Good tyres are vital in quarrying and mining, and manufacturers are constantly improving and introducing new specifications. Patrick Smith reports.
The importance of good tyres in general can never be overstated, and in quarrying and mining, the cushions between machine and surface are vital.
While they are big and expensive, they offer safety, and as a major ongoing cost for operators, the longer they last the better for production.
Manufacturers are constantly improving and introducing new tyres for wheeled loaders, rigid and articulated dump trucks, and other associated equipment.
For example, in Italy the family-owned Dal Zotto company, now managed by third generation family members, has fitted
The tyres, chosen with the help and support of its tyre dealer Moretto Pneumatici, are four Earthmax SR 30, size 26.5 R 25, which are specifically engineered for articulated dumpers and wheeled loaders.
Dal Zotto, based in Crocetta del Montello Treviso Province, north of Venice, specialises in inert materials processing and supply, excavation, demolition, recovery, and recycling. Target customers are dealers and stores, construction companies and building constructors as well as floor layers and tilers.
The company, founded in 1958, can provide small and large material quantities for any need in the construction business, and it has developed a range of pre-packaged and pre-dosed inert materials in 25kg sacks that are ideal for smaller operations in the field of construction or green building and are suitable for both new constructions and restoration of existing buildings.
The company’s range of CE-marked natural inert materials includes several types of sand, rubble, gravel, crushed materials, and mixed bulk goods. The offer also comprises CE-marked recycled aggregates.
The company also provides excavation services for the foundations of residential and industrial buildings, river-bed recalibration, hydraulic maintenance work of waterways, environmental restoration, and raw material quarrying. In addition, it deals with the entire process of recovery and recycling within demolition works.
The L150F wheeled loader is used for loading the inert materials and feeding the processing plants in a gravel yard.
“We purchased our first BKT Earthmax SR 30 tyres in 2014. At the end of every product life-cycle, we bought them again without any hesitation. We won’t step backwards, since we have found our ideal tyre,” says Franco Dal Zotto.
“We purchased the tyres through our local dealer Moretto Pneumatici, headquartered in Montebelluna in the province of Treviso, who assisted us in choosing the ideal tyre for the type of equipment, application and use.
“He actually suggested us to test Earthmax SR 30 from BKT for our main loader.”
Moretto Pneumatici is serviced and supported by Univergomma, the national tyre dealer for BKT-branded tyres in Italy.
Franco Dal Zotto says the tests carried out in 2014 with the BKT tyres were convincing, and his company decided to fit the BKT tyres XL Grip and Rock Grip in size 16.00–25 to its Perlini DP 255 dumper, which were tested during gravel extraction works at the Piave River.
“The BKT tyres stood up to all promises and went beyond expectations. We are fully satisfied from any point of view: operation, quality, durability, and operating hours.
“Earthmax SR 30 is the perfect tyre for this kind of application, since it has been designed for the toughest operations. It is very resistant and shows stability in addition to excellent traction
“Thanks to the BKT products, we have noticed a general reduction of the overall costs as well as better driving comfort for our operators,” says Franco Dal Zotto.
The company’s fleet also includes a second Volvo L150F loader for its recycling plant and a Caterpillar 966 loader for secondary works at the plant. In addition, it has four crawler-mounted excavators and eight trucks.
BKT says its Earthmax SR 30 has a special tread compound, developed by the company, that enables the tyre to withstand cuts and abrasions as well as to dissipate the heat created during the loader’s operations.
Earthmax SR 30 is available in six different sizes: 15.5 R 25, 17.5 R 25, 20.5 R 25, 23.5 R 25, 26.5 R 25 and 29.5 R 25.
Meanwhile,
“Load capacity is key to all earthmoving machinery and the new reinforced casing of the new Michelin Xtra Load makes it the first 24.00R35 tyre on the market to be credited with a three-star rating,” says Michelin. (Previously most 24.00R35 tyres carried a two rating; the Xtra Load is the first carrying a three rating. Star rating is the industry indicator of load capacity for a given dimension, Tyre and Rim Association).
“This is the result of an optimised design which improves stress distribution within the tyre. In practical terms this equates to an 8% higher payload or an increase of 9 tonnes in load capacity per machine; a huge increase in productivity when multiplied by the number of cycles made daily.
“With an increase of 9tonnes in load capacity per machine, this is a huge increase in productivity when multiplied by the number of cycles made daily.”
Both tyres are also said to offer improved life and increased productivity due to an improved tonnes/kilometre/hour (TKPH), and the Xtra Load range is said to benefit from improved wear life thanks to an improved wear resistance of + 8% compared to its predecessor.
“With the two tread compounds (A4 and B) this means a simplified range for users and easier stock management for dealers,” says Michelin.
“Productivity, as measured by TKPH, quantifies productivity and is a function of load and distance covered in an hour. For, respectively, the new Xtra Load Grip and Xtra Load Protect, the TKPH is increased by at least 20.3% and 13.8% in the A4 compound, and at least 11.7% and 41.7% for the B compound, when compared against previous Michelin ranges. Heavier loads can be moved further, over the same time,” says Michelin.
The new Michelin Xtra Load tyre is available in two variants, targeted at the two main surfaces experienced by RDTs.
Michelin Xtra Load Grip, which replaces the XDT and Xtraction tyres, is for soft, loose, muddy ground conditions, while the Michelin Xtra Load Protect, which replaces the XQuarry and XHaul tyres, is for hard, sharp abrasive conditions on flat, dry surfaces.
The company has also unveiled the Xtra Defend tyre, designed for ADTs with payloads between 25-45tonnes. It is available in two dimensions, 23.5 R 25 and 29.5 R 25, and is said to be characterised by an outstanding TKPH performance; a longer lifespan of 15%; increased density of steel in the crown area, and 15% thicker side walls.
“The updated W2 compound improves on what was an already high performance of the original compound,” says Luca Mai, Marangoni’s sales director EMEA for OTR tyres. “It offers 10% better tread wear, lower penetration of stones and rocks, and lower tear propagation.
“As a company, we are all about giving a good additional life to a tyre. It’s in our DNA. However, our retread tyres offer not only more longevity. For example, we estimate that retreading a 45/65R45 tyre for wheeled loaders saves more than 50% of the oil required to manufacture an equivalent sized new tyre. Retread tyres also use a lot less raw materials than new tyres. All this makes retread tyres a very environmentally friendly and financially shrewd alternative.”
Mai was speaking during steinexpo 2017 where Marangoni was represented by its German distributor, Recamax.
“Germany is a very important market for us. We are selling our high quality retread tyres all over Europe,” says Mai.
Marangoni says its OTR retreading process preserves about 80% of the old tyre and saves up to 70% of the energy associated with making a new one. Each year this amounts to saving thousands of tonnes of raw materials such as rubber and steel, significantly contributing to global CO2 emission reduction.
The company estimates that four 23.5R25 retreaded tyres generate 2.5tonnes less CO2 emissions than their new equivalents (one year of emissions for an 80m² apartment).
The company says it now offers a broad product range with over 40 profiles in a total of around 180 sizes for various applications.
Bridgestone says that the VLT tyre offers excellent manoeuvrability, traction and off-road capability, and thanks to its excellent stability it also provides a very good driving feel.
The VLT is currently available in the dimensions 20.5 R25 to 29.5 R25, 33.25 R29 and 750/65 R25.
At the recent steinexpo 2017, Bridgestone also displayed its V-Steel Rock Quarry Premium (VRQP), a radial tyre that has been developed for tipper trucks in a heavy stone crusher operation.
In France,
The company says that after 3,600 hours use, 66% of the Magna MA08 tyre’s tread depth remained, which leads to a tyre life of over 9,000 hours.
“The Magna MA08 is designed for use on wheeled loaders, dozers and graders requiring maximum traction. The optimised square-shouldered design provides stability and protection from cuts.”
Magna says that the L5 open tread pattern on the all-steel radial construction tyre provides grip and traction, while improved protector plies optimise load performance and operator comfort, and new, improved technology of the high-tech casing reduces heat build-up inside the tyre.
When looking at application requirements for wheeled loaders, Camso believes that traction, durability and stability are key factors in keeping loads moving to minimise cost per operating hour.
In the last year, Camso has introduced two new bias-ply tyre solutions for wheeled loaders.
It says the Camso WHL 775 is a tough and durable L5 bias wheeled loader tyre built with durability in mind to overcome heavy-duty hard surface applications, while the Camso WHL 773 has been designed for abrasive, rocky and harsh surfaces.
“These two tyres are part of a larger range of different bias and radial tyre solutions, among which we find the Camso WHL 775R and WHL 753R radial tyres especially suited for extreme hard surface applications and for general-duty mixed surface applications respectively,” says the company.
“With an extra-deep L5 lug tread combined with a heavy-duty sidewall, the Camso WHL 775R has maximum longevity and increased puncture resistance. With excellent stability and resistance to cracking it is the ideal radial tyre solution for extreme mixed- and hard-surface wheeled loader applications.
“The optimised non-directional stepped tread design of the Camso WHL 753R E3/L3 provides excellent traction and durability while ensuring debris cleanout. Its tapered tread lugs result in excellent operator comfort by minimising vibrations.”
