What is a textile slitter operator?

Answer 1

a slitter operator runs a machine that slits fabrics. A roll usually 70 in in length of fabric and maybe around 300-1200 yards is loaded onto the back of the machine. Fabric is tied off and ran through the machine around rollers, under platform, through knife setup, around and through pinch rollers in the front. Machine is set to a particular cut size with the amount of rolls, length, and heat expansion factored in. Machine is then set to a low speed to roll as it heats up. Machine is heated between 680 and 720 degrees depending on process control. If the machine heats up without being in motion, the heat bar will warp. Once machine is up to temp, now we set the beds. Beds are lined up with knives. If beds are set before machine heats up to temp, they will all have to be reset due to heat expansion. Once beds are set, we will clean all carbon off of our knives. Now, we set all controls to what developed process calls for. Usually with peel ply Ill set my top and bottom clutch (front rollers) to 20. ill set my brake at around 30+ depending on weight of roll, amount of yards, and roll's core fit (loose or tight) on brake arm. Brake should be decreased throughout. too much brake and it will pull causing stress on clutches. Not enough brake and the clutches will pull the roll too fast and you will end up with a burnout/floppy selvage/creases/shifts/telescoping. Now we will make a test cut with all the beds set, machine heated, low brake... before we do the test cut, we load up the correct amount of cuts worth of cores staggered between top and bottom clutch with two extra for the selvage (unless you have an air suction system which is great until you lose air and then you have a major burnout and loose reels, have to drop beds, or doff early... Now that he clutches are set with cores. an experienced operator would usually already have cheat marks on the air shaft for core line up. But since we are inexperienced, lets waste some fabrics and make some cuts to line up our cores... Set brake to around 15-20... raise pinch roller...set edge eye..run fabric through machine enough for edge eye to straighten roll. YPM should be set to above 25 as to not carbon up your knives.. raise the bed bar to the knives and run the cuts up through to the front. Stop First! drop bed bar. Run to front of machine...tape across the cuts to keep them together and perfectly lined up... now adjust your cores to line up with your cuts and selvage. Once you have a line up..Shoot some air in the shafts... throw some two sided tape across both top and bottom clutches over cores all the way across in one swipe for each clutch... wrap cuts over the two sided tape and press.... cut away the waste, make your cheat marks on the left hand side of each core on the shaft with a dry erase marker. NOW raise those beds and start it up.... HELPFUL INFO: spatulas, scissors, screw drivers, collar tighteners, and heat resistant gloves are your best friends......

this walkthrough is only for a performance 3in dual shaft slitter.... Cutdown, Inkers, and wide impression slitters are different but run on the same basic ideas.

You may have knives of different sizes which of course would have to be calculated by your Setup technician. Some have 1 1/4 in shafts.... Cutdown slitters usually have smaller knives .125 and slit smaller rolls that were preslit on a wide roll slitter. Wide slitters have larger knives.. usually .250 per knife

to calculate you setup, you need to calculate heat expansion... On your basic 70 in setup on 2 1/2 in calrod. if you are setting up for 3in cuts....depending on the variance you are allowed, to get closest to 3in we will use....

A. .250 knife

B. combination of spacers

C. .250 knife

heat expansion would be 3.000 times 1.006 minus 3.000 which should equal .018 which needs to be calculated into your spacer setup depending on what variance you are allowed to have..... I was setting up and operating with a 1/32 of an in max and 1/64 of an inch target... spent many days looking through an optical comparator during process creation..... good luck... find another job