Qualitative wet-strengthened filter paper grades are manufactured for applications using in a system or apparatus that operates under pressure or vacuum conditions. They contain a small amount of chemically stable, insoluble binding resin which strengthens the natural fiber-to-fiber bonds under wet conditions.
- Quantitative analysis
- Consistent performance
- High wet-strength
- Hardened grades available
- Custom cut
Mining Laboratory Applications:
ASTM D4371-06 Determining the Washability Characteristics of Coal (Float/Sink)
The effectiveness of chemical treatment used to float particulate waste in treatment facilities often requires this test evaluation. The filter paper must have sufficient throughput so that the drainage rate is not adversely affected. Grade 615 is commonly used in this application.
Construction Laboratory Applications:
ASTM D1561-92 Preparation of Bituminous Mixture Test Specimens by Means of California Kneading Compactor
A mechanical compactor consolidates test specimens to replicate the equipment being used for the compaction of asphalt concrete pavement. Grade 613 or Grade 615 is installed between the asphalt mixture and the mold to prevent sticking during the compaction process.
ASTM D1883-07 CBR (California Bearing Ratio) of Laboratory-Compacted Soils
Laboratory compacted samples of pavement subgrade, subbase, and base/course materials are tested for California Bearing Ratio, which defines the strength of cohesive materials. Grade 615 is used as a spacer disc to prevent the samples from sticking to the test equipment.
ASTM D-2172-11 Quantitative Extraction of Bitumen from Bituminous Paving Mixtures
This procedure has five, A-E, methods in which to evaluate bitumen content. Method A is done using a centrifuge extractor. A filter paper disc, placed in the centrifuge, is used to collect the extract from the sample. The filter disc is then tested. Grade 901 meets the requirements for the filter rings. Method B is done using a reflux extractor. The reflux extractor consists of two cone type screens. The filter paper used with this extraction method is Grade 615. Method E utilizes a vacuum extractor. This test requires a medium grade fast filtering qualitative filter. Grade 615 is ideal for this procedure. Methods C and D do not use paper.
ASTM D2844-07 Resistance R-Value and Expansion Pressure of Compacted Soils
This information is gathered to predict the R-value and Expansion pressure of soil that would be subjected to road traffic. The test is done with a stabilometer and expansion pressure device. This test needs absorptive pads between the sample and the mold to prevent sticking. The method calls for a creped filter, Grade 615 and a smooth filter, Grade 613.