Each Cleveland Cascades system is made up of many individual parts and assemblies, all of which are vital to ensuring that the system is operating safely and achieving the expected results with respect to minimising dust emissions and material degradation and segregation.
Maintenance is essential to the longevity of any equipment or machine, hence why the aspects of the Cleveland Cascade system should feature in a planned preventative maintenance. There are components which will require more frequent inspection as they are more susceptible to ‘wear’ experienced during routine day to day loading operations.
This article aims to highlight some of the more critical components explaining their role in the system and the importance of maintaining their condition.
Cascade Cones & Wear Liners
The Cascade solution consists of an alternating series of inclined A & B cones which limits the flow velocity of the material to a more controlled speed.
The shape of the cone holds the dry bulk material in such a way that prevents particulate separation and minimises material degradation. The significantly reduced product velocity creates a “mass flow”, a stream of material moving as a single mass through the chute and onto a stockpile with minimised segregation. In doing so this technology practically eliminates dust generation at source without the need for expensive, energy intensive and high maintenance dust extraction and filtration systems.
As the cones are always present in the flow of material, it can be expected that wear will present itself due to the abrasive nature of the bulk materials being loaded. For this reason, a wear liner is installed to the running surface of the cone. If the liner was to be fully worn down then bulk product would come into contact with the cones and over time cause damage.
It’s imperative that the wear liners are inspected regularly to assess their condition. If excessive wear is noticed then the liner should be replaced at the earliest opportunity to protect the cone body. If the cone was to become damaged then it should also be replaced as this could affect the systems performance.
The strops act as the main support for the Cascade Cones and provide the correct spacing and loading angle as defined during the design and commissioning phases of a project.
Being a load bearing and wearing part of the system, it is important that they are inspected and replaced at regular intervals. This is the best method for ensuring that the strops in service retain their high safety factor, any fraying/damage can significantly reduce their strength so if identified immediate replacement is necessary in order to prevent strop failure occurring.
The guidance provided by Cleveland Cascades is as follows; for high duty systems, the strops should be replaced every 12-18 months, for low duty systems, replacement should occur every 18-24 months. In both instances, if 2,000,000 tonnes of material is loaded prior to the time period elapsing for each duty type, the strops should be replaced.
If a set of strops were to fail during loading then this could lead to other equipment becoming damaged as well as causing excessive downtime.
The shroud assembly consists of a telescopic cover located over the Cascade cones which prevents side-winds from generating dust emissions. Dust which is generated during loading is encapsulated within the shroud preventing fugitive dust from escaping into the surrounding atmosphere.
Due to the constant extending and retracting of the system, the shroud sections can become worn over time. Another factor which can cause wear is material build up. At the end of each loading cycle the system should be fully extended to clear any trapped material that may remain within the lower folded shroud sections.
With regard to the shroud, wear can present itself in the form of a small tear/rip or if left could propagate causing a larger tear/hole. Minor wear and tear can be patched and repaired but excessive wear will require the replacement of the full shroud section.
The condition of the shroud should be visually monitored and checked periodically by operatives to retain optimal dust control levels.
The skirt assembly consists of an attachment ring to which are bolted several rubber leaves with a canvas over cover. The skirt attaches to a flange at the bottom of the carrier outlet and is designed to aid maximum dust control at the point of material delivery from the Cascade.
The segmented skirt opens as the pile of material builds below the carrier forming a seal, this seal should be maintained during loading allowing the MDS system to automatically raise the chute rather than manually controlling it.
Checks should be performed on the inner rubber leaves for wear, the rubber leaves should hang free from the skirt ring. Leaves that are excessively worn or damaged should be replaced, the same applies to the skirt canvas if the edges become ripped or frayed. If left in this condition, it will negate the effect of the skirt assembly as the seal will be compromised.
The above assemblies are just a few examples of the more common wearing parts of the Cascade System. If you would be interested in a health check inspection of your existing system then please contact us, our skilled site service engineers are capable of identifying any issues during the chutes operation and can advise on any spares replacements that may be required to optimise performance and reduce unnecessary downtime. We also offer dust analysis testing which can be carried out alongside an inspection.
During 2023 we have worked with a number customers that have had unfortunate breakdown scenarios due to external unforeseen factors such as adverse weather and accidental damage, with a suite of spares held on site, the downtime can be reduced to a minimum whist replacements are installed from stock.