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Page 1: 87 15inch Wagner Coater

Packaging Operations

Sheet Coater

Wagner

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Human Resources ______________________________________________________ To add value and lead by example

Training & Development Broomfield, Colorado 80021

Ball Packaging Operations

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Note This manual has been developed for use with Ball training programs. It covers basic machine

principles, concepts, and typical procedures. It is not meant to replace Original Equipment

Manufacturer (OEM) manual(s). Do not use it when ordering parts—refer to the OEM manual for

your specific machine and model.

Important

Plant Standard Operating Procedures (SOPs) or Work Instructions (WIs) should always take priority

over a typical procedure in this training manual, as they will be specific to your plant and machinery.

Proprietary Notice

This material contains subject matter that is proprietary to Ball Corporation, and that is protected under

the copyright laws as unpublished works, under the trade secret laws, and under the terms of written

license agreements with Ball Corporation. No portion of these materials may be copied or used for any

purpose except as permitted under any written license agreement with Ball Corporation.

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SECTION PAGE

Specifications……………………………………………………………………………5

Safety Limit Switch Arrangement ………………………………………………………7

Principles of Operation…………………………………………………………………..8

Material Flow Diagram.................................................................................................…10

Backlash Gear Arrangement........................................................................................…..11

Operating Controls and Procedures Chart ....................................................................…12

Install Composition Roller............................................................................................….13

Setting and Adjustments…………………………………………………………………26

Isoblade Scraper System…………………………………………………………………27

Suggested Coating Handling Procedures………………………………………………..45

Changeover Instructions ..............................................................................................…..44

Preventive Maintenance....................................................................................................47

Line Greasing……………………………………………………………………………47

Troubleshooting...............................................................................................................48

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Description and Purpose

The Wagner 15 x 44 Sheet Coater is a machine used to apply coatings to sheets through a series of

rollers, at a precise time in precise locations and specified thicknesses. The coater is used for straight

coating applications behind an automatic feeder.

Capacities

Minimum sheet size 19" x 24" wide Maximum sheet size 42" x 42"

Speed Ranges

Maximum 100 sheets per minute Minimum 50 sheets per minute Rate of feed

is determined by the coating material and bake time.

Basic Dimensions and Weights

Approximate dimensions 14' long x 7' wide x 8' high Approximate weight 23,000

pounds

Motors and Drives Data

Drive unit is furnished to specific requirements of the whole system. Drives must be synchronized.

Normal ratings: 1,800-2,400 rpm 10 hp.

Services

(see Basic Assembly L115000-36 for locations) Air 45 PSI minute Exhaust

Optional by customer

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Figure 1

Figure 2

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Drawing D107100-18

Note: There is no standard wiring diagram for the coater alone. The coater is wired into the system for

the complete line.

Figure 3 Switch 1 Jam stops 2 Hand wheel guard 3 Composition roller guard 4 Composition roller gear guard 5 Composition roller lift When any micro switch is energized, coater stops operating.

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1 When the sheets reach the coater from the sheet feeder, slow-down magnets control the sheet to achieve a gentle takeover by the coater lug fingers.

2 Lug fingers take the sheet to the register fingers. 3 Register fingers take the sheet to side gauges that register the sheet precisely. 4 The upper roller, or composition roller, applies the coating, which has been fed by the anilox

roller. 5 The lower roller, or scraper roller, acts as a backup. 6 The sheet passes over the discharge rollers and out.

Note: The minimum stopping period should be one complete revolution of the composition roller; at

100 sheets per minute, this would be 0.6 seconds.

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Figure 4 Sheet Coater Wagner

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Material Flow Diagram

Isoblade Scraper Arrangement

Coating is applied to the scraper roller through a separate connection from pump to lubricating channel

assembly. “Paint” scraper removes coating material.

Thinner is applied to the scraper roller through the felt pad bar assembly and is removed by the thinner

scraper.

ISOBLADE SCRAPER

Figure 5

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Backlash Gear Arrangement

Figure 6

The backlash gear arrangement consists of a hardened steel plate gear mounted on the upper

intermediate gear and in mesh with the hardened composition roller gear. The plate gear is centered

around the hub of the upper intermediate gear and should bear against the lead surface of the

composition roller gear tooth while the upper intermediate gear tooth is driving the composition roller

gear. This scissor action eliminates the backlash between the gears.

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There are three spring housings, each with an adjusting screw, and the pressure can be determined only

by experience and is dependent on the speed of operation and the pressure on the composition roller.

This pressure should not be so great that it causes binding of the teeth, nor so small that the scissor

action is ineffective.

Operating Controls and Procedures Chart

To set coater into operation:

1 Insert proper composition roller and bring it into operating position. 2 Install correct anilox roll for film weights. 3 Bring scraper and pans into operating position. 4 Set feed board for proper sheet length. 5 Bring #1 feed fingers to “timing” position. 6 Set side gauges at “timing” position. 7 Adjust pumps.

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Figure 7

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Figure 8

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Figure 9

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Figure 10 (refer to drawing on page 11)

Figure 11 (refer to drawing on page 13)

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Figure 12

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Anilox System

There are two blades incorporated in the unit, one plastic blade at the bottom of the chamber to scrape

off the excess coating from the anilox roller and one plastic blade at the top of the chamber to contain

the coating within the chamber.

Figure 13

Two nylon end plates are fastened at each end of the chamber and slide over the face of the revolving

anilox roller to totally enclose the coating within the chamber.

There are two drain holes in the anilox chamber for returning the coating back to the lacquer tank.

The bottom return hole has a flow control spindle to make sure the chamber is full of coating so as

to prevent starvation.

The catchment tray supplied is used as a return to the lacquer tank for the coating.

Setting the Blade to the Anilox Roller

Rotate both of the adjusting handles (1) counterclockwise until both blades are just touching the anilox

roller. Start the anilox roller rotating, and then turn on the lacquer pump to send coating into the blade

chamber. Wagner Sheet Coater

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Figure 14

Set the flow into the chamber with the flow control lever (it is important that the flow is not at full

pressure as this will cause flooding). The coating should return out of each end plate at the speed of a

slow running tap.

Make final adjustments to the pressure of the blades by turning the adjusting handles (1) by

approximately half a turn counterclockwise. Do not have excessive pressure on the blade as this wears

the blade prematurely. Tighten clamping screws (2).

The blades are now set and do not need to be adjusted when cleaning or changing rollers. Sheet Coater Wagner

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Figure 15

Figure 16

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Setting the Anilox Roller to the Applicator Roller

Figure 17

Make sure the quick release handle (3) is locked in the UP position. Undo locknuts (4). Turn knurled handles (5) clockwise to move the anilox roller and chambered blade together onto the applicator roller. Once set at the required pressure, tighten the four locknuts (4).

To remove the anilox roller from the applicator roller, place the quick release handle (3) to the DOWN

position. This will separate the rollers by approximately 0.25" while keeping the gears in mesh.

Figure 18

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Sheet Coater Wagner

Replacing Blades

Release the clamping handle (6) and rotate the chamber to its horizontal position. Loosen the blade

clamping screws (7) and remove the old blade (protective gloves should be worn at all times when

handling blades).

Figure 19

Cut a new blade to length, ensuring the edges are as square as possible. Care should be taken to make

the blade as close as possible to each nylon end plate, but not too long as to cause a ripple in the blade. Wagner Sheet Coater

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Figure 20

Position the new blade under the clamping strip; ensuring the blade is pushed back as far as possible to

the step in the blade housing. Retighten the blade clamping screws. Repeat the procedure for the other

blade.

Rotate the chamber to its original position and retighten the clamping handle (6).

Changing the Roller

Retract the anilox roller from the applicator roller and wrap around the protective blanket provided.

Screw the “eye” bolts through the cap and into the roller at each side. Lower the hoist beam and put the

hooks through the “eye” bolts. Remove the two caps and lift out the roller into the trolley.

Remove the “eye” bolts and caps and place in the anilox roller required for the next job, making sure

the arrows on the caps are facing outward. Lift the roller into the unit, ensuring the drive peg at the

operator’s side is positioned in the hardened sleeve. Replace the screws in the caps and release the hoist.

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Figure 21 Cleaning the Unit

Pump solvent through the unit while the chamber is in the coating position and the machine is running.

This will clean the pipe work, blade, and anilox roller.

Remove the infeed pipe from the back of the blade before retracting the blade. Wipe the anilox roller,

chamber, and catchment tray with a solvent wiper. While cleaning the chamber, wear protective gloves

at all times.

For more detailed information, see the “Wash Up” section of this manual.

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1 Adjusting handle 4. Lock nuts 2 Clamping screws 5. Knurled handles 3 Quick release handle 6. Clamping handle

Figure 22

Important: Perform all actions in the manner stated in this manual. Ensure you know how to stop the machine. Keep the anilox unit and surrounding area clean and tidy. Wear protective gloves when handling blades or cleaning the chamber.

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Figure 23

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Isoblade Scraper System

The Isoblade scraper system uses a sharpened steel blade submerged in a reservoir of

coating material to clean the scraper roll. Although similar to the LTG scraper system, there are a few differences. The scraper blade is separate from the chamber. The front wall of the scraper trough

(chamber) is a spring steel (referred to as a “spring blade”). The scraper blade is mounted independently a support arm which traverses the coater. Air cylinders push the spring blade against the scraper blade at a stroke, preset by Crabtree, when they install the unit. Scraping air pressure is adjustable and can be set to a minimum value to give reliable scraping while maximizing roll and blade life. This arrangement has the major advantage in that the loading and consequently the wear across the blade are equalized.

Each new blade has to be bedded in, then the scraper blade should not be disturbed

unless it is being cleaned. The trough will move away from the blade for cleaning purposes. The trough, blade holder and support bar should be cleaned at each wash up.

During a wash up, the coater may be inched slowly, when the trough is empty, in order

to clean the scraper roll. This will probably require one rotation of the scraper roll. In general, however, the machine should not be started unless the tough is mated to the scraper blade, and the trough is filled with material.

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Scraper Blade Change

NOTE: The blade, blade holder and support beam MUST be regularly cleaned. Changing the blade 1 Stop the machine. 2 Proceed as for a job changeover, including wearing personal protective equipment. 3 Remove the scraper trough drain plug and allow the trough to drain. 4 Retract the trough by simultaneously pressing both pushbuttons on the control station

for a minimum of 5 seconds. 5 Fit a protective cover onto the working edge of the blade.

WARNING Sharp edge. Will sever hands. Fit the protective blade cover to the blade before handling. Fit and use the supplied handles to carry the blade and holder. Always use protective gloves.

6 Using the supplied handles pass these over the trough. This procedure requires 2 people, one person for each handle.

7 Locate toggles in blade holder holes at each side and ensure the toggles drop to lock the blade on.

8 Before lifting the blade and holder, recheck to ensure the blade protection strip is fitted. 9 Loosen operator side clamp. 10 Move the blade holder to the operator side first to disengage drive side location pin by

sliding along the beam. 11 Lift up the non-operator handle first to raise this side of the blade holder up and towards

the trough and follow through with the operator side handle. Drawing the blade and holder over the trough and under the delivery belts. The blade holder should be guided over the top of the trough between the side cheeks.

12 The blade holder should be placed on a level surface before the handles are removed. 13 See procedure for changing the blade and setting it in the blade holder.

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14 This is the time the trough cheeks, spring blade, scraper blade holder, the scraper

blade support beam and stops can be thoroughly cleaned. 15 Before replacing the blade and blade holder back on to the support beam ensure the

blade holding handles are securely fitted with the toggles engaged and the blade protective strip is fitted.

Notes concerning blade bedding-in During the process of blade bedding-in the surface contours of the roller and blade edge become microscopically matched, mating together perfectly. During this period of blade bedding-in the blade and roller wear rates are extremely high possibly ten times or more that for normal running. The bedding-in period is therefore the most damaging to blade and roller and should be minimized. That is it should be done only once per blade. Every time the blade is moved away from the roller or is even slightly disturbed the blade has to be bedded-in again at high wear rates. This will dramatically shorten the life of the blade and the roller. If this is common practice then blades will often be worn out before they are bedded-in. Blades should not be moved or even microscopically disturbed once they have bedded-in. It is therefore good practice, if there are many changeovers, to leave the blade against the roller without reducing the air pressure. In this way it is guaranteed the blade will not be disturbed and will not require bedding-in. A good indication as to whether the blade has been worn out is to measure the width of the wear land across the tip of the blade. This is the worn mating surface with the roll. If the wear land has increased to 0.0008 inch (0.20mm) then the blade is worn and should be reground. Less than 0.0005 inch (0.13mm) and the blade could be used again. Replacing the blade and bedding-in The blade and blade holder are mounted on the crossbeam with the M8 cap screw heads facing the compression roller. The holder is axially positioned between the blocks on the beam, the non-operator side block is factory set to the edge of the compression roller and should be used as the datum side. 1 Make sure the trough is in the retracted position. 2 Ensure the blade has its protective cover fitted to avoid damage to the blade’s edge

and to avoid accidents. 3 Pick up the new blade and holder with the handles, making sure the bolt heads will face

the roller and the nuts or clips on the handles are secure.

4 Move the blade holder into position by using the handles to maneuver the holder under

the trough and up on to the beam. The reverse procedure from removing the blade. Take care to protect the blade.

5 Engage the blade on the beam with the drive side firmly against the datuming (non-

operator side) stop, with the pin engaging in the slot/hole of the blade holder.

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6 Some versions of the blade holder (fitted with a hole) require the feed-side stop to be

moved and positioned to engage its pin into the blade holder’s hole. The stop should then be locked in position.

7 Remove the protective blade cover prior to operation on the blade against the compression roller.

8 Simultaneously press both pushbuttons on the control station for a minimum period of seven seconds to engage the trough.

NOTE Air cylinder rod lengths are factory set so that at 80psi (5 bar) excessive movement of the actuation levers are prevented. This limits the blade deflectors to between 8 to 9mm at the spring blade tip.

9 For bedding-in, start initially at 30 psi and run the roll slowly at first building up speed to 6000 sph. After one minute increase the pressure to 40 psi. After a further minute at this speed increase the pressure to between 50-60 psi (3.5-4 bar). If there are lines of coating showing on the roller caused by nicks in the blade, increase the pressure further to 80 psi and run it for as long as it takes to clear the line. Badly ground blades with nicks could take up to one hour to clean the roller.

10 Drop pressure to just stop lacquer passing. This may only be 20 psi for running. 11 As the blade wears the pressure may be increased.

CAUTION The blade will be damaged if the machine is run with the blade pressurized and the trough empty or filled to below the blade tip.

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SETTING THE BLADE The blade will require resetting after regrinding or replacing. A fixture and setting gauge are provided to accurately set the scraper blade, this fixture should be permanently mounted on a bench or table. It is advisable to mount the setting fixture at an angle so that the blade holder drops down to the datum rollers. 1 Place the blade and holder on the fixture with the ‘V’ of the holder against the two end

gauging blocks and clamp in position with the toggle clamp. 2 Remove the protective cover from the blade. 3 Loosen the clamp screws. 4 Turn the adjusting set screws to set the blade to the gauge. 5 Align the blade to the holder on the right hand (drive-side) edge, so that the blade and

holder edges are flush. (Some setting fixtures are fitted with a datum stop). 6 Retighten the clamp screws. 7 Replace the protective cover.

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OPERATION OF PNEUMATICS Sequence of Operation 1 The green indicator on the switch console must be indicated before the cylinders can

be actuated. 2 Press both switches simultaneously and keep depressed for SEVEN seconds. 3 The blade will now be deflected against the compression roller. 4 If the sequence is interrupted before the time delay has elapsed (i.e. releasing one of

the switches) the cylinders will exhaust and the scraper will return to its rest position – you should now continue from step 2 again.

5 When the trough is engaged it can be returned to its rest position by pressing both

switches simultaneously for FOUR seconds until green indicator goes off and then release both switches.

6 The green indicator should be present in order to start sequence again.

IMPORTANT NOTE

If step 5 is interrupted, the cylinders will retract but the system will require resetting. Pressing both buttons simultaneously until green light goes off and then releasing buttons can reset it. The system is now ready to start the sequence.

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Set Feed Board for Proper Sheet Length

Figure 29

Figure 30

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Set the Slow-Down Magnets and Adjust the Stop Magnets

Figure 31 Note: The proper speed of the slow-down magnets is the speed required to keep

the back edge of the sheet in contact with the face of the #1 feed finger during the

gauging cycle. It should not be so fast that it pulls the sheet away from the finger nor

should it be so slow that it causes the sheet to buckle. The proper speed can only be

obtained by experience through the trial and error method and is dependent on such

factors as sheet size, sheet weight, and speed of feed.

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Adjust Speed of Front Slow-Down Magnets

Figure 32

Figure 33

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Figure 34

Setting #1 Feed Fingers

For “A” gauging, the outer two fingers should be used and the center finger retarded approximately

1/8". For “B” gauging, the center finger is used while the outer two are retarded 1/8".

Figure 35

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Figure 36

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Taking Up Slack in #1 Feed Fingers

Figure 37

Figure 38

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Setting Pneumatic Side Gauges

Figure 39

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Figure 40

Setting Side Gauges for “A” Gauging

Figure 41

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Note: The #2 feed fingers must be repositioned for every change of sheet length.

Figure 42

Figure 43

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Figure 44

Note: The tension on the #2 chains will be maintained automatically by the counterweights at the front

end of the machine. Wagner Sheet Coater

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Figure 45

Figure 46

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Setting Backlash Gears

This is only done upon replacement. Contact someone with previous experience.

Figure 50

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1 Clean the coater thoroughly between different coatings. 2 Read and refer to the product data sheet and the material safety data sheet. 3 Check the date of manufacture of the coatings. 4 If the material is stored outdoors or in an unheated area, allow the material to come up to room

temperature before using, or thinning may be required. 5 Mix the coating thoroughly per instructions. 6 Use only clean tools and vessels for mixing and transporting coatings, thinners, and additives. 7 Check viscosity of each drum and adjust as required. 8 Use only approved thinners and additives. 9 For all additions use accurate measurements and blend thoroughly. Use the amount

recommended. 10 Add thinners and additives to coatings under agitation or as recommended. Each addition should

be stirred in separately. 11 Check viscosity, coating weights, and oven settings periodically. 12 Visually inspect coated plate periodically. Run standard QC tests to assure that fill properties are

acceptable. 13 Coating and thinner should be at room temperature for best results.

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To Change Sheet Size 1 Sheet length adjustment may be made by moving feed board to coincide with scale located on

the operator’s side of machine. 2 Adjust side gauges. 3 Run sheet and inspect lay of coating; for front to rear change adjust composition roller, for side-

to-side change adjust side gauges. Run sheet and check film weight, adjust per quality assurance standards.

4 Run more sheets adjust speed of slow-down magnets for smooth take over by lug fingers. 5 Adjust timing, if needed. To Change To End Plate

Change roller and feed board (no side guides are needed since registering of the sheet is not

necessary). Side gauges may be used for pre-gauging.

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Line Greasing

Daily Per Shift

1. Anilox system.

Weekly

1 Registration assembly. 2 All drive gears (open gear grease). 3 Feeder. 4 Take-away bearings/pulleys. Monthly

1 All grease fittings. 2 Check/fill all gearboxes (feeder and oscillator use worm gear oil, all others use 90 weight). 3 Slow-down magnets.

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Problem Probable Cause Remedy

Failure to register front and rear

Composition roller not positioned properly in relation to sheet.

Adjust composition roller clamping device.

Excessive backlash in the anti-backlash gears.

Adjust anti-backlash gears.

Looseness in the composition roller mechanism.

Tighten up all parts in the compo-sition roller gear-clamping device.

Feed board not set at proper scale and location in relation to sheet size.

Adjust feed board to size of sheet.

Cocked sheet because one feed finger is ahead of the other.

Adjust feed fingers to be directly in line with each other.

Stop magnets are set too high or too low.

Lower or raise magnets.

Improper take over between lug and feed fingers.

Align lug chain so that each set of lug chain fingers exactly align. When chain lengths differ, chain wear is probably the cause; there-fore, new sets (both sides) are recommended.

Pusher chain tension. Adjust chain tension. Gearbox possibly bad.

Pusher head assembly. Inspect assembly for stripped bolts, broken pins, or broken spacer between head and chain.

Out of register plate. Check with lead man/experienced operator.

Failure to register side to side

Improper setting of side gauges. Reset side gauges. Check air pres-sure setting (should be 1-5 pounds).

Improper setting of pre-gauging. Reset pre-gauging. Out of register plate. Check with lead man/ experienced

operator. Dirty backs (smudging of sheet)

Scraper knife not cutting (removing paint/coating from scrapper roller).

Change thinner (depends on con-tamination level). Check for blown felt, change if necessary. Pull scraper knife, clean/ sharpen as necessary. If thinner gets contam-inated quickly, sharpen coating knife.

Dirt or foreign matter on chrome slides, belts, and chains.

Clean off with solvent.

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Problem Dirty backs (smudging of sheet) (continued)

Probable Cause Excessive roll pressure.

Remedy Adjust roll pressure. Note: Some high film weight coating will transfer to backs, example 181444 (buff).

Bleeding Incompatible system.

Almost always requires new coating or ink selection.

Solvents of varnish dissolving ink vehicle.

Lower solvent power of varnish solvents.

Blocking Under cure of coating on either side. High winding or stacking temperatures. Stacking too high. Winding too tight. High humidity. High film weight. Excessive lubricant.

These remedies are self-evident.

Poor weight distribution on pallet bottoms. Reduce or replace lubricant.

Blooming Very incompatible internal lubricant. Reduce or replace lubricant.

Bubbling

Poor solvent balance. Excessive turbulence. High surface tension of solution.

Thinning. Reformulation. Reduce line speed. Reduce turbulence.

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Burning Over baking Reduce bake.

Chattering Cratering (fisheyes)

Partially or totally overcooked batch. Over-aged batch. Over-aged premix. High viscosity. Gear slippage. Bad plate. Lubricant incompatibility. Solution contamination.

Thinning. Blend with fresh batch. Prebake plate. Replace with fresh solution.Thinning. Additives modaflow.

Crawling Poor solvent balance. Oily plate. Low wetting tension plate. Excessive film weight. High first zone air velocity.

Reformulate. Prebake plate. Thinning. Reduce first zone temperature.

Wicket marking Hot wickets Dirty wickets. Under cure of backside coating. High film weight with backside coating. Back side coating too thermoplastic.

Lower preheat zone. Change sequence.

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