Introduction To Brake Pad Sandblasting And Operational Procedures

Brake Pad Sandblasting is a surface treatment process primarily used to clean brake pad surfaces (e.g., backing plates or friction material layers), removing oxidation, grease, rust, or other contaminants while increasing surface roughness. This enhances the adhesion of subsequent bonding (e.g., friction material to backing plate) or coatings. The sandblasting process significantly improves the durability and safety of brake pads and is a critical step in brake pad manufacturing or refurbishment.

Brake Pad Sandblasting Process

1. Pre-Treatment Preparation

 

- Surface Inspection: Check the brake pad surface for severe corrosion, grease, or residues.

- Cleaning and Degreasing: If grease or stains are present, thoroughly clean the surface using solvents (e.g., acetone, alcohol) or alkaline cleaners.

- Drying: Ensure the brake pads are completely dry to prevent moisture from affecting sandblasting results.

 

2. Sandblasting Equipment and Material Selection

 

- Sandblasting Machine Types: Common equipment includes pneumatic sandblasting machines and centrifugal wheel sandblasting machines.

- Abrasive Selection:

- Metallic Abrasives: Steel grit, aluminum grit (suitable for high-hardness surfaces).

- Non-Metallic Abrasives: Brown fused alumina, glass beads, ceramic sand (suitable for fine treatment to minimize substrate damage).

- Parameter Settings:

- Air Pressure: Typically 0.4–0.8 MPa (adjusted based on material).

- Blasting Angle: 45°–90° (vertical angles provide stronger cleaning force).

- Distance: 100–300 mm (avoid excessive wear from close proximity).

 

3. Sandblasting Operational Steps

 

1. Securing Brake Pads: Fix the brake pads onto the sandblasting machine workbench or fixtures to ensure stability.

2. Uniform Blasting:

- Apply blasting evenly across the surface according to set parameters, focusing on bonding areas or corroded regions.

- Avoid localized over-blasting to prevent substrate thinning or deformation.

3. Inspection:

- Post-blasting surfaces should exhibit uniform matte texture, with roughness meeting specific process requirements.

- Check for residual oxidation or uncleaned areas; rework if necessary.

Sampling Method: Randomly select a continuous batch from finished products.

Acceptance Criteria: Implement a "Zero Defect" policy.

 

Inspection Standards:

 

1. Appearance: No rust, burrs,凹凸 defects, visible scratches; blasted area >95%.

2. Time: 600±100 seconds.

3. Roughness: Ra 3–10 (both sides, 5 measurement points per side).

4. Batch Capacit*: 300–500 pieces per cycle.

5.*Operating Current: 40±5 A.

 

Inspection Guidelines:

 

All inspections and records must follow specified frequencies.

1. Appearance: Inspectors randomly check post-blasting products for rust, burrs, defects, scratches, and verify blasted area coverage >95%.

2. Blasting Time: Quality inspectors verify whether the equipment timer is within 600±100 seconds.

3. Roughness: Use a roughness tester to measure both sides of the backing plate, recording 5 points per side.

4. Batch Capacity: Inspectors randomly check if the per-cycle processing quantity is 300–500 pieces.

5. Operating Current: Inspectors confirm the equipment ammeter reads 40±5 A.

 

4. Post-Treatment

 

- Dust Removal: Use compressed air or vacuum systems to remove residual abrasives and dust.

- Protective Treatment:

- Apply rust inhibitors or phosphating for corrosion resistance.

- Proceed immediately to bonding processes (e.g., adhesive coating) to avoid contamination.

 

Application Scenarios

 

1. New Brake Pad Manufacturing: Enhances bonding strength between backing plates and friction materials to prevent detachment.

2. Refurbishment of Old Brake Pads: Removes aged layers to restore surface activity for re-bonding.

3.High-Performance Brake Pads: Increases mechanical interlocking force between friction materials and backing plates through surface roughening.