Mobile crushing and screening solution in China
In order to continue to grow and supply aggregates and materials, the company identified a need for a modern, versatile and highly productive crushing and screening solution. To this end, Hunan Yan Run chose a Sandvik QI442 HS and QA335 Doublescreen.
Satisfying requirements
Due to its varied customer base and their exacting and diverse requirements, Yan Run became aware of the need to update its equipment fleet, specifically its mobile crushers and screeners. The outmoded existing fleet could no longer provide the accuracy or versatility the company requires, nor deliver the bottom line performance or meet China’s increasingly stringent environmental legislation. All in all, a modern solution was required.
Although involved in a variety of related construction activities, the core business activity for Yan Run is aggregates, whether for its own use or supply. When a site is excavated, a great amount of the material can be processed to be used on site as foundations or sold to other construction companies. In addition, the company also processes quarried limestone, producing aggregates mainly for concrete batching plants as well as purchase by other companies. To this end, Yan Run had quite exacting requirements for any new crushing and screening plant. It would have to accept a feed size of around 500 mm and produce highly accurate fractions (0 – 5 mm, 5 – 10 mm, 10 – 20 mm, 20 – 31.5 mm) at a constant production rate of 200 – 250 t/h. In order to source this combination, Yan Run turned to POTA Environmental Technology Co., Ltd.
The company supplies a full range of modern mobile crushing and screening solutions, being Sandvik Mobile Crushers and Screens authorized distributor. Having gained an understanding of what Yan Run required, POTA recommended Sandvik Mobiles’ QI442 HS, its latest tracked impact crusher with modular hanging screen unit, one of its latest developments, as well as a QA335 Doublescreen. This provided Yan Run with a mobile crushing and screening solution with the highest environmental credentials, as well as possessing features which would enable highly productive and profitable use. Furthermore, the combination of impact crusher with triple deck hanging screen on the QI442 HS was seen as the ideal combination for Yan Run’s diverse requirements.
Crushing and screening in one unit
The Sandvik QI442 HS impactor (and QA335 which is part of Sandvik’s unique Doublescreen range of tracked screeners) supplied to Yan Run came equipped with a range of customer focused features. These are designed to improve return on investment and usability for the operator. A pre-screen is fitted to ensure maximum scalping capability and to prevent any undersize material passing through the impactor, thus maximizing throughput and reducing wear costs. This also allows a specific sized product to be produced from the natural fines conveyor. The pre-screen also has a choice of grizzly or punch plate top deck and mesh bottom, providing the flexibility to suit any application with the underpan feeder drastically reducing spillage generally associated with impact crushers.
The crusher’s CI621 Prisec Impactor, which comes with a host of innovations for improved efficiency and greater safety during maintenance, provides the ability to operate in either primary or secondary crushing modes. Additionally, the two hydraulically assisted curtains can be readily adjusted to produce a wide range of high quality product sizes.
Another major benefit incorporated into the QI442 HS model is the modular hanging screen system. This is interchangeable and offers the flexibility for the crusher to operate in open or closed circuit. The design enables set-up in less than 30 minutes and can be fitted without the use of additional lifting equipment. The patent pending hanging screen option delivers multi-functionality as a 1, 2 or 3-way split screener, as well as operation as a highly productive and efficient impact crusher. The double deck hanging screen enables the machine to produce two screened products and recirculate the oversize back into the feed conveyor. The oversize conveyor may be hydraulically rotated for material stockpiling (90 °) of up to three products on the floor, or removal (180 °). The tail section can be raised hydraulically to give improved ground clearance for transport when loading or unloading. Combined with the Doublescreen action of the QA335, Yan Run now has the capability to produce highly accurate gradings and fractions in one swift and effective process.
As with all Sandvik’s tracked range of crushing and screening equipment, both models are fitted with Sandvik My Fleet remote monitoring system as standard. Through the collection and accurate monitoring of a wide array of parameters, this facilitates customers accurate production forecasting, ensuring that the most efficient use is obtained from equipment, and thereby maximizing return on investment.
Since commissioning, the Sandvik crushing and screening combination has consistently worked at 250 t/h, producing the required fractions, very accurately. The Sandvik Mobiles QI442 HS and QA335 Doublescreen have proven to be easily maintained and serviced thereby ensuring that any machine downtime is limited whilst also proving to be versatile to deal with any unexpected requirement.
