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Hongzhi Measurement Instruments Hongzhi Measurement Instruments

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    Frequently Asked Questions

    If you cannot find the answer to your question in our FAQ, please feel free to leave us a message, and we will get back to you promptly.

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    Is the universal materials testing machine experiencing loading stalling or abnormal zeroing of load data?

    1. Loading lag: Clean the lead screw and guide rails, apply lubricant, and remove debris from the transmission components. 2. Zeroing anomaly: Restart the equipment system, calibrate the load and displacement zero points, and check for poor electrical contact in the sensor wiring. 3. Overloading is strictly prohibited; before testing, verify that the grips are securely tightened to prevent eccentric loading of the specimen.

    How often should in‑instrument verification be performed? Which instruments are required to undergo it?

    High-precision, high-frequency‑use, and drift‑prone equipment (such as balances, penetrometers, water permeability testers, and sensor‑type devices) shall undergo intermediate verification every three months; routine equipment shall be verified every six months. Equipment that is within the verification/calibration interval, has undergone repair following a malfunction, or has been relocated must undergo additional intermediate verification, with complete verification records maintained.

    Is the repeatability of pendulum-type pavement friction coefficient measurements poor?

    Key points for resolution: Prior to testing, thoroughly clean the pavement at each measurement point, ensuring there is no standing water, dust, or debris; calibrate the instrument’s level and zero point to ensure a standardized pendulum‑drop trajectory; strictly control the pendulum’s sliding distance; avoid conditions such as strong winds, wet pavement, or abrupt temperature changes; and calculate the average of multiple measurements taken at the same point.

    How should one handle cases where the pavement infiltration meter data exceeds allowable error limits, exhibits leakage, or shows abnormal readings?

    1. Sealing leaks: Inspect the base seal for aging or damage and replace it promptly; before testing, firmly press down on the base to expel any residual air inside. 2. Data deviation > ±2%: Calibrate the level sensor, clean any residue from the graduated cylinder, and check for damage to the scale markings. 3. Compliance with new regulations: When the seepage rate is ≤300 mL/min, existing equipment may continue to be used; when it exceeds 300 mL/min, the accuracy of older equipment fails to meet the standard, and such equipment must not be used.

    Can the old Marshall compaction apparatus and stability tester still be used?

    According to the 2025 revised asphalt testing procedures, after adjusting the plunger diagram of the Marshall stability test apparatus, existing in-service equipment may continue to be used without mandatory replacement; only periodic calibration to maintain accuracy and ensure proper equipment condition is required.

    What are the causes of uneven compaction and layered cracking in molded specimens during compaction testing?

    Main causes: non‑vertical drop of the compaction hammer, rail jamming, excessive deviation in hammer weight, uneven layer thickness during loading, insufficient number of blows, or overloading. Solutions: regularly lubricate the guide rails; verify and adjust the hammer’s vertical alignment; strictly follow the procedure for layered material placement and step‑by‑step compaction; confirm that hammer weight and drop height comply with standards; and prevent over‑thick layers from being placed.

    What causes drift in the readings and inaccurate data on soil moisture meters, and how can these issues be resolved?

    Core causes: probe contamination and oxidation, interference from stones, roots, or salts in the soil, insufficient insertion depth of the probe, uncalibrated equipment, and significant fluctuations in ambient temperature and humidity. Solutions: wipe the probe with a dry, soft cloth—do not wash it with water; select a homogeneous soil sample and insert the probe vertically to a depth of at least 5 cm; perform zero-point calibration before testing, and periodically re‑calibrate during batch tests, avoiding environments with high temperature, high humidity, or strong electromagnetic interference.
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