How to Install and Adjust the Slitter Knives?

PUBLISH DATE：2023-05-08

Plenty of fabric, paper, and film items are in direct contact with the slitting machine, in which slitting knives play a pivotal role. Incorrect usage or installation of the slitter knives can easily decrease the lifetime of the slitting knife.
The poor installation also leads to a big percentage of cutting powder, and the cutting tools won't satisfy the conditions for the slitting index.
So, it is important to ask how to install and adjust the slitter knives. This article aims to answer this important question. Let's get started.

Install the Slitter Knives

From the top dish slitter knives, wipe off the rust-resistant oil. Next, position it on the bottom knife and put the upper knife's slot at the thimble of the bottom knife from the unobstructed place upward.
Afterward, utilize the spacer of the slitting knife and attach the upper knife. Plus, you can employ a few tools to keep your hand safe against the sharp edge.
Finally, clamp down the retaining ring between the lower and upper slitting knives so that the lower and upper knives from the circular butterfly knives are installed.

Precisely Correct the Slitter Knives

Each time an old sharpened knife or a new knife is installed, the height of the knife bed is supposed to be manually adjusted in order to fit the cutting amount.
This will prevent the accident resulting from the deeper cutting caused by the higher height of the replaced knives.
Here are the instructions:

Guarantee the cutting depth of the knives. Utilize a socket wrench to rotate the nut on the pulley's end face. Now, extend the knife bed to the low point and observe if the depth of the cutting knives is satisfactory - 0.5 to 1 mm.
In case just one end of the knife is in contact with the knives, the shaft behind the prominent frame should be adjusted.
Ensure that the cutting machine is in a tool-changing state. Initially, restrict the main motor, press and hold down the main motor stop button, and make sure that the main motor has stopped. Then, position the cutting tool selection switch in the middle tool changing position.
Remember that during the operation, you are not supposed to accidentally move or press the button. Plus, do not put your arm beneath the paper press and knife bed.
Be cautious about these institutions to successfully and effectively install and adjust the slitter knives. It will also boost the production success of processing and manufacturing.

Band or Blade Gap Adjustment

This gap is actually the horizontal distance between the band and blade prior to the loading of the blade against the band. A wrong blade or band gap can lead to an unsatisfying cut. However, a precise cut is pre-set at installation.
Sometimes, this gap needs to be reset when the blade unit is moved individually from the band unit. Remember that the band between the band and blade needs to be consistent throughout the slitters in order to guarantee a uniform side-loading force on all slitters.
Here are the steps to set the blade or band gap.

1. Prior to the adjustment or checking of the blade or band gap, ensure that these conditions are followed:

The slitters are loaded and engaged.
The winder is set at speed zero.
The slitter motors are switched off at the slitter motor overload panel. Plus, the control is locked out.

2. Now, enter the slitter section.
3. Deactivate the loading cylinder by closing the air valve, which is a blue or black air line. Doing so will unload the slitter blade from the band.
4. Measure the gap between the band and the blade. This gap is supposed to be set from 4 to 6 mm or 0.16" to 0.24". Remember that the thickness of the cord gauge supplied with the slitters can be employed for measuring the suitable gap. When the slitters are engaged, the blade overlaps the band. Afterward, the blade loads sideways against the band.

In case the gap is wrong, shift the blade unit to or away from the band unit until a suitable gap is achieved. Follow these instructions:

Switch on the local band locking switch. It will close the transfer rod air connection to the band carriage and will remain locked to the slitter beam. It won't budget with the transfer rod.
Shift the blade unit away or towards the band unit utilizing the appropriate slitter JOG switch. Band unit will stay in the original spot, and the appropriate blade unit will unlock from the slitter beam. Next, it will lock on the transfer rod, shifting With the transfer rod in the course it was jogged.
Let go of the switch when the preferred blade position is achieved. The blade unit will be unlocked from the transfer rod and relocked on the slitter beam.
Switch off the local band locking switch.
Permit the loading cylinder for the separate slitter to be fixed by opening the valve to the loading cylinder. The slitter blade will load against the band.
Escape the slitter section.
After making sure that no one is present in the slitter section, allow the slitter motors by switching them on at the slitter motor overload panel.

You are free to continue the operation.

Shear Angle

This is the angular relationship between the blade and the band. A suitable shear angle is 0.1° to 0.25° angle. It's advised not to exceed 0.05°. The best shear angle for a particular item is the maximum angle needed to slit the web.
Debris can settle between the blade carriage and blade holder with time, particularly after fixing the blade thickness. This can negatively influence the shear angle.
In case the angle is wrong, the maintenance team should fix it. Some solutions are replacing the blade holder, shimming beneath the blade holder, and cleaning debris.

Bottom Line

We have discussed basic information on how to install and adjust the slitter knives. You will now be able to execute the operation flawlessly.

＃Slitter Knife