CT 227 - Cleanness Value

Question 1

Step 1: What is done first?

Answer 1

Split or quarter material down to mass specified by its nominal size. 1x4 is 2500g ± 125g

Question 2

Step 2: What is done 2nd?

Answer 2

Dry to constant mass at 230° F ± 9° F

Question 3

Step 3

Answer 3

Cool to room temp.

Question 4

Step 4

Answer 4

Place specimen in wash vessel, add appropriate amount of water, and clamp the lid.

Question 5

How much water is added to 1x4 or less?

Answer 5

1000mL ± 5 mL

Question 6

How long after adding the water should you start shaking the specimen?

Answer 6

1 min ± 10 sec

Question 7

How long should the sample be agitated for 1” x No.4?

Answer 7

2 min ± 5 sec

Question 8

How many times do you swirl the specimen in the wash vessel?

Answer 8

5 or 6 times

Question 9

What sieves are used to pour specimen into after agitation?

Answer 9

No. 8 and No. 200

Question 10

What is done to clean the wash vessel?

Answer 10

Small amount of fresh is sprayed into to clean.

Question 11

What do you do with material caught on No. 8 sieve?

Answer 11

Discard

Question 12

What do you do to clean concentration of material on No. 200 sieve?

Answer 12

Re-rinse concentration by pouring the wash water through the sieve again as many times until all material smaller than No. 200 has passed.

Question 13

What is done to material caught on No. 200 sieve?

Answer 13

Discard

Question 14

How should you adjust the volume of wash water?

Answer 14

Pour all water into graduated cylinder and add fresh water to get back to original amount of water that you started with, 1000mL.

Question 15

What level is the smaller graduated cylinder filled to?

Answer 15

0.3 in.

Question 16

How is the small graduated cylinder filled?

Answer 16

Stir wash water vigorously with one hand until all fines are in suspension. Use circular motion allowing fingers to rub the sides and bottom of the collection pot. Get all particles into suspension.

Question 17

How high do you fill the small graduated cylinder to?

Answer 17

15 in. mark

Question 18

How is the graduated cylinder mixed?

Answer 18

Plug the cylinder and thoroughly mix the wash water by inverting 20 times in 35 seconds. Allow the air bubble to traverse the length of the cylinder.

Question 19

How long does the graduated cylinder sit for?

Answer 19

20 min ± 15 sec.

Question 20

After 20 min period what is the sediment read to?

Answer 20

Nearest 0.1 mark.

Question 21

What formula is used for converting height to Cleanness Value?

Answer 21

CV= (3.214-0.214H)/(3.214+0.786H) x 100

Question 22

What is the rounding of the Cleanness Value?

Answer 22

Round to the nearest whole number.