Μετρητής φαινόμενης πυκνότητας
Μετρητής φαινομενικής πυκνότητας – Μέθοδος Α του προτύπου ASTM D1895
Ογκομετρητής πυκνότητας χύδην υλικού
Συσκευή μέτρησης πυκνότητας χύδην υλικού
Εξοπλισμός μέτρησης της πυκνότητας χύδην
Μέτρηση φαινόμενης πυκνότητας και μέτρηση όγκου πυκνότητας
ASTM D1895, Μέθοδος Α

Μετρητής φαινομενικής πυκνότητας – Μέθοδος Α του προτύπου ASTM D1895 - Precision Bulk Density Measurement:

ASTM D1895 Method A is used to determine the apparent (bulk) density of finely sized plastic materials that flow easily through a narrow orifice. The method quantifies how a particulate material packs under gravity when discharged through a standardized funnel into a calibrated cup.

Συσκευή

• QPI‑BDM1800A Bulk Density Meter, designed according to ASTM D1895 Method A requirements:

  • Funnel orifice: 9.5 mm diameter (small‑opening design for free‑flowing powders and micro‑granules).

  • Receiving cup: 100 cm³ precision‑machined volume.

  • Rigid frame: ensures fixed alignment between funnel and cup.

  • Leveling base: adjustable feet for horizontal setup.

• Analytical balance: resolution ± 0.01 g.

• Sample handling tools: scoop, spatula, brush.

Principle of Operation

A free‑flowing powder or fine granular material is allowed to pass through the small‑diameter funnel under gravity. The material fills a calibrated cup without vibration or compaction. The mass of the material occupying the known volume is used to calculate bulk density.

Test Procedure

1. Instrument Preparation

• Ensure the QPI‑BDM1800A is clean, dry, and free of residual material.

• Level the base using the adjustable feet and a spirit level.

• Confirm that the funnel outlet is centered directly above the receiving cup.

2. Sample Conditioning

• Bring the sample to standard laboratory temperature (typically 23 ± 2 °C).

• Break apart soft agglomerates by hand without grinding or altering particle size.

3. Filling the Funnel

• Close the funnel outlet using the supplied shutter or flat plate.

• Pour the sample into the funnel until it is nearly full.

• Avoid shaking or compacting the material during loading.

4. Initiating Flow

• Remove the shutter quickly to allow the material to discharge freely.

• Do not tap, vibrate, or disturb the apparatus while the material flows.

• Allow the cup to fill completely until flow stops naturally.

5. Leveling the Cup

• Use a straight edge to strike off excess material flush with the rim.

• Maintain a smooth motion to avoid compressing the sample.

6. Weighing

• Weigh the filled cup to the nearest 0.01 g.

• Subtract the mass of the empty cup to obtain the net sample mass.

7. Calculation

Bulk density is calculated as:

Report values to three significant figures.

8. Repeatability

• Perform at least three measurements.

• The variation between results should not exceed ± 1 %.

Engineering Notes

• Method A is ideal for fine powders, micro‑granules, and free‑flowing resin materials.

• The QPI‑BDM1800A’s narrow orifice minimizes bridging and ensures consistent discharge.

• Cleaning the funnel and cup between tests prevents contamination and maintains accuracy.

• The stainless‑steel construction provides dimensional stability and long‑term durability.

Interpretation of Results

Bulk density measured by Method A reflects how a fine particulate material behaves under gravity without external compaction. It is commonly used for:

• Resin quality control

• Powder flow characterization

• Feed calibration for extrusion and molding

• Comparative evaluation of polymer blends and additives