PORCUPINE OPENER | Working Principle

OBJECT : To open and clean the cotton.

Type : Semi fast controlled feeding bladed beater.

The cotton fed by the previous opener is carried forward by the feed lattice. The sheet of cotton now pass between pedal and pedal roller. The weight of cotton fed per unit time is maintained constant by this pedal feed regulating motion.clip_image001

Pedal roller feed the sheet of cotton in between pair of feed roller which is weighted to give necessary grip on the cotton. 16 circular disc are mounted on the shaft of this opener. 14 to 18 striker blades are rivitted alternatively on each circular disc. Each striker is bent to a slightly different angle.

The compressed sheet of cotton delivered from the feed roller is heavily beated by the rapidly revolving striker of the porcupine beater against grid bar.

Because of this beating action, the cotton is effectively opened and extracted trash particles are passed through the spacing of the grid bar.

At the end of the grid bar, stripping rail is provided, this is a metal bar which is set about 1/16 inch away from the end of the striker. This small clearance between stripping rail and striker prevents bunches of cotton being carried around by the beater.


cotton from the beater region is taken out by the air current set by the fan and is deposited on to the cages.

During the passage of cotton between beater section and cage, it passes over a series of suspended leaf bars where lighter impurities are removed. The compressed sheet of cotton is delivered from the cage by means of pair of delivery roller to the next process. While processing fine cotton and viscose rayon, porcupine opener is not recommended, in this case this opener is by passed by suitable by-pass arrangement provision in this opener.

Setting particulars :

Slightly wider setting is generally used for medium long stapled cotton to avoid fibre damage.

Also wider setting is recommended when a very heavy feed is used, so as not to crush the fibres.

Setting between beater and feed roller = 3/16 inch Setting between beater and first gridbar=3/16 inch Setting between beater and last gridbar = 7/16 inch Setting between beater and stripping rail.=1/16 inch;

Inclination of the grid bars are so arranged that the resistance to the movement of cotton gradual1y decreases, from feeding end to the delivery end.

Setting between grid bar and beater will be gradual1y increased from first grid bar to the last grid in gradual stages.

Wider setting between stripping rail and beater causes unnecessary reprocessing of fibre in the beater section, because of this over treated cotton or repeatedly beated cotton, curely cotton is produced.

Pneumatic Conveyor

Air current setup by the fan with condenser in the blow room line suck the cotton tufts from one machine and transfer or convey to another through pneumatic conveyor and is fed to the next machine by condenser.

Long , curved and 'U-bend' in conveyor pipe line is one of the cause for nep formation in Blow Room.