Mesh Belt Shot Blasting Machine for Leaf Springs

This model is a continuous web-belt pass shot blasting cleaning machine, specifically customized for commercial vehicles, heavy-duty trucks, and trailer suspension leaf

springs (plate springs). It is designed in collaboration with professional large-scale plate spring manufacturers and serves as a core standardized surface treatment unit

positioned between the heat treatment process and the painting or precision machining stages for leaf springs. Leveraging a continuous automated web-belt conveying

system, this machine enables uninterrupted, line-type shot blasting operations on workpieces, effectively meeting both the dual requirements of surface rust removal, slag

removal, and mechanical stress strengthening; thus, it represents a standard essential piece of equipment for modern mass production lines for leaf springs.

The client in this collaboration primarily manufactures various types of automotive single-piece steel leaf springs; the specific parameters for the workpieces awaiting

processing are as follows:

External dimensions: The leaf spring width is controlled within 70–100 mm; the span of a single leaf is 1200–2500 mm; and the plate thickness range is 8–18 mm.

Workpiece geometry: A long, curved plate-shaped structure; the workpiece is pre-formed through stamping to incorporate assembly positioning holes; the incoming

material has undergone high-temperature heat treatment, resulting in a thick layer of black oxide scale and corrosion deposits on its surface. The workpiece exhibits high

dimensional accuracy and strong stability when laid flat, making it highly suitable for flat-sheet conveying operations using mesh belts.

The core benefits this equipment brings to customers

• The fully automated continuous operation replaces traditional manual sandblasting and intermittent hook-based shot blasting processes, significantly reducing the need for manual supervision, substantially enhancing production efficiency, and meeting customers' demands for large-scale mass production;

• The surface treatment process exhibits high standardization and consistency; the cleanliness level and surface strengthening stress parameters of each leaf spring are stable and controllable, effectively reducing the failure rate of fatigue fracture in finished products after installation;

• The entire system features a compact design, enabling seamless integration into the customer's existing complete heat treatment and coating production line; it occupies minimal workshop space, boasts a mature and stable structure, and allows for simple and convenient routine maintenance and spare part replacement in the later stages of operation.

Equipment specifications:

I. Configuration of the feeding and discharging conveyor belt system

1. Feed section conveyor belt: 2 m

At the feed end, a high-strength wear-resistant load-bearing mesh belt conveyor platform with a total length of 2 meters is installed; its primary functions are:

• This process involves receiving material from the preceding stage; operators or automated robotic arms can then steadily lay out the formed leaf springs flat, reserve sufficient space for material feeding operations, arrange the workpieces neatly, and prevent workpiece stacking or misalignment;

• The conveyor belt features a high-load-bearing manganese steel woven structure, designed to accommodate curved leaf springs with widths of 70–100 mm, thicknesses of 8–18 mm, and relatively high individual self-weight; during the conveying process, it provides slip-resistant and offset-prevention capabilities, enabling the smooth and steady transport of workpieces into the shot blasting chamber of the main machine at a constant speed;

• The feeding section is equipped with a simplified guiding and limiting structure that prevents the plate spring conveyor from lateral displacement during operation, thereby ensuring the workpiece enters the shot blasting effective processing zone with high precision.

2. Product discharge section conveyor belt: 2 m

The discharge end is equipped with a 2-meter finished product conveying web belt:

• After completing shot blasting strengthening and rust removal treatments on the leaf springs, the processed workpieces are uniformly discharged from the enclosed cleaning chamber at a constant speed; staff can then conduct centralized inspection of the surface treatment quality at the discharge zone and transfer the parts to the next coating or flaw detection process;

• The discharge section synchronously collects a small amount of falling steel balls, preventing them from scattering across the workshop floor; it is equipped with side material containment guards to prevent workpieces from rolling off and steel balls from leaking out.

• The entire feeding and unloading web belt system shares a single variable-frequency drive system; its conveying speed is continuously adjustable, allowing for flexible speed tuning based on production capacity requirements ranging from 4,000 to 10,000 sheets/day, thereby ensuring synchronization with the overall plate spring production line's cycle time.

II. Shot blasting equipment: 11 kW high-efficiency direct-drive shot blasting machine × 4 units

Hardware Basic Parameters

The rated power of each shot blasting unit is 11 kW; the entire system is equipped with 4 high-precision centrifugal shot blasting units arranged in a symmetrical three-

dimensional staggered configuration, specifically designed to provide comprehensive shot blasting coverage for both the front and back surfaces, side edges, and

installation holes of curved plate springs without any blind spots.

Process Compatibility Advantages

Power matching conditions for customer-ordered leaf springs with thickness ranges of 8–18 mm:

• 8 mm thin plate spring: By reducing the motor operating frequency and lowering the steel shot projection velocity, this approach enables simultaneous oxidation

  scale removal while preventing the curved plate from undergoing deformation due to high-intensity impact;

• 18 mm heavy-duty leaf spring: designed for full-power operation to ensure sufficient impact kinetic energy, thoroughly remove the high-temperature oxide layer

  resulting from heat treatment, while simultaneously forming a uniform compressive stress layer on the surface of the plate to achieve shot blasting strengthening

  and enhance material quality.

Layout advantage: The four shot blasting units are arranged in upper and lower positions, covering the upper surface, lower arc surfaces, and both side edges of the plate

spring; this design resolves the issue of inadequate cleaning on a single side of the curved structure. It ensures uniform roughness and stress distribution across the entire

workpiece, thereby consistently achieving the SA2.5 rust removal grade and meeting the fatigue strengthening process requirements.

For structural reliability, the shot blasting machine's blower blades, impeller, and directional sleeve are all fabricated from high-chromium wear-resistant materials, ensuring

low wear rates when impacting high-strength steel shot over long-term operation; the motor employs a direct-drive transmission structure, which offers high transmission

efficiency and a low failure rate, making it suitable for all-weather continuous mass production (with a maximum daily output of 10,000 parts without interruption) and

ideal for two-shift operations in leaf spring manufacturing plants.

The air flow rate and blasting volume can be independently fine-tuned; each of the four shot blasting units can be started or stopped individually, with zone-specific power

regulation; during small-batch production, specific units can be selectively activated to conserve electrical energy and reduce steel shot consumption.

III. Dust removal and purification system configuration: 11 kW fan paired with a 12-stage filter cartridge pulse-jet dust removal unit

Main induced draft fan: Rated power 11 kW

The 11 kW high-voltage centrifugal induced draft fan provides negative suction force for the entire dust removal system, creating a stable negative pressure environment within the shot blasting enclosed chamber:

• During the operation process, real-time suction is applied to remove rust dust, oxide scale particles, and fine crushed steel shot powder generated by the shot

  blasting process; this prevents any dust from spilling out through the equipment's feeding or discharge ports, thereby maintaining a clean workshop operating

  environment;

• The negative pressure airflow is precisely calibrated to ensure that qualified steel balls are not drawn into the dust removal system; it only removes lightweight dust

  particles and impurities, thereby minimizing unnecessary loss of qualified steel balls to the greatest extent possible;

• The fan's variable frequency drive allows for adjustable speed control, enabling it to automatically match the wind pressure to the equipment's operating

  conditions, while reducing the rotational speed during no-load standby mode to achieve energy-efficient operation.

Host filtration unit: 12 filter-tube type pulse-jet dust collectors

• The system is equipped with a total of 12 high-efficiency coated polyester dust collection cartridges; each individual cartridge provides an ample filtration area,

  and the total filtration airflow capacity perfectly matches the dust generation volume produced when four 11 kW shot blasting machines operate in

  synchronization.

• Equipped with an automatic pulse-blowing dust removal system that automatically compresses air to blow away accumulated dust from the filter cartridge surface

  according to a preset cycle, eliminating the need for frequent manual disassembly and cleaning, thereby ensuring long-term unobstructed airflow and stable dust

  removal efficiency;

• The dust is uniformly collected at the bottom ash collection drawer; periodic centralized removal is sufficient. The entire system complies with local environmental

  protection standards for exhaust gas dust emissions, eliminates unorganized dust emissions, and meets the environmental impact assessment requirements for

  routine factory operations;

• The integrated unit is mounted on the side of the main equipment; it features a compact design, requires no significant additional workshop space, and offers simple installation and wiring procedures.

IV. Summary of the comprehensive compatibility analysis for the complete configuration designed for this leaf spring workpiece

• A 2-meter-long web belt on both the front and rear sections forms a complete automated feeding and unloading production line, enabling convenient loading and

  unloading without requiring complex fixture positioning, and perfectly compatible with the flat continuous conveying of long curved leaf springs;

• The 4-unit 11 kW shot blasting system offers ample power capacity, enabling it to implement a dual-process approach that combines deformation prevention for

  thin parts with intensive cleaning for thick parts, thereby meeting the customer's flexible production capacity requirements ranging from 4,000 to 10,000

  pieces/day;

• The 11kW negative-pressure fan combined with a 12-cylinder pulse-jet dust collector forms a closed-loop environmental protection dust removal system that

  prevents dust leakage during the production process, ensures continuous and stable equipment operation, reduces maintenance workload, and is highly

  compatible with the mass-production automated assembly line scenarios typical of leaf spring specialty manufacturers.