Technical Parameters

Penetration timing control device: Adjustable from 1 to 99 seconds; timing error is less than ±0.1 second.

Penetration depth device: Uses a high-precision displacement sensor for digital display conversion, making operation convenient, fast, and intuitive; it can be started at any position.

Penetration accuracy: ±1 penetration unit

Maximum penetration depth: 600 penetration units

Constant-temperature bath: Made of hard glass

Standard needle: 2.5 ± 0.05 g, conforming to the requirements of GB/T 4509 and T0604

Standard needle assembly: 100 ± 0.05 g, conforming to the requirements of national standard GB/T 269

Lifting bracket: Can be adjusted manually for easy alignment of the needle tip with the sample surface

What is it used for?

he computerized asphalt penetration tester is a specialized instrument used in highway/municipal laboratories that automatically measures asphalt penetration (the depth a standard needle sinks into asphalt under conditions of 25℃, 100g load, and 5 seconds, in units of 0.1mm) in accordance with national standards. It is used to determine the grade, hardness, consistency, and high-temperature stability of asphalt, serving as core testing equipment for the three major indicators of asphalt (penetration, softening point, and ductility).

I. Core Purpose

Test object: Road petroleum asphalt, modified asphalt, emulsified asphalt residue, cutback asphalt, etc. Test indicator: Penetration (P) – reflects the consistency/hardness of asphalt at room temperature; the higher the value, the softer the asphalt, and vice versa. Engineering significance:

• Determine asphalt grade (such as 70#, 90#, 110#, classified by penetration range);
• Control construction quality: verify the qualification of incoming asphalt and check the compatibility of mixing/paving temperatures;
• Calculate penetration index (PI): evaluate the temperature sensitivity of asphalt;
• Indicate high-temperature stability: indirectly predict risks such as pavement rutting in summer and cracking in winter.

II. Working Principle

1.Sample preparation: Heat and melt asphalt → pour into standard mold → cool → thermostatically bath at 25℃±0.1℃ for 1~1.5 hours;

2. Instrument setting: Computer-controlled temperature (25℃), time (5s), and load (total weight 100g: standard needle + needle rod + weight);

3.Automatic test: Reset when needle tip touches sample surface → one-key release → automatic stop after 5s → read sinking depth (accurate to 0.1mm) → test 3 points and take the average;

4.Data output: Automatically calculate penetration and PI, generate reports, print or export data.

III. Differences Between Computerized and Ordinary Models

✅ Fully automatic: Computer-controlled temperature, timing, reading and calculation, reducing human error;

✅ High precision: Displacement accuracy 0.01mm, temperature control ±0.1℃, complying with standards such as JTG 3410-2025, GB/T 4509, ASTM D5;

✅ Intelligent data: Automatically calculate PI, save records, connect to computers/printers, suitable for construction sites, quality inspection stations and research institutes.

IV. Key Parameters

• Standard conditions: 25℃, 100g, 5s;
• Unit: 0.1mm (e.g., penetration of 70# asphalt is 60~80, meaning 6.0~8.0mm);
• Applicable standards: JTG 3410-2025 (Highway), GB/T 4509 (National Standard).

V. Summary

It is a core testing instrument essential for highway engineering used to measure asphalt hardness, determine grades, control quality, and prevent pavement diseases.