Table B4. Pressure losses and air flows through DustControl 2700 vacuum cleaner: 09/13/2007 Round 2

Before (B) or after (A) adding 5 pounds

Total weight added to vacuum cleaner (lb)

Venturi meter δP (inches of water)

Static Pressure Measurements with manometer (inches of water)¹

Absolute pressures measured with pressure transducers.(psi)

Time to start loading

Time to stop loading

Filter pressure loss inches of water, corrected for calibration curve of the pressure transducers

Air flow from venturi meter (cfm)

Upstream "before cyclone"

Downstream "after cyclone"

δP

Upstream of final filter (55481)

Downstream of filter at inlet to vacuum cleaner motor (53478)

B

5

7.3

-4

-8

4

13.824

13.147

12:53 pm

12:56pm

19.23

71.12

A

7.2

-3.8

-5.8

2

13.899

13.13

21.77

70.63

B

5

7.7

-4.4

-6.9

2.5

13.874

13.197

1:00pm

1:02pm

19.22

73.02

A

7.7

-4.2

-6.2

2

13.891

13.13

21.55

73.02

B

5

8.8

-4.4

-6.2

1.8

13.874

13.18

1:15pm

1:17pm

19.69

77.99

A

7.7

-4.1

-6.3

2.2

13.891

13.08

22.93

73.02

B

5

8.9

-3.9

-6.2

2.3

13.874

13.13

1:26pm

1:27pm

21.08

78.43

A

8

-4.1

-6.3

2.2

13.883

13.088

22.49

74.41

B

5

7.7

-4.3

-10

5.7

13.84

13.088

2:00pm

2:02pm

21.30

73.02

A

7.4

-4.1

-6.1

2

13.857

13.071

22.24

71.60

B

5.2

8.9

-5.1

-7.1

2

13.849

13.172

2:08pm

2:10pm

19.23

78.43

A

8.4

-4.4

-7

2.6

13.857

13.088

21.77

76.22

B

5

8.2

-4.5

-6.6

2.1

13.849

13.205

2:16pm

2:18pm

18.31

75.32

A

8

-4.5

-6.4

1.9

13.866

13.055

22.93

74.41

Final

8.7

-4.6

-6.7

2.1

13.832

13.238

2:22pm

16.93

77.55

¹ Static pressure is the difference in pressure from atmospheric pressure. Negative static pressure indicates that pressure is less than atmospheric pressure.