How To Check The Quality of LVT/SPC Flooring--Needle Scratch Tester

Purpose

The needle scratch tester is used to evaluate the ability of flooring surfaces (such as coated or painted layers) to resist scratching under a specified load.
It helps determine the durability and scratch resistance performance, simulating real-life conditions such as furniture dragging or sand abrasion.

Equipment Structure

Weight loading system (upper part)

A cylindrical weight is applied to provide a constant load.

Metal needle (middle part)

Used to create scratches on the sample surface. 

Movable sample platform (lower part)

Allows the needle to move linearly across the material surface.

Control system

Includes speed/length adjustment knobs and a power switch to control the testing process. 

Test Preparation

1. Sample Preparation

    Size: Typically ≥ 100 mm × 100 mm 

    Surface: Clean, free of dust and oil

    Condition: No visible defects such as bubbles or pre-existing scratches

2. Environmental Conditions

    Temperature: 23 ± 2 °C

    Humidity: 50 ± 5% RH

    Conditioning time: ≥ 24 hours before testing

3. Equipment Isnpection

    Ensure the needle tip is intact and not worn

    Calibrate the applied load

    Confirm the machine operates at the correct speed

Test Procedure

Step 1: Fix the Sample

Place the flooring sample on the test platform:

• Ensure it is flat without warping

• Fix it firmly to prevent movement

Step 2: Set Test Parameters

Adjust according to standards or customer requirements:

Load: e.g., 5N / 10N / 20N

Scratch speed: typically 5–50 mm/s

Scratch length: e.g., 50 mm or 100 mm

Needle type: metal needle (commonly steel or carbide)

Step 3: Apply the Load

Place the weight on the loading rod so that the needle contacts the sample surface with a constant force.

Step 4: Start the Test

Turn on the machine and allow the needle to move across the sample surface in a straight line, forming a continuous scratch.

Multiple scratches can be made on each sample.

Step 5: Repeat Testing

Repeat the test under different loads or at different positions to ensure reliable results.

Result Evaluation

1. Visual Inspection (Common Method)

Observe the scratch condition:

Whether obvious white marks appear

Whether the wear layer or UV coating is damaged

Whether the substrate is exposed

Typical Ratings:

No visible scratch: Excellent

Slight mark: Acceptable

Obvious damage: Not acceptable

2. Microscopic Measurement (Advanced Method)

• Measure scratch width and depth

• Record the critical load at which visible damage occurs