When investing in a sand and gravel production line, multiple factors such as production scale, capital, energy consumption, environmental protection, and subsequent maintenance costs will directly affect the operating costs of the entire production line. Currently, there is a wide range of crushing and sand-making equipment with various models. If the crushing and sand-making equipment can be reasonably selected and an excellent production line design process can be adopted according to the characteristics of the user’s raw materials, the operating efficiency of the entire production line will be significantly improved. Therefore, we have tailored an energy-saving and efficiency-enhancing solution for your company. The selection of sand and gravel equipment follows the principle of using advanced, reasonable, and reliable aggregate processing equipment to ensure that the quality of the finished sand meets the specification requirements and the production capacity of the sand and gravel equipment meets the project needs. On the premise of ensuring the quality of the finished aggregate and meeting the production capacity, equipment that is easy to operate and maintain later, has a relatively low unit price for sand and gravel processing, and a relatively low total investment is selected.
I. System Process Design
The system process design absorbs the mature experience at home and abroad. To flexibly adjust the sand and gravel production gradation and reduce the circulating load of the process flow, a segmented closed-circuit process flow is adopted for the sand and gravel processing system. The process design makes full use of the terrain conditions to achieve a compact and reasonable layout, reducing the occupied area and the amount of capital construction work, and lowering the project cost. A tailor-made energy-saving and efficiency-enhancing solution has been designed.
Key Process Explanation
- Overview of Process Flow Design
- The designed production capacity of the sand and gravel processing plant is 200T/h.
- The process design adopts a four-stage crushing, three-stage screening, and sand washing, dehydration, and recycling process.
- The four-stage crushing is: primary crushing (jaw fine crusher), secondary crushing (hydraulic cone crusher), fine crushing and sand making (compound sand making machine), and shaping and sand making (impact shaping machine).
- The three-stage screening is: pre-screening (feeder), primary inspection screening (vibrating screen), and secondary inspection screening (finished product vibrating screen).
- The sand washing, dehydration, and recycling equipment includes: sand washer, dehydration and recycling integrated machine.
- Explanation of the Advantages of Key Processes
- The process design of the sand and gravel production line is not randomly designed. Based on the characteristics of your company’s raw materials and combined with our company’s many years of on-site design experience, the process design makes full use of the terrain conditions to achieve a compact and reasonable layout, reducing the occupied area and the amount of capital construction work, and lowering the project cost. Generally, at the raw material feeding section of the sand and gravel production line site, a very high dock needs to be piled up to meet the elevation requirements for the raw material bin, vibrating feeder, and jaw crusher, resulting in difficulties in building the workshop and a large amount of capital and time investment in building the dock. This process adopts a combination of underground and above-ground installation methods, avoiding the capital and time investment in building the dock, and the installation of equipment underground also reduces the noise of the equipment. Each single crushing equipment is equipped with its own storage bin, and each equipment can feed evenly, avoiding the problem of large and small feeding amounts during equipment operation, reducing the workload of the operators, and enabling each equipment to work in good condition. Each sieve is equipped with a washing and spraying process, greatly reducing the dust at the site, improving the working environment at the site, and enhancing the quality of the stone materials. A reasonable process design is the premise for ensuring the smooth operation of the production line, a necessary condition for producing qualified products, and a prerequisite for maximizing the interests of customers.
- Process Flow Explanation
- Pre-screening and Primary Crushing Workshop
The raw materials are transported to the raw material bin by the transfer vehicle in the material yard. After pre-screening by the feeder, the materials larger than 40mm are fed into the PEX300×1300 jaw crusher. After primary crushing, they are transported to the transfer buffer bin by the belt conveyor. First, a ZSW4911 feeder / 1 unit (serial number 2) is selected for feeding and pre-screening. Materials less than or equal to 40mm can be directly transported to the primary screening vibrating screen (serial number 7) for screening to reduce the load of the primary and secondary crushing workshops. The primary crushing adopts open-circuit production, with a designed processing capacity of 200t/h. After crushing, it is directly transported to the transfer bin by the conveyor and then transported to the primary inspection vibrating screen by the conveyor for screening. The primary crushing equipment selects two PEX300×1300 jaw fine crushers / 2 units (serial number 3), with a single processing capacity of 100t/h. After the fine jaw crusher finishes crushing, it is transported to the transfer bin by the belt conveyor. The transfer bin feeder feeds, and the materials are transported to the primary inspection vibrating screen by the conveyor for screening.
- Secondary Crushing Workshop
The secondary crushing adopts closed-circuit production, with a designed processing capacity of 200t/h. After crushing, it is transported to the transfer bin by the conveyor. The transfer bin is transported to the primary inspection vibrating screen by the belt conveyor for screening. One HP300 multi-cylinder hydraulic cone crusher / 1 unit (serial number 12) is selected, with a single processing capacity of 110 – 440t/h, to crush the return materials from the primary inspection vibrating screen. The crushed materials are transported to the No. 1 transition bin by the belt conveyor to form a closed-circuit production.
- Secondary Inspection Screening
The primary inspection screening equipment is a 3YK2470 vibrating screen / 1 unit (serial number 7), with screen mesh specifications of 5mm, 10mm, and 40mm respectively. Materials larger than 40mm are returned to the HP300 cone crusher in the secondary crushing for continuous crushing through the conveyor to form a closed-circuit production. Materials of 5 – 40mm are transported to the shaping and sand-making VSI1145 through the conveyor for shaping and sand-making. Materials of 5 – 10mm are transported to the PFL1500 compound sand-making machine through the conveyor for sand-making. Materials of 0 – 5mm enter the lower receiving area of the primary inspection vibrating screen through water washing for centralized collection and then enter the end sand washing and recycling equipment.
- Fine Crushing Workshop
The fine crushing workshop adopts closed-circuit production, with a designed processing capacity of 30 – 80t/h. After crushing, it is transported to the secondary inspection screening equipment for inspection screening through the conveyor. One PFL1500 vertical compound sand-making machine / 1 unit (serial number 16) is selected, with a single processing capacity of t/h; it sands the return materials from the primary inspection screening and the secondary inspection screening. Through the optimized design of the rotor part and the crushing cavity of this machine, a multi-stage continuous crushing cavity is formed, making full use of energy and space, thus achieving sand-making for the materials and improving the performance of the machine.
- Shaping Part Process
The shaping and sand-making part adopts closed-circuit production. After shaping and sand-making, it is transported to the secondary inspection screening equipment for inspection screening through the conveyor. Combined with your company’s requirements for the finished product particle shape, we select one VSI1145 shaping sand-making machine / 1 unit (serial number 19) to crush, shape, and sand the return materials from the primary inspection screening and the secondary inspection screening. By repeatedly circulating and impact-crushing the oversized graded materials, the shaping of the materials and the increase in the production capacity of fine sand are achieved.
- Secondary Inspection Screening
The secondary inspection screening equipment is the finished product screen, which consists of one 4YK2470 vibrating screen (serial number 22), with screen mesh specifications of 5mm, 10mm, 20mm, and 31.5mm respectively. Materials of 5 – 31.5mm and other oversized and redundant materials are returned to the VSI1145 impact sand-making machine through the conveyor for continuous shaping and sand-making to form a closed-circuit production. Materials of 5 – 10mm are returned to the PFL1500 compound sand-making machine through the conveyor for continuous sand-making to form a closed-loop production. Materials of 0 – 5mm enter the lower receiving area of the secondary inspection screening vibrating screen through water washing for centralized collection and then enter the end sand washing and recycling equipment. Materials of 5 – 10mm, 10 – 20mm, and 20 – 31.5mm are transported to the finished product bin by the finished product conveyor;
- Sand Washing, Recycling, and Dehydration Part
The sand washing and recycling equipment consists of two LS1570 single spiral sand washers (serial number 24, 23) and two 1530 high-frequency vibration dehydration and recycling machines (serial number 9). One is used for the sand washing and recycling of the natural sand screened out by the primary inspection vibrating screen, and the other is used for the sand washing and recycling of the 0 – 5mm fine sand discharged from the crushing, sand-making, and shaping processes. Materials of 0 – 5mm and the washing water of the vibrating screen flow through the lower collecting hopper of the vibrating screen to the sand washer for sand washing, dehydration, and recycling.
- Process Planar Layout
- Fully combine the terrain and geological conditions within the site to reduce the occupied area, meet the needs, ensure the reliable operation of the system, and reduce the investment;
- Make full use of the favorable terrain to shorten the process flow route and simplify the transportation process;
- Use the existing site to achieve a compact layout, reduce the system excavation workload, and shorten the process flow line;
- The production auxiliary facilities are arranged nearby for convenient production operation and management;
- For the convenience of construction and operation management, roads are considered to be connected between each workshop;
- The highway layout should ensure convenient material loading and unloading, equipment maintenance, and smooth transportation.
II. Advantages of Reasonable Equipment Selection and Configuration
According to the process flow of the processing system and the results of the process flow balance calculation, considering the type and hardness of the materials, the raw materials for this customer are river pebbles, which have the characteristics of small particle size, many broken materials, high hardness, and difficult crushing. The main equipment to be configured in each workshop of the sand and gravel processing system is as follows:
- Advantages of Equipment Selection for Pre-screening and Primary Crushing
- For pre-screening, a ZSW1149 bar feeder is reasonably selected. The bar feeder can play a role in pre-screening, reducing the over-crushing of broken materials and the wear of equipment wear-resistant parts, improving the throughput per unit time of the production line, and reducing energy consumption. To reduce the load of the primary and secondary crushing workshops.
- For primary crushing, open-circuit production is adopted. Because the PEX300×1300 jaw fine crusher has a narrow and long inlet and outlet, it is more in line with the crushing characteristics of the customer’s raw materials with small particle size, and can further improve the crushing ratio of the raw materials. The longer discharge port can also improve the throughput per unit time.
- Advantages of Equipment Selection for Secondary Crushing
- The secondary crushing adopts closed-circuit production. After crushing, it is transported to the primary inspection screening equipment for inspection screening through the conveyor. One HP300 multi-cylinder hydraulic cone crusher / 1 unit is selected. The working principle of the multi-cylinder hydraulic cone crusher is laminating crushing, with good discharge particle shape. The wear-resistant parts have a longer service life compared to the impact crusher and hammer crusher, reducing the equipment maintenance times, downtime, and operating costs of the equipment.
- Advantages of Equipment Selection for Screening
- The primary inspection screening equipment is a 3YK2470 vibrating screen for 1 unit, and the secondary screening equipment is a 4YK2470 vibrating screen for 1 unit. The vibrating screen in our company’s production line is a new type of screening equipment with a circular vibration trajectory, which is specially designed for screening stone materials in quarries. This vibrating screen has the characteristics of advanced structure, strong excitation force, low vibration noise, easy maintenance, and durability. The output and energy consumption of the vibrating screen produced by our company meet the national standards and are at the advanced level at home and abroad, and are well received by users in various industries. Structurally, it adopts a cylindrical eccentric shaft exciter and eccentric blocks to adjust the amplitude. The advanced rivet-connected assembled frame structure improves the service life of the equipment, and the spring shock-absorbing device reduces the impact on the foundation. It is a multi-layer and efficient new type of vibrating screen. This model has a long material screening line, multiple screening specifications, clear screening of each specification, high screening efficiency, and is not easy to be blocked. It has the advantages of reasonable structure, strong excitation force, low vibration noise, durability, easy maintenance, and safe use, and is an ideal equipment for the crushing and screening unit. We also install a spraying system on the vibrating screen, which can effectively reduce the dust at the working site and greatly improve the working environment.
- Advantages of Equipment Selection for the Sand-making Part
- Considering that the customer has a small demand for 5 – 10mm stones, for the sand-making part, we select a vertical compound sand-making machine to make 5 – 10mm stones into sand to meet the customer’s large demand for sand. The compound sand-making machine has the characteristics of large crushing ratio, strong crushing ability, and diverse crushed materials. It integrates primary crushing and fine crushing, simplifies the process, and has a special structure, stable operation, low noise, and easy maintenance. It is a typical equipment in sand-making equipment. The PFL compound sand-making machine produced by our company has a high output. Its sand-making process is a through-type sand-making, with a fast passing speed. Therefore, relatively speaking, the output is high, the energy consumption is less, it is more efficient and energy-saving. The wear-resistant parts are made of high-hardness and high-toughness multi-alloy wear-resistant materials, with less wear and long service life. The distance between the hammer head and the counter plate can be finely adjusted to ensure uniform product particle size. The hammer head can be used reversely, greatly improving the utilization rate of the hammer head and increasing the service life by about 5 times. Through the optimized design of the rotor part and the crushing cavity of this machine, a multi-stage continuous crushing cavity is formed, making full use of energy and space, thus improving the performance of the machine.
- Advantages of Equipment Selection for the Shaping and Sand-making Part
- Combining your company’s need for higher-quality finished sand and gravel, we select one VSI1145 shaping sand-making machine / 1 unit to crush, shape, and sand the return materials from the primary inspection screening and the secondary inspection screening. By repeatedly circulating and impact-crushing the oversized graded materials, the shaping of the materials and the increase in the production capacity of fine sand are achieved.
The shaping sand-making machine is a commonly used sand-making and shaping equipment for river pebbles. It can impact the flaky and strip-shaped crushed stones from the cone discharge to be more round, improving the production capacity of the machine-made sand. The finished product is cube-shaped, with full particle shape, relatively uniform particle size, reasonable gradation, very simple operation and maintenance, and good sand-making effect.
- Advantages of Equipment Selection for the Sand Washer and Fine Sand Recovery Part
- For the sand washing part, we select two 1570 single spiral sand washers. One is used for the sand washing and recycling of the natural sand screened out by the primary inspection vibrating screen, and the other is used for the sand washing and recycling of the 0 – 5mm fine sand discharged from the crushing, sand-making, and shaping processes. Selecting a single spiral sand washer has less sand washing loss and less water consumption during operation, can save a lot of energy, and can clean more thoroughly.
- For the fine sand recovery part, we select two 1530 fine sand recovery machines that are配套 with the two spiral sand washers, improving the fine sand recovery rate. It saves resources, is more environmentally friendly, and realizes the screening and application of waste materials. The fine sand recovery machine produced by our company has strong production capacity, stable operation, good performance, easy maintenance, few faults, and a compact structure. The wear-resistant parts are all high-quality wear-resistant accessories produced by first-line brand manufacturers.
The above is the specific energy-saving and efficiency-enhancing solution and reasonable equipment selection customized by our company for your company. Our company always adheres to the principle of only choosing the right equipment, not the expensive one, and ensures that the finished sand and gravel have excellent particle shape. Please review the advantages of the advanced process flow design, correct equipment selection, and technical properties of the aggregate and sand of this production line.
Henan Shaolin Heavy Machinery Co., Ltd.
