the names and their roles of primary sizing ingredients are given below:
this is untreated starch powder. Mainly maize starch, sago starch, wheat starch, potato starch are used as adhesive agent in sizing. The viscosity of sizing liquor with untreated starch is always high. It gives poor penetration in the warp yarn. This starch is suitable for sizing of coarse count of yarn up to 20s count.
it is chemically treated starch. It has lower viscosity than untreated starch. It easily penetrates in the yarn. When warp count increases, the size pick-up percentage is also increased thus concentration of liquor is also increases but viscosity of liquor is kept almost same by using thin boiling starch. It may be successfully used in the sizing of medium count of warp yarn. It is little expensive than untreated starch.
it chemically modified starch. It has very low viscosity. It gives the best penetration effect in the yarn. It is suitable for all types yarn count. It can be used for sizing of warp of high speed loom. Good quality of fabric results with this adhesive. Maximum efficiency can be achieved by using this adhesive. This is much expensive so that it is used in the sizing of fine count of warp yarn only.
The secondary sizing ingredients of sizing agents are given below:
A braking system is attached with each pair of roller. Beam tension is adjusted by loosening or tightening the hand wheel. The alignment of beam is also done by help of this hand wheel. The yarn guiding rollers are fitted in the creel which guide the warp of each beam. Zigzag or vertical creel is used in the sizing machine. Zigzag creel occupies more space than vertical creel.
the sow box has a stainless steel tub. The sizing liquor is filled in this tub.
it is mounted just before the immersion rollers, it guides the warp sheet during process.
the warp sheet passes under the immersion rollers. Two pairs of immersion rollers are used in a sow box, immersion rollers helps to immerse the warp sheet into the sizing liquor. The warp sheet first passes under one pair of immersion rollers then between nip of stainless steel and squeezing rollers. Now warp sheet again passes under other pair of immersion roller and finally warp sheet passes between nip of other stainless steel and squeezing rollers.
When the warp immerses into the sizing liquor, it has excess amount of sizing liquor with it. There is need to eliminate this excess amount of sizing liquor from warp. The warp coming out of immersion rollers passes between the nips of squeezing roller, which is mounted just over the stainless steel roller. Two squeezing rollers are used in a sow box. The squeezing roller applies the pressure on the warp sheet and eliminates excess amount of sizing liquor from it.
This is mounted in the circulation box of tub. It is perforated and connected to the steam line. Main function of this perforated steam pipe is to maintain the temperature of sizing liquor in the sow box. A steam valve is fitted in the steam line which regulates the temperature of sow box.
The pneumatic cylinders are fitted at the both ends of squeezing rollers. These cylinders perform up and down movement of squeezing rollers. The squeezing pressure is maintained by these cylinder. The compressed air is supplied continuously to these pneumatic cylinders.
A pressure gauge is fitted between the pneumatic cylinders and air supply line. This pressure gauge reads the pressure during process.
An air pressure regulator is used to control the squeezing pressure. By rotating the air regulator valve the squeezing can be increased or decreased according to requirement.
The temperature sensor is immersed in the sizing liquor. This sensor senses the liquor temperature and sends the signal to the control panel.
The circulation system mainly consists of a geared feeding pump. When the tub of sow box is filled with sizing liquor, it begins to fall into circulation box. The liquor from here passes into the inlet of feeding pump. The outlet of pump is connected to a sow box. The feeding pump continuously circulates the sizing liquor.
some drying cylinders are driven negatively. These cylinders are revolved due to warp tension over the cylinder. The last three or four cylinders are driven positively. A steam trip is mounted on each cylinder which releases excess amount of steam pressure. The steam valve fitted with each cylinder regulates steam pressure in the cylinder. The temperature sensors fitted with each cylinder reads the temperature of cylinder and sends the signal to the control panel.
comes out from drying unit, the ends are sticked to each other. The yarn separators are inserted into the warp sheet in definite sequence. The number of yarn separators depend upon the number of warper’s beams to be used. The number of yarn separators is always one short of number of warper’s beams. The yarn separators are fixed on their brackets. The warp sheet moves toward the head stock of machine. This movement of warp sheet helps to separates the ends from each other.
The warp sheet again passes over another pressure roller. The pressure of these rollers are controlled by pneumatic cylinders. These cylinders also help to lift upward the pressure rollers. A metallic cover is mounted over the drag rollers which prevents to fall any foreign material between the pressure roller and drag roller. A protection grid is mounted just front of drag roller which protect the operator’s hand.
A hand wheel is used to reduce or increase the reed width. Width can be adjusruted by rotating hand wheel in clockwise or anticlockwise direction. There is another mechanism attached with this reed which helps to move it left and right direction.
The one flanged toothed pulleys connected to gear transmission system and other end is connected through a chain sprocket to the receiving device. When the diameter of driver pulleys is increased, the diameter of driven pulleys reduce simultaneously. Therefore the speed of the motion receiving device is increased. When the diameter of driver is reduced, the speed of motion receiving device is decreased. The diameter adjustment is achieved by rotating hand wheel.
A steam is used to maintain the temperature in the vessel. A temperature meter and pressure gauge are fitted in in this cooking vessel to reed temperature and cooking pressure. Normally the volume of cooking vessel is 1000 litres. One inch height of cooking vessel contains 20 litres of volume of liquor.