The checking of sieve which is used in fineness test is a very easy method. In this post you will find out details about that how to check the sieve for fineness test of cement.

How to Check the Sieve for Fineness Test of Cement

Table of contents  (toc)

First we know that why we need to check the sieve.

   The sieve is checked to correct the fineness value of cement. After using the sieve many times, some errors come in it. To rectify this defect, the sieve is checked with a standard sample.

The sieve is checked after every 100 sieving.

Apparatus and Materials Used for Checking Sieve

1. 90 μm Indian Standard Sieves with pan as per IS: 460 (Part 1 and 3): 1985
2. Weighing balance capable of weighing up to 10 g to the nearest 0.01 g
3. A nylon or pure bristle brush, preferably with 25 mm to 40 mm bristle, for cleaning the sieves
4. A tray fitting beneath the sieve frame to avoid loss of material during sieving
5. A sieve lid fitting above the sieve frame to avoid loss of material during sieving
6. Gauging trowel
7. Tamping rod
8. Sieve Shaking Machine (optional)
9. Standard reference sample of known sieve residue

IS Code Used for Checking Sieve

IS 4031 (Part-1) 1996

Procedure for Checking Sieve 

1. Agitate the sample of cement to be tested by shaking for 2 min in a stoppered jar to disperse agglomerates.
2. Wait for two 2 minutes.
3. Stir the resulting powder gently using a clean dry rod in order to distribute the fines throughout the cement.
4. Fit the tray under the sieve.
5. Weigh approximately 10 g of the reference material to the nearest 0.01 g and place it in the sieve, being careful to avoid loss. (Weight of sample; W₁)
6. Rub the cement particle well with your fingers so that no air set lumps are left and agglomerates are dispersed.
7. Fit the lid over the sieve.
8. If you have a sieving machine then you just need to put the sieve in the sieving machine and start the machine for 15 minutes.
9. If you don’t have the sieving machine then no problem, you can shake it also with your hands. 
10. Hold the sieve with pan in both hands and sieve with gentle wrist motion, in circular and vertical motion for a period of 15 minutes without any spilling of cement until no more fine material passes through it.
11. Place the cover on the sieve and remove the pan.
12. Now tap the other side of the sieve with the handle of brush and clean the outer side of the sieve.
13. Now weigh the retained amount of cement on the sieve. (Weight of cement sample left on the sieve; W₂)
14. Calculate the fineness of cement (P₁) by formula W₂/W₁×100 % to the nearest 0.1 percent.
15. Empty the pan and fix it below the sieve.
16. Then repeat the whole procedure again using a fresh 10 g sample of cement and calculate the fineness of cement (P₂) to the nearest 0.1 percent.
17. The two values of P₁ and P₂ for a satisfactory sieve should differ by not more than 0.3 percent. Their mean P = (P₁ + P₂)/2 characterizes the state of the sieve.

Calculation

● Let the given known residue percentage on the 90 μm mesh of the standard reference material is R₀.

● Now calculate R₀/P to the nearest 0.01. This is called sieve factor and denoted as F. F may have a value of 1.00 ± 0.20.

● If the residue percentage of fineness test of cement by sieve analysis is R, determined as IS 4031 (Part-1) 1996, then correct it by multiplying by F.

● The value of M×F gives the most corrected result of fineness value of cement.

FAQs

Why we need to check sieve?

The sieve is checked to correct the fineness value of cement. After using the sieve many times, some errors come in it. To rectify this defect, the sieve is checked.

After how many sieving we need to check the sieve?

The sieve should be checked after every 100 sievings.

Is there any other method to check the sieve?

Yes, there is another checking procedure of sieve which is called optical method and it is described in IS 460 (Part 3): 1985.

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Fineness test of cement by sieve analysis