Overhead Conveyor Shot Blasting Machine

Product Overview

The overhead conveyor shot blasting machine (Q38/Q48/Q58 series) is a specialized piece of equipment designed for large-volume, continuous surface cleaning of medium to large-sized workpieces such as castings, forgings, welded parts, and heat-treated parts. Workpieces are suspended by hooks or special hangers on the overhead conveyor and continuously or in a step-by-step manner fed into the enclosed shot blasting chamber by a conveyor system. Multiple shot blasters propel projectiles at high speed from the sides and top at multiple angles. The workpieces rotate or oscillate within the blasting zone, achieving 360° all-around cleaning.

The equipment is available in three types based on the conveying method:

Continuous (Q38 series): The overhead conveyor runs continuously at a uniform speed, suitable for large batches of single-type or similar-sized workpieces;

Step-by-step (Q48 series): The overhead conveyor moves in a step-by-step manner, allowing workpieces to remain in the cleaning chamber for a longer period, suitable for high-level cleaning requirements or complex workpieces;

Accumulating (Q58 series): The overhead conveyor has an accumulation function, allowing pauses at designated stations, suitable for multi-type mixed-production lines and pre-coating treatment line integration.

Working Principle and Process Flow

Workpieces are suspended on a overhead conveyor using specialized hangers or hooks and fed into a closed shot blasting chamber by a drive system at a set speed (continuous) or rhythm (stepping/accumulating). Multiple shot blasters propel projectiles at high speed from different angles. The workpiece is impacted by the projectiles within the blasting zone, while the hook's rotation mechanism drives the workpiece to rotate, ensuring that all surfaces, including internal cavities and grooves, are fully blasted.

The projectiles are recovered by a scraper at the bottom of the chamber, conveyed by a screw conveyor, and lifted by a bucket elevator into an air separator for separation and recycling. Dust and broken shot are filtered by a pulse jet filter/bag filter system before being discharged in compliance with standards. After cleaning, the workpiece is conveyed out of the chamber via an overhead conveyor to the unloading area or subsequent coating/drying station.

Process Flow: Loading hanger → Overhead conveyor into chamber → Shot blasting (+ hook rotation) → Overhead conveyor out of chamber → Shot cleaning → Unloading/Transfer to coating

Core Configuration And Wear-Resistant Parts Standards

The shot blasting machine adopts a high-efficiency direct-drive structure, with a direct-drive motor and no belt drive. The impeller is 100% dynamically balanced (dynamic balance grade G6.3) to ensure vibration ≤4.5 mm/s at high speeds. The blades, shot distribution wheel, directional sleeve, and guard plates are all made of high-chromium wear-resistant cast iron, with a chemical composition conforming to ASTM A532 standard, a hardness ≥58 HRC, and a standard blade life of 2500–3000 hours.

Shot blasting machine: High-efficiency direct-drive type, with an optimized layout angle based on 3D simulation to ensure full surface coverage of the workpiece suspended by the overhead conveyor;

Overhead conveyor system: Forged chain or circular chain, adjustable chain pitch, variable frequency speed control for smooth operation; accumulating configuration with stop and release mechanisms;

Hooks/hangers: Custom-made hangers based on workpiece shape to ensure stable suspension and prevent collisions during rotation;

Chamber lining: High-chromium cast iron/65Mn rolled lining, modular quick-connect design, 10–20 mm thick, quick-replacement;

Sealing system: Multi-layer rubber curtains at inlet and outlet + labyrinth seal to prevent shot leakage;

Shot material circulation system: Bottom scraper recovery + screw conveyor + bucket elevator + air separation, separation efficiency ≥99%;

Dust removal system: Standard pulse jet cartridge dust collector (bag filter optional), dust emissions controlled to <5 mg/m³;

Electrical system: PLC Control (Siemens/Mitsubishi optional), touch screen operation, automatic adjustment of overhead conveyor speed, shot blasting volume, and hook rotation, with optional remote monitoring module.

Installation And Maintenance

Installation Site Requirements:

Q382 model: Approximately 12 m × 5 m footprint (including loading, main unit, and unloading areas); factory height ≥ 6 m;

Q384C model: Approximately 18 m × 6 m footprint; factory height ≥ 7 m;

Q488 model: Approximately 22 m × 8 m footprint; factory height ≥ 8 m;

Space must be reserved for the overhead conveyor rotation and workpiece placement; ≥ 3 m on each side is recommended;

Concrete foundation flatness ≤ 3 mm/m; anchor bolts must be pre-embedded in the main unit area and overhead conveyor support;

Power supply: 380V/3Ph/50Hz (or customized according to customer's power grid); a 20% margin in total equipment power is required.

Maintenance Points

Daily: Check the operating sound, vibration, and current of the shot blasting machine; check the smoothness of the overhead conveyor and the rotation of the hook; check the integrity of the sealing curtain;

Weekly: Check the wear of vulnerable parts (blades, guard plates) and replenish grease; check the tension of the hoist belt/chain;

Every 3–6 months: Conduct a comprehensive inspection of the chamber guard plates and overhead conveyor hook wear; check the position of the shot blasting machine's directional sleeve window; check the pressure difference of the dust collector filter cartridge/bag;

Blade Replacement Standard: Replace blades when wear >5 mm or cracks appear to ensure that the blasting speed does not decrease;

Overhead Conveyor Inspection: Check the chain elongation, pin wear, and lubrication. If the chain elongation exceeds 3%, it must be shortened or replaced;

Hook Inspection: Check the hook for deformation, cracks, and welds. Perform non-destructive testing (MT/PT) annually to ensure safe load-bearing capacity.

Global Service And Spare Parts Support

Jiuchang Machinery possesses independent import and export rights, offering various trade terms such as FOB/CIF/DDP, and supporting letters of credit, wire transfers, and milestone payments. Overseas installation services include a three-tiered model: remote technical supervision, on-site installation guidance, and turnkey projects. Global 24/7 response: over 80% of common faults can be resolved within 4 hours via remote diagnostics; local engineers arrive on-site within 48 hours. Commonly used spare parts from core market warehouses are delivered within 48 hours.

Applications

Scope Of Application

Suitable for batch surface cleaning of medium to large-sized metal workpieces such as cast steel, cast iron, forgings, welded parts, and heat-treated parts. Widely used in industries such as automotive manufacturing, motorcycle manufacturing, engine manufacturing, construction machinery, aerospace, rail transportation, valves and pipe fittings, and motor housings.

Typical workpieces: engine blocks, cylinder heads, crankshafts, gears, gearbox housings, valves, pump bodies, axles, bogies, brake discs, and welded steel structures.

Particularly suitable for:

High-volume, continuous production of automotive parts (e.g., cylinder blocks, cylinder heads, crankshafts, camshafts);

Castings with complex shapes, numerous internal cavities, and requiring 360° cleaning (e.g., gearbox housings, valves, pump bodies);

Automated surface treatment lines integrated with painting and drying lines (accumulation type Q58 series).

Not suitable for: Extra-large workpieces (single piece >1000 kg or size >Φ2000 mm, trolley type Q76 or hook type Q37 recommended); long strip pipes (roller conveyor type QZW recommended).