Bulk Density Tester for Plastic Granules and Powders
塑料粒料与粉料堆积密度仪
- SKU DET-0004
- Density Testing
- CE (to be confirmed)
- ISO 9001 manufacturing (to be confirmed)
Price on request — FOB / CIF quoted per order
Prices depend on configuration, quantity and destination port.
Key specifications
| Cup volume | 100 mL standard |
|---|---|
| Funnel orifice | Per the applicable standard |
| Funnel angle | 45° (pourable materials) |
| Drop height | Fixed by the method |
| Measuring range | 0.1–1.5 g/cm³ |
| Balance resolution | 0.01 g |
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By Lab Manufacturers China Technical TeamLast reviewed Standards: ISO 1183-1, ISO 1183-2, ISO 1183-3
What is the Bulk Density Tester for Plastic Granules and Powders?
A bulk density tester measures the mass of granules, flakes or powder that fills a standard cup poured through a defined funnel. It characterises how a material behaves in feeding, conveying and storage, and is widely used for PVC resin and regrind.
What is the Bulk Density Tester for Plastic Granules and Powders?
A bulk density tester measures the mass of granules, flakes or powder that fills a standard cup poured through a defined funnel. It characterises how a material behaves in feeding, conveying and storage, and is widely used for PVC resin and regrind.
Overview
The apparatus consists of a funnel of defined angle and orifice, a stand, and a cylindrical cup of known volume, positioned so that material falls a fixed distance. The cup is filled without compacting, struck level with a straight edge and weighed, and the result is expressed as grams per millilitre or grams per cubic centimetre. A related parameter, the bulk factor, is the ratio of the apparent density of the moulded article to the apparent density of the material in the cup, and it indicates how much volume reduction occurs during processing. Because the funnel, orifice, drop height and cup size are all specified, the equipment must comply exactly with the method, and free-flowing material without lumps is required for a valid result.
How does it work?
The classical method applies Archimedes' principle: the sample is weighed in air and again while immersed in a liquid of known density, and the difference gives the sample volume. This suits void-free solid specimens and returns density to three or four decimal places. A density gradient column contains a liquid column whose density varies linearly with height, so a small specimen sinks to the level matching its own density and is read against calibrated glass floats, which is useful for very small or thin samples. Gas pycnometry measures the volume of a sample by helium displacement in a calibrated chamber, so it handles powders and porous or irregular material. Bulk and apparent density methods instead measure the mass that fills a defined volume, which is the relevant quantity for granules, powders and cellular plastics.
What are the key features?
- Funnel with specified angle and orifice
- Calibrated cup of defined volume
- Fixed drop height between funnel and cup
- Straight-edge levelling accessory
- Results in g/mL or g/cm³
- Bulk factor calculation support
What are the technical specifications?
A typical bulk density tester for plastic granules and powders configuration offers cup volume of 100 mL standard, funnel orifice of Per the applicable standard, funnel angle of 45° (pourable materials), drop height of Fixed by the method, measuring range of 0.1–1.5 g/cm³ and balance resolution of 0.01 g. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.
Which applications is it used for?
The Bulk Density Tester for Plastic Granules and Powders is used in PVC resin and compound bulk density checks, regrind and recycled flake characterisation, feeding and conveying behaviour assessment and storage volume estimation for granules. Across the wider Density Testing class, laboratories also deploy it for incoming verification of resin density, filler and mineral content estimation in compounds and crystallinity and formulation consistency checks.
Which standards and certifications apply?
Relevant standards and methods include ISO 1183-1, ISO 1183-2, ISO 1183-3, ASTM D792, ASTM D1895, ASTM D1622, ISO 845 and IEC 61010-1. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.
Temperature control is essential because liquid density and sample volume both change with temperature; record the temperature and apply the liquid's density-temperature table. Remove air bubbles from immersed specimens and from pycnometer chambers, as a single trapped bubble changes the volume materially. Weigh the specimen wet mass promptly to limit evaporation and use a covering liquid that does not swell or dissolve the polymer. Calibrate the balance and verify liquid density with a certified glass float or hydrometer at defined intervals. For bulk density, follow the specified funnel, orifice and cup, since changing any of these changes the result.
How do I select the right Bulk Density Tester for Plastic Granules and Powders?
Specify a bulk density tester when the material is handled as granules, flakes or powder and you need to know how much mass fits a given volume, for example in silo or feeder sizing and in PVC compound control. Confirm the funnel and orifice specified by the method you follow, because different standards define different geometries, and check that the cup volume matches the method's requirement.
How does it compare with other Density Testing variants?
Match the method to the material form. Solid, void-free mouldings and pellets are measured by immersion balances or by density gradient columns when only a small specimen is available. Powders, porous parts and materials that must not contact a liquid are measured by gas pycnometry. Granules, flakes and powders that are handled in bulk are characterised by bulk or apparent density, and rigid cellular plastics by their own apparent density method with a defined specimen. For specification testing, follow the method named in the material standard: ISO 1183 parts and ASTM D792 give different procedures and tolerances for solid plastics, and results from different methods should not be mixed in one data set.
Full specifications
| Cup volume | 100 mL standard |
|---|---|
| Funnel orifice | Per the applicable standard |
| Funnel angle | 45° (pourable materials) |
| Drop height | Fixed by the method |
| Measuring range | 0.1–1.5 g/cm³ |
| Balance resolution | 0.01 g |
| Sample mass per test | 100–500 g |
| Repeatability | Within 2% for free-flowing granules |
| Materials | Stainless steel cup and funnel |
Indicative values for this product class. Final specifications are confirmed on the quotation and in the calibration documents supplied with the instrument.
Applications
- PVC resin and compound bulk density checks
- Regrind and recycled flake characterisation
- Feeding and conveying behaviour assessment
- Storage volume estimation for granules
Key features
- Funnel with specified angle and orifice
- Calibrated cup of defined volume
- Fixed drop height between funnel and cup
- Straight-edge levelling accessory
- Results in g/mL or g/cm³
- Bulk factor calculation support
Frequently asked questions about Bulk Density Tester for Plastic Granules and Powders
PVC dry blends with higher bulk density feed more mass per screw revolution, so output, residence time and heat history change. It is also a fast indicator of formulation and of dry-blend quality, since an under-fused or poorly mixed blend usually shows a different bulk density from an acceptable one.
Both describe the mass of material filling a volume, but the terms belong to different materials and methods. Bulk density is commonly used for granules and powders poured through a funnel, while apparent density is the term used for rigid cellular plastics measured on a defined specimen by a geometric method. Always report the method used.
Use dry, lump-free material, keep the drop height and pouring method identical, avoid vibration during filling and level the cup with a single straight-edge stroke. Sieving out fines or agglomerates before testing, and taking the average of at least three fillings, usually brings repeatability within a couple of percent.
A density gradient column can measure fragments of a few milligrams, because the specimen simply settles at the level matching its density. The immersion method also works if the fragment is large enough to weigh accurately in air and in liquid without significant surface tension error, but very small specimens make both weighings uncertain.
Polymer matrices have densities around 0.90 to 1.20 g/cm³, while mineral fillers are typically 2.6 to 2.8 g/cm³ and glass fibre about 2.5 g/cm³. The measured compound density therefore rises with filler fraction, so a density check detects a loading error quickly, although exact quantification requires ashing or thermogravimetry.
Bulk density is the mass of granules or powder that fills a defined volume, so it includes the voids between particles and depends on particle shape, size distribution and how the container was filled. True density measures only the material itself and is always higher. Both values are reported for powders and granules.
