Density measurement may sound simple, but the national standard GB/T 1884 has clear regulations for each operational step. Omitting any step may lead to data distortion. Organizing the complete operational process, especially the details that are easily overlooked, helps standardize operations.

Step 1: Instrument preparation (bath solution must be injected before powering on)

Note 1 in the instruction manual: Water must be filled into the glass cylinder before powering it on. Add purified water or demineralized water to the cylinder until the liquid level is about 15cm from the upper cover. This step cannot be skipped, as dry burning with electricity will damage the heating element.

After turning on the machine, set the target temperature for the bath liquid, and wait for the constant temperature bath to reach and stabilize at the set temperature.

Step 2: Place the sample into the graduated cylinder

Pour the uniform sample slowly along the inner wall of the graduated cylinder, avoiding splashing and bubble formation. Tilt the graduated cylinder at about 45° to allow the liquid to flow slowly down the wall, which is a good way to reduce bubbles.

If there are bubbles gathering on the surface, gently touch the liquid surface with a piece of clean filter paper, and the bubbles will be adsorbed onto the filter paper and removed - do not stir with a stick, as that will only create more bubbles.

Sample volume: When measuring dark-colored samples using a metal graduated cylinder, the liquid level should be within 5mm of the upper edge of the cylinder to ensure sufficient liquid depth to float the densitometer and obtain accurate readings.

Step 3: Place the densitometer into the graduated cylinder

Place the graduated cylinder containing the sample vertically into the constant temperature bath of the HZMD-2001, ensuring that there is a space of at least 25mm between the bottom of the graduated cylinder and the bath bottom (to ensure that the densitometer can float freely without touching the bottom).

Gently place the petroleum densimeter into the sample, and after it stabilizes, press the densimeter down about two scales below the liquid surface, then release it:

Low viscosity sample: Gently rotate it when releasing it to help the densitometer float stably at a position away from the wall of the graduated cylinder

High viscosity sample: Wait for a sufficient amount of time for all bubbles to rise to the surface and escape, ensuring the densitometer is completely stationary

Step 4: Read the density value

When the densitometer is stationary and floating freely, align the line of sight horizontally with the upper edge of the meniscus on the liquid surface, and read the value at the point where the upper edge of the meniscus is tangent to the scale of the densitometer, accurate to 0.0001 g/cm³.

Simultaneously read and record the current sample temperature, which, along with the density value, serves as the basis for subsequent conversion to standard density.

Step 5: Input the instrument and print

Enter the "Measurement" interface, input the read density value and density unit using the buttons, press the "Save" button to save the record, and press the "Print" button to generate a paper report.