher pressures. However, this technology also opens the possibility for more powerful pumps due to its greater capacity for wear and tear.
The thinner side walls and lower fold angles in the elliptical hose allows for lower forces and stresses. The elliptical hose only needs to go through ~70° to seal, whereas a conventional circular hose must be folded through 90°.
Stress and force reductions will allow for the construction and successful operation of peristaltic pumps that are larger than those currently available on the market. In addition, hose life is expected to be longer in these larger pumps.
With elliptical hose technology, we are now able to design some of the largest pumps on the market. Sepro’s analysis has shown that it is feasible to construct a hose with the open area of a 200mm circular hose, which is almost double the capacity of the largest peristaltic pumps currently available on the market.
Which industries would benefit the most from these new elliptical hoses?
Thickeners are used in many industries including mining, and mining applications alone represent an extremely large market. Our new elliptical hose is perfect for an industrial, high capacity, high pressure, low profile peristaltic pump that would be suited to handling thickener underflows.
Since the elliptical hose can pass larger particles without risk of damage, this product is particularly relevant for any industrial installation that may occasionally experience tramp oversize.
We are beginning trials of the elliptical hose in existing Sepro pumps, so our customers can soon benefit from longer hose life and higher-pressure operations. Contact Sepro Mixing today to learn more about our elliptical hose!