Humboldt H-1449 User Manual

H-1449_man_10.09

product manual

H-1449

Vacuum Extractor

1. Scope

This is to determine bitumen content of hot paving mixtures by use of the vacuum
extractor. The aggregate remaining after extraction of the bitumen may be used for sieve
analysis. This test is designed for field control work on freshly mixed hot paving mixtures,
but may be adapted for other uses.

2. Apparatus

Vacuum extractor complete with vacuum pump, gasket, rubber tubing, filter paper,
support plate and funnel ring, similar to that shown in Fig 1. The vacuum extractor is
currently available in two sizes, (1) 12" filtering surface using 33 cm. diameter filters
and (2) 10" diameter filter surface using 29 cm. filters. The larger extractor has a test
specimen capacity of 2000 to 3000 grams, the smaller extractor has a test specimen
capacity of 1400 to 1900 grams.

2.1 Filter paper, medium grade, fast filtering of the diameter required to fit the
extractor.

2.2 Gas hot plate 3-burner with steel plate cover and thin pad.

2.3 Metal beaker, stainless steel, and nine-quart capacity.

2.4 Two (2) 4000 ml glass Erlenmeyer flasks.

2.5 Glass graduated 500 ml capacity.

2.6 Plastic wash bottle 500 ml capacity, filled with methylene chloride.

2.7 Dial thermometer 50°F to 180°F.

2.8 White enameled drying pan 9" x 16" x 2 ½".

2.9 Mixing spoon 12" long.

2.10 Spatula 9" long.

2.11 Torsion balance 4000 gm capacity and set of weights.

2.12 Stiff bristled brush, 1" wide.

2.13 Diatomaceous silca filtering aid conforming to ASTM D604, Type A (Celite)

Note 1: Use apparatus listed under 2(N), (O), (P), and (Q), only with hard to filter
mixes as in method B.

2.14 1000 ml. Erlenmeyer flask.

2.15 4" diameter watch glass.

2.16 Metal tongs, 6" to 8" long.

Reagents:

2.17 Denatured ethyl alcohol (alcohol)

2.18 Methylene chloride

3. Sample Preparation

The test specimen shall be that obtained by a tube sampler and not further reduced
in size, or be the end result of splitting or quartering of a large sample conforming
to AASHTO T168. The size of the test specimen shall be governed by the nominal
maximum size of particle of mineral aggregate in the mixture. The approximate minimum
size of test specimen shall conform to the requirements shown in Table 1. Introduce
the specimen into the tare metal beaker and weigh to the nearest 0.1 gm. If specimen
temperature at this point is above 130°F, it should be allowed to cool to a temperature

of less than that, then pour 200 ml of alcohol on to the specimen. Add approximately
700 ml of methylene chloride, stir occasionally for approximately five minutes or until all
asphalt is visually in solution.

TABLE 1: SIZE OF TEST SPECIMEN

NOMINAL MAXIMUM

SIEVE SIZE

No. 4 500

3/8" 1000

½" 1500
¾" 2000

1" 3000

1½" 4000

APPROXIMATE MINIMUM

WEIGHT OF SPECIMEN (GM)

4. Method A

PROCEDURE

4.1 Place a dry tare filter on the vacuum extractor and tighten the wing nuts finger tight.
(care must be taken to see that the filter is centered.)

4.2 Start the vacuum pump and decant the solvent from the prepared specimen into
the extractor then gently pour the specimen into the vacuum extractor, being sure
to wash the beaker completely clean with the wash bottle. Gently distribute the
specimen evenly over the filter paper with spatula.

4.3 When the solvent added under section 4.2 has been vacuumed off, turn off the
vacuum pump and open the vacuum valve, then pour enough methylene chloride,
approximately 700 ml, to cover the specimen stir gently with spatula until all
aggregate has been moved slightly then vacuum off the solvent. This procedure is
repeated until the solvent in the inspection tube is a light straw color. (Note: solvent
may be slowed for observation by partially opening vacuum valve and reducing
vacuum to a few inches.)

4.4 Let the vacuum pump run for a few minutes after the last wash, to aid in drying
the specimen. Scrape the aggregate away from the side of the funnel ring toward
the center of the filter to avoid loss when the ring is removed. Remove the ring
and brush the clinging aggregate into the drying pan. Then pick up the filter
paper and aggregate by holding the filter paper on opposite sides and raising it
straight up. Place the specimen in the tare pan and brush the clinging aggregate
from the filter into the pan. The aggregate shall then be dried on the hot plate,
bringing it to a temperature of about 130°F in ten minutes. Stir occasionally. DO
NOT LET SPECIMEN REACH OVER 140°F. When visually dry, sniff cautiously for
odor, continue drying and stirring until odor free. Weigh filter and aggregate in pan
and record. Let stand five minutes and weigh again. If weight loss is less than 0.01
percent of the specimen weight, the aggregate shall be considered dry. If not dry let
stand, stirring occasionally until weight loss is less than 0.01 percent in five minutes.
Then weigh and record. Subtract the weight of the filter and pan to determine the
weight of the extracted aggregate.

CALCULATIONS

Calculate the percentage of bitumen extracted as follows:

Bitumen extracted, percent of gross test specimen weight

Where:

S= Weight of test specimen
A= Weight of extracted mineral aggregate

Add the retention factor (note 2), previously determined for the job mix, to the percent
bitumen extracted and report total as percentage of bitumen in the mix (note 3).

Note 2: see section 8 for procedure for determining the retention factor.
Note 3: procedure as detailed in section 4.4 does not require a moisture correction. If

the moisture in the bituminous mixture being tested is over 0.6 percent, then routinely,
the amount of moisture shall be determined by standard test procedures. In this case the
extracted aggregate shall be dried to a constant weight at 230°F, ± 9.

The percentage of bitumen extracted shall be calculated as follows:

Bitumen Extracted, percent of dry mixture

Where:

S= Weight of test specimen
A= Weight of extracted mineral Aggregate,
W= Weight of water in specimen

Add the retention factor to the percent bitumen extracted and report as the percentage
of bitumen in the dry mix.

5. Retention Factor

SCOPE

Certain types of aggregate will retain a small amount of bitumen after being tested by
the vacuum extractor; this should be taken into consideration in calculating the final
percent bitumen in the mix. The following procedure is used to determine the retention
factor.

Note 4: where the retention factor is known to be 0.04 or less it may be disregarded.

PROCEDURE

5.1 The test procedure as outlined in the following paragraphs shall be performed
separately on at least two specimens of aggregate representative of the material to
be used in the mix. Test specimen size shall conform to the requirements of Table 1.
The aggregate specimen shall be dried to a constant weight at 275°F, plus or minus
five.

5.2 Place specimen in a tare metal beaker and weigh to the nearest 0.1 gm.

5.3 Immediately add asphalt cement of the amount and type called for by the job mix
formula. The asphalt cement shall be preheated to 300°F to 350°F. Calculate the
exact percentage of bitumen added to the nearest 0.01 percent.

5.4 Mix the bitumen and aggregate by hand until aggregate is thoroughly coated. The
mix specimen shall be kept within the specified job- mix temperature range by
placing it on the hot plate during mixing. The mixing tool shall remain in the beaker
until the specimen is ready to be transferred to the extractor.

5.5 Allow the specimen to cool to less than 130°F. Then add alcohol and methylene
chloride and stir as in section 3.

5.6 Proceed as in section 4, procedure method A, except that the aggregate shall be
dried back to a constant weight at 275°F, ± 5.

CALCULATIONS

Calculate the percentage of bitumen extracted and the retention factor as follows:

R= P1 - P2

Where:

S= Original weight of mix specimen (dry aggregate plus bitumen added)
A= Weight of extracted mineral aggregate
P1= Percent bitumen added to the mix
P2= Percent bitumen extracted from the mix
R= Retention factor

If there is more than 0.05 percentage points between the two tests, run a third test and
average any within 0.05 of each other.

6. Method B

SCOPE

6.1 This method is to be used on mixes such as those containing hydrated limes that are
very slow filtering.

6.2 Preparation of sample shall be as given in section 3.

6.3 Place a dry tare filter on the vacuum extractor and tighten the wing nuts finger tight.

6.4 Weigh 50 gm of oven-dry celite into a 1000 ml Erlenmeyer flask and add 500 ml of
methylene chloride. Swirl until celite is completely in suspension.

6.5 Immediately pour celite and methylene chloride onto filter, turn on vacuum pump
and let run until pad formed by celite is surface dry and begins to crack slightly.

6.6 Place watch glass in extractor and gently pour solvent onto it; remove it with tongs
and wash with wash bottle, then add the rest of the sample and proceed as in
section 4.2, 4.3 & 4.4 under procedure method A, except in order to find the dry
weight of the Aggregate, subtract the weight of the filter, pan, and the celite from
the total weight.

7. Sieve Analysis (Procedure)

Use the standard method of test for mechanical analysis of extracted aggregate,
AASHTO T30. If celite is used as in method B, no correction need be made as celite is all
minus No. 200 mesh and will be lost in the wash process.

H-1449.5

H-1449.1

H-1497.613, 1 PKG.

H-1448SP

H-1448.1

H-1449.4

H-1449.2

H-1449.3

H-1449.6

H-1448RT
3 FEET, (REF.)

Figure 2: H-1449 parts

H-1448 and H-1449 Extractor Replacement Parts

Description Model

Fluorosilicone o-ring H-1448.1
Gauge, H-1448 H-1448G
Glass Tubing, includes 2 o-rings H-1448GT
Free-flow vacuum plate H-1448GS
Stainless Steel Plate, as provided H-1448P
Stainless Steel Plate, Heavy-Duty H-1448HP
Rubber Tubing H-1448RT
Clear, Heavy-wall, Vacuum Tubing H-1446

4,000cc Erlenmeyer Flask, meets ASTM
D2172 and AASHTO T164 (Method E)

8" Sieve adapter H-1447

H-4913.4M

Warranty

Humboldt Mfg. Co. warrants its products to be free from defects in material or
workmanship. The exclusive remedy for this warranty is Humboldt Mfg. Co., factory
replacement of any part or parts of such product, for the warranty of this product please
refer to Humboldt Mfg. Co. catalog on Terms and Conditions of Sale. The purchaser is
responsible for the transportation charges. Humboldt Mfg. Co. shall not be responsible
under this warranty if the goods have been improperly maintained, installed, operated
or the goods have been altered or modified so as to adversely affect the operation, use
performance or durability or so as to change their intended use. The Humboldt Mfg. Co.
liability under the warranty contained in this clause is limited to the repair or replacement
of defective goods and making good, defective workmanship.

Humboldt Mfg. Co.

875 Tollgate Road
Elgin, Illinois 60123 U.S.A.

U.S.A. Toll Free: 1.800.544.7220

Voice: 1.708.456.6300

Fax: [phone]

Email: [e-mail]