1

2

Hazbi elahi23152

3

Cropping/shearing

4

Cropping Shearing is the process of cutting protrouding fibers and yarns to give smooth and clean appearance by rising knives and blades

Definition:

5

1.To remove the protruding yarns and filament from the surface of the fabric.2.To give clean and smooth appearance to the fabric.3.To control pill formationWool fiber are preferred for this process

Objectives:

6

• History of shearing and cropping is marked from 15 century.• At that time at was done manually by manual tool called shears.

History :

7

Why we preferred cropping instead of singeing here:

Singeing is widely used to remove protruding fibers . Shearing is preferred not only for wool, all protein fibers undergo this process due to below reason. i. Convolute is formed on there tips.. ii. Convolute gives harsh feel.. iii. It also variate in shade.

8

There are several helical blade are arranged in a series fabric pass these blades.Direction of blade motion is opposite to the direction of fabric motion,There is an other vertical blade called ledger, place beneath the fabric which shear the other side.

How it work:

9

10

11

• It increases flame retardency of fabric small fiber at surface of fabric attract fire easily• Increase aesthetic properties like smoothness , luster etc.… • in cropping process no threat of fabric destruction present on occasion of power shut

downer machine stoppage.• It is cheaper and simple.• It can also produce even hairy effect which can not be produced in singeing machine.

Advantages

12

1. It is comparatively slow and inefficient machine.2. Multiple treatment is required if finer results needed.

3. Service is required after every process.4. For controlled removal of hair slow cropping is required.

Dis advantages

13

• Crop Cum Cobbler shear

• These machines are manufactured to cut various sizes of Blooms and Slabs. The capacity of these machines varies from 50mm to 200mm for Blooms & 50mm x 200mm to 125mm x 400mm for Slabs. Six (6) numbers of gears are provided to facilitate operations with small power. The body is made from M.S. (Plates) instead of cast iron to cover the risk of any breakage.

Machinery

14

• Scrap Shearing Machine:

Shearing machine is capable of shearing thick and thin sheets without any distortion and is provided with a replaceable hardened liner to ensure minimum wear. The most important feature of these machines is that they are designed for cutting metals in a very short amount of time. These machines are made up of steel which makes them hard and strong. The plate or scraps sharing machines are highly demanded in the market and are available in different capacities.

15

16