I. Development Prospects

　　With the rapid development of national infrastructure, the demand for construction sand continues to grow. Faced with a shortage of natural sand resources, many regions in China have witnessed unregulated extraction and illegal mining. In recent years, practices such as reclaiming farmland for sand mining and excavating sand from riverbeds have become widespread, damaging valuable arable land and flood-control embankments while also leading to numerous engineering accidents. As a result, natural sand—a vital resource—has seen its reserves dwindle, its quality deteriorate, and its price soar. Consequently, identifying alternative sand sources has become an urgent priority. Actively leveraging solid waste materials like tailings and construction debris to replace natural resources and developing manufactured sand and gravel has emerged as one of the key strategies for addressing the growing shortage of construction sand. The state adopts a supportive stance toward the development of manufactured sand, and it is widely believed that, amid the gradual depletion of natural sand reserves, manufactured sand will enjoy even brighter prospects.

　　II. Raw Materials and Processes

　　The raw materials used for producing manufactured sand are not particularly demanding; medium-hard rocks such as pebbles, basalt, granite, and bluestone can all be employed. In terms of sand-making processes, two well-established methods are currently in use: wet‑process sand making and dry‑process sand making.

　　The wet sand-making process consists of the following steps: feeding, crushing, sand production, sand washing, and wastewater treatment.

　　The dry-process sand-making process is as follows: feeding — crushing — sand production — screening.

　　First, the most obvious distinction between dry and wet sand‑making processes lies in whether water is required—this is why wet‑process sand production predominates in the water‑rich southern regions. The dry process does not rely on water, thus avoiding environmental constraints, but it typically demands higher‑quality raw materials, with strict limits on impurities such as clay content. While conserving water and reducing water pollution, the dry process generates substantial dust, leading to dust‑related environmental concerns that necessitate additional control measures. Each method has its own advantages and disadvantages; when making a choice, it is essential not only to consider local conditions but also to carefully evaluate costs and specific project requirements to ensure informed decision‑making.

　　● Sand-making equipment

　　Currently, the sand-making machines widely marketed on the market include hammer crushers, jaw crushers, roller‑type sand makers, vertical shaft impact crushers, mobile sand-making plants, hydraulic open‑cavity sand makers, impact crushers, and rod mills, among others.

　　● Hammer crusher:

　　The operating principle involves a rotor equipped with hammerheads that, through high-speed rotation, subjects the feed material to impact, crushing, shearing, and grinding, thereby achieving size reduction. The entire sand-making process is smooth, straightforward, and free from blockages, delivering outstanding performance. It is widely used in sand production, mineral processing, cement, metallurgy, chemical engineering, and building materials industries, offering distinct advantages in product particle shape. As such, it is a commonly employed piece of mining equipment for crushing and shaping stone materials.

　　Advantages: 1. Compact and well‑designed structure ensures reliable production capacity; 2. Unique dust‑proof sealing system extends service life and provides timely alarms in emergencies; 3. Distinctive crushing chamber geometry yields superior product particle shape and high gradation, minimizing needle‑like and flaky particles while delivering stable discharge; 4. Equipped with hydraulic locking and hydraulic adjustment for effortless operation, along with iron‑release and cavity‑clearing functions for enhanced safety.

　　Drawbacks: The hammer‑type sand maker’s shaping performance is “slightly inferior,” but it can meet the processing needs of a wide range of customers, offering improved cost‑effectiveness. If the raw material is relatively large and requires one‑step shaping—transforming bulky stones into fine sand—the machine’s processing capacity becomes more limited. Depending on the characteristics of the feed material and the desired product, the hammer‑type sand maker’s throughput ranges from 50 t/h to 900 t/h.

　　● Jaw crusher

　　It is primarily used as a primary and secondary crusher for medium‑size crushing of various ores and large‑size materials, and is widely employed in industries such as mining, metallurgy, building materials, highway construction, railway engineering, water conservancy, and chemical processing. The maximum compressive strength of the feed material is 320 MPa. Its key features include a high reduction ratio, uniform product particle size, a simple structure, reliable performance, easy maintenance, and low operating costs; it is also less prone to blockages when handling highly moist, sticky ores. However, it has certain drawbacks: relatively low throughput, high energy consumption, significant vibration, a limited reduction ratio, uneven product particle size, and an inability to fully accommodate the feed rate. When selecting primary crushing equipment, a comprehensive analysis and comparison should be conducted based on specific site conditions. Large‑scale mineral processing plants typically opt for gyratory crushers, while medium‑ and small‑sized plants—particularly those handling sticky materials—are better suited to jaw crushers. In general, the selection of a crusher should be preceded by detailed calculations and a techno‑economic evaluation to ensure an informed decision.

　　● Roller sand-making machine

　　Also known as a double‑roll crusher, it is used for medium‑ and fine‑crushing of ores and rocks with a hardness below medium, making it particularly well suited for crushing raw coal (including coal gangue) in large coal mines or coal preparation plants. The machine relies on a drive system consisting of two electric motors that transmit power via V‑belts to pulleys, which in turn drive the two rolls to rotate in opposite directions, thereby crushing the material by compression. Advantages: low energy consumption and excellent sand particle quality; disadvantages: relatively low throughput and a lower yield of finished product.

　　● Vertical Shaft Impact Crusher

　　The vertical shaft impact crusher, commonly referred to as an impact crusher or sand-making machine, is a high‑energy, low‑consumption crushing device that meets international advanced standards. Its performance plays an irreplaceable role among various fine‑crushing equipment for ores, making it the most effective, practical, and reliable stone‑crushing machine available today.

　　Vertical shaft impact crushers are widely used in the production of artificial sand from metallic and non-metallic ores, cement, refractory materials, abrasives, glass raw materials, construction aggregates, river pebbles, and natural stones (such as limestone, granite, basalt, diabase, and andesite), as well as from ore tailings and stone chips. They are also employed for manufacturing construction aggregates, highway pavement materials, subbase materials, and aggregates for asphalt and concrete. Additionally, these crushers excel in the fine crushing and coarse grinding of various metallurgical slags, particularly demonstrating superior performance when processing medium‑hard, extremely hard, and abrasive materials such as silicon carbide, carborundum, sintered aluminosilicate, and magnesia, outperforming other types of crushers in these applications. When paired with a hydraulic‑protected jaw crusher, they can handle a wide range of metallurgical slags. They are especially well suited for producing sand for construction and road‑building applications.

　　In terms of its operating principle, impact‑type sand making essentially relies on the “stone‑on‑stone” mechanism. As the rock particles fall naturally, they collide with other particles accelerated and thrown out by the impeller, thereby achieving crushing. During operation, wear on the machine’s impact plates is minimal.

　　Product features of the vertical impact crusher:

　　● Excellent product particle shape

　　It improves sand-making and shaping performance by 30% compared to other conventional equipment.

　　● Automatic detection, safe and reliable

　　Install vibration monitoring and alarm devices to protect the machine.

　　● Large processing capacity and high throughput

　　Compared with conventional equipment of the same power, output has increased by 30%.

　　● Easy to install and simple to operate

　　Lightweight, with versatile installation options, and capable of mobile mounting.

　　● Thin-oil lubrication, automatic maintenance

　　Genuine German thin-oil lubrication stations extend maintenance intervals and service life.

　　● Hydraulic Open-Box Sand Maker

　　The hydraulic‑open‑box sand maker is an improved version of the “river pebble sand maker.” Traditional sand-making machines, lacking a hydraulic assistance system, require time‑consuming and labor‑intensive disassembly and maintenance, thereby disrupting production. By contrast, the hydraulic‑open‑box sand maker employs an impact‑on‑impact crushing principle, offering selective crushing and producing products with relatively uniform particle sizes and predominantly cubic shapes, making it well suited for large‑scale operations with capacities ranging from 50 to 300 tons per hour. It finds extensive applications in bridge construction, high‑speed road building, port development, and airport construction.

　　● Mobile Sand Making Machine

　　Mobile sand-making machines are a product of modern demand, characterized by their mobility and ability to meet diverse crushing needs—ranging from coarse to medium, fine, and ultra-fine crushing, as well as screening—within complex construction waste. These machines can be positioned directly on-site, transported to the job location without additional handling, and produce finished aggregates on‑site, making them particularly well suited for compact sites, construction‑waste processing, and manufactured sand production. Mobile crushing stations significantly reduce capital investment while boosting returns. They are widely used in road and bridge construction, mining operations, and urban infrastructure projects.

　　Mobile sand-making plants feature a well‑balanced configuration of crushing and sand‑making equipment, smooth material flow along the entire production line, reliable operation, user‑friendly controls, and high efficiency with energy savings. In particular, they offer excellent mobility, can be relocated to match the source of raw materials or the construction site, and can be configured in various combinations to meet diverse material‑handling requirements.

　　● Impact crusher

　　The impact crusher utilizes the principle of impact crushing to reduce material size; it is a finer‑grinding machine than the jaw crusher and is primarily employed for fine crushing in aggregate production lines, often working in tandem with a jaw crusher. The impact crusher relies on impact energy to break down the feed material.

　　Performance characteristics of the impact crusher:

　　1. More effective for handling materials with high moisture content, effectively preventing material blockages.

　　2. Suitable for crushing harder materials while maintaining low energy consumption.

　　3. The discharge particle size can be conveniently and flexibly adjusted, with a wide adjustment range.

　　4. Low wear on consumable parts and high metal utilization rate

　　5. The impact crusher features easy replacement of spare parts, thereby reducing maintenance costs.

　　The rotor of the impact crusher is equipped with only six hammer plates, and a specially designed tool enables quick and convenient replacement. Replacing an entire set of hammer plates takes just one shift.

　　Impact crushers can process a wide range of coarse, medium, and fine materials—such as granite, limestone, concrete, river pebbles, basalt, iron ore, quartzite, and diabase—with maximum lump sizes not exceeding 500 mm and compressive strengths up to 350 MPa. They are extensively used in sand and gravel quarries, mining operations, coal mining, concrete mixing plants, dry-mix mortar production, power‑plant desulfurization, quartz sand processing, and other mineral‑crushing applications, as well as in the production of manufactured sand and gravel for railways, highways, and the construction industry.

　　● Rod mill sand-making machine

　　The rod mill sand-making machine is a highly efficient, energy-saving crushing and sand‑making equipment that consumes 50% less energy than conventional sand‑making machines. It is primarily used for processing and finely or moderately crushing a wide range of hard, brittle materials, including abrasives, refractory materials, cement, steel grit, slag powder, copper ore, iron ore, gold sand, concrete aggregates, asphalt aggregates, as well as mineral raw materials such as feldspar, quartz, and river pebbles. The cylindrical drum rotates at a specified speed; under the combined action of friction and centrifugal force, the grinding media rise to a certain height before being thrown down, subjecting the feed material to impact and attrition, thereby achieving the desired sand‑making effect.

　　Performance Characteristics of Rod Mill Sand Making Machines

　　1. Energy savings. Compared with older equipment, it saves more than 40% of energy.

　　2. Suitable for ores of varying hardness (Mohs hardness 5.5–12), resulting in more uniform product particle size and higher throughput.

　　3. The fineness of the discharged product is adjustable. 4. Rod mills for sand production are available in both dry and wet configurations, allowing users to select the option best suited to their specific needs. For processing products such as quartz sand, dolomite, and monazite, a magnetic separator can be installed downstream of the mill to remove iron.

　　● Cone Crusher
　　The cone‑type sand maker builds on the high‑efficiency crushing principles of cone crushers and incorporates multi‑cylinder hydraulic technology. Addressing the shortcomings of conventional vertical shaft sand makers in practical applications, and aligning with market demands for sand‑making equipment, it is a completely new‑concept machine independently developed through the application of proprietary patented technologies in product design, materials, and manufacturing processes. Unlike the traditional vertical shaft sand maker, which operates on the “stone‑on‑stone” principle, this cone‑type sand maker employs a “stone‑on‑stone” crushing mechanism to produce sand—shifting from “impact‑based” to “grinding‑based” sand production, thereby making the conversion of raw stone into sand both easier and more efficient. It is ideally suited for various artificial sand‑making applications in mining material production lines, as well as for metallurgical powder‑extraction equipment in diverse metallurgical mining operations.

　　As sand-making equipment continues to evolve, the application areas of different models have also diverged. Today, the most common type of sand-making machine on the market is the impact crusher.