What type of automatic sandblasting machine do auto parts manufacturers choose?

When purchasing automatic sandblasting machines, auto parts manufacturers should make comprehensive judgments based on the material characteristics of parts, processing requirements (such as rust removal, deburring, surface strengthening, etc.), production scale and accuracy requirements, so as to avoid inefficiency or parts damage caused by mismatch between equipment and actual scenes. The following three aspects, namely, the core purchase dimension, common types of adaptation scenarios, and key points for attention, help to accurately select the type:

First, make clear the three core purchase preconditions (avoid blind selection)

Before determining the type of sandblasting machine, it is necessary to sort out its own processing requirements, which is the basis of selection:

Basic attributes of parts

Material: aluminum alloy, cast iron, stainless steel, plastic and other materials have different tolerance to sandblasting media (abrasive) (for example, aluminum alloy should not use high-hardness abrasive to avoid surface scratch);

Size/weight: Small parts (such as bolts and sensor housings) and large parts (such as frame and gearbox housing) need to match the sandblasting machine working cabin/transportation mode with different sizes;

Structural complexity: Parts with deep holes and grooves (such as engine cylinder block) need to consider the "dead angle covering ability" of sandblasting machine (such as multi-gun layout and rotating workbench).

Core processing requirements

Different demands correspond to different sandblasting machine functions, and it is necessary to make clear whether it is a single demand or a compound demand:

Requirements of core purpose of processing requirements on sandblasting machine

Derusting/descaling removes surface rust of parts, and the abrasive hardness of heat treatment oxide layer is moderate (such as steel shot and brown corundum), and the pressure is stable.

Deburring/flash cleaning tiny burrs (such as the edge of valve body) after stamping and die casting, fine abrasive (such as ceramic sand and plastic sand), and accurate pressure control.

Surface strengthening (shot peening) to improve the fatigue strength of parts (such as springs and transmission gears) needs to support "controllable shot peening strength" (if it meets SAE J442 standard).

Surface roughening/pretreatment prepares for painting and coating (such as body panel). The surface roughness is uniform (Ra value is controllable).

Cleaning residual impurities (such as mold release agent) can be combined with cleaning function to remove mold release agent and oil stain on the surface of die-casting parts, and the abrasive is not easy to stick.

Production scale and automation requirements

Small batch/multi-variety: give priority to "high flexibility" equipment (such as manual+automatic switching and quick tooling replacement);

Large batch/single variety: it is necessary to select "high automation+high capacity" equipment (such as assembly line and continuous conveying) to reduce manual intervention;

Rhythm requirement: It is necessary to calculate the "single part sandblasting time" to ensure that the equipment capacity matches the production line rhythm (for example, 1 minute/piece vs 30 seconds/piece).

Two or four kinds of mainstream automatic sandblasting machine adaptation scenarios (classified according to the processing requirements of automobile parts)

In the processing of auto parts, the following four types of automatic sandblasting machines are the most widely used, and they need to be selected according to the above premise:

1. Rotary automatic sandblasting machine (adaptation: small/medium-sized parts, multi-variety and small batch)

Structural features: There are 1-more rotating turntables in the working cabin, the parts are fixed on the turntables, and sandblasting guns are arranged around them (the angle and pressure of the spray guns can be set), which can automatically complete 360 sandblasting.

Adapted parts: bolts, nuts, sensor housings, small gears, bearing seats, car buckles, etc.

Core advantages:

Convenient tool replacement (adapting to parts with different sizes) and high flexibility;

Sand blasting is even, without obvious dead angle (turntable rotation+multi-gun layout);

Small floor space (suitable for manufacturers with limited workshop space).

Note: the number of parts processed at one time is limited, which is not suitable for super-large parts.

2. Crawler automatic sandblasting machine (adaptation: small/bulk parts, continuous processing in large quantities)

Structural features: Parts (such as steel crawler and rubber crawler) are transported by crawler, and the parts enter the sandblasting cabin with the crawler, and are sandblasted by top/side spray guns, and then automatically discharged after completion, which can be connected to the production line.

Adapted parts: screws, gaskets, small stamping parts, bearing rollers, automobile hardware (such as door handle components).

Core advantages:

Continuous transportation, high productivity (can work continuously for 24 hours);

No need for manual clamping (bulk parts are directly poured into the feed inlet), saving labor;

Optional "automatic sorting device" (separating parts from abrasives) can reduce subsequent cleaning.

Note: the track material should match the parts (for example, rubber tracks are suitable for parts that are afraid of collision, and steel tracks are suitable for high-hardness parts); Parts are easy to accumulate, so it is necessary to control the feed rate to avoid uneven sandblasting.

3. robotic automatic sandblasting machine (adaptation: complex structure/large parts, high precision requirements)

Structural features: equipped with 6-axis/multi-axis robot, the spray gun is installed on the robot arm, which can accurately fit the curved surface, deep hole and groove of the part according to the preset program (CAD model import) and realize the "customized sandblasting path".

Adapted parts: engine block, gearbox housing, frame parts, car seat frame, exhaust pipe (with complex curved surface or deep hole).

Core advantages:

The coverage rate of dead angle is over 95% (such as the oil passage hole of the cylinder body and the inner cavity of the shell);

Sand blasting accuracy is extremely high (pressure, angle and distance can be adjusted in real time, which is suitable for parts with strict surface roughness requirements);

It can be connected with MES system to realize the integration of automatic production line (such as linkage with pre-sequence processing and post-sequence detection).

Note: the initial investment cost is high, which requires professional programming and debugging; Suitable for large and medium-sized manufacturers or high-precision machining requirements (such as motor housing of new energy vehicles).

4. Pass-through automatic sandblasting machine (adaptation: long strip/large parts, mass assembly line processing)

Structural features: Conveyor belts (such as roller conveyor and chain conveyor) are used to "pass through" the sandblasting chamber, and spray guns are arranged according to the shape of the parts (such as top, two sides and bottom), which is suitable for continuous processing of long or large parts.

Adapted parts: automobile door frames, window frames, long shaft parts (such as transmission shafts), shock absorber housings, and large supports (such as chassis supports).

Core advantages:

Can match the production line rhythm (feeding-sandblasting-discharging is fully automatic, without manual transshipment);

Flexible processing size (the conveying bandwidth and the length of sandblasting chamber can be customized, and it is suitable for long parts exceeding 10m);

Optional "secondary dust removal system" (reducing workshop dust and meeting environmental protection requirements).

Note: the equipment occupies a large area (space for conveying line needs to be reserved); It is necessary to ensure that the parts do not shake during transportation (fixed by customized tooling).

Three, five key points for attention when purchasing (avoid stepping on the pit)

Abrasive compatibility: matching parts material+processing requirements.

The wrong choice of abrasive will cause damage to parts or the effect will not meet the standard, so it needs to be selected according to "material-demand". Common abrasive adaptation:

It is recommended that abrasives be prohibited/used with caution for the processing requirements of parts materials.

Aluminum alloy and magnesium alloy deburring and roughening ceramic sand, glass beads, plastic sand brown corundum, steel shot (high hardness and easy to scratch)

Cast iron, stainless steel derusting, reinforced steel shot, steel sand, brown corundum plastic sand (insufficient hardness and low efficiency)

Plastic and rubber parts shall be deburred, and any high-hardness abrasive (easily broken) such as nylon sand and walnut sand shall be cleaned.

Environmental protection and safety: in line with industry standards

Auto parts processing is mostly in industrial areas, which need to meet the requirements of environmental protection:

Dust removal system: choose "high-efficiency bag dust collector" or "pulse dust collector" to ensure that the dust emission concentration is ≤ 10 mg/m (in line with GB 16297 standard);

Noise control: the operating noise of the equipment is less than or equal to ≤85dB (adding sound insulation cover and shock absorption pad to avoid affecting the workshop environment);

Safety protection: the sandblasting cabin should have the functions of "emergency stop button" and "opening the door and cutting off power" to prevent abrasive splashing from injuring people.