Dies and tooling: Inspecting, cleaning, handling, storage and safety considerations

This article therefore aims to look at some of the main areas in pressure-sensitive label manufacturing - and in particular at the finishing end of the press - in which safety or damage risks have the potential to most likely occur. These areas and operations can include the following:

• Solid rotary cutting, embossing or foiling tools, as well as cylinders and anvils, can be quite heavy and a challenge to lift and move in or out of the converting line and andle safely without risk to the tool or operator

• Flatbed, rotary or flexible cutting dies have very sharp edges. Operators can sustain cuts and the cutting edges can be damaged during handling, set-up or adjustment

• Unpacking of incoming cutting dies and other tooling . and re-packing for storage or shipping . again has the potential to cause damage to the tool or operator during handling

• Cleaning and treating (oiling) prior to storage may also lead to handling or tool damage if not carried out carefully

• Operators may adopt awkward postures of back, neck and arms when inserting tooling or making machine adjustments, cleaning, and performing other tasks on the finishing line

• Loose object or hand tools, Allen keys, etc., left lying around the press may fall or be dislodged into machine working areas and cause serious tool or machine damage

• Items of clothing (hard metallic buttons) or jewellery (rings, watches, chains) worn by the operator during handling, installation or set-up may cause scratches, nicks or abrasions on precision tools, and possible injury to the operator

• Insufficient attention to set-up and running tolerances and pressures may lead to unit or tooling damage

• Poor tooling maintenance and storage conditions can lead to deterioration in tools over time.

There are always other areas where improved care and attention to tooling may be required, depending on the particular manufacturing or factory circumstances, but regular recording of the circumstances of tooling damage or operator safety issues should enable a converter to make further recommendations for handling, storage, or operator training.

The handling of tooling should not be just a secondary concern. The systems and procedures that are used to move and handle tooling as it enters, passes through, and departs manufacturing processes, machinery or fabrication areas can be a critical key to company productivity. The personnel that handle tooling need specific handling and usage instructions.

Often this training may be overlooked or considered secondary to the process of the machine set up. Good storage, transportation and handling systems used in label converting operations can significantly reduce costs, increase productivity and create a safer, more ergonomic production environment. 

Some of the key factors that need to be considered and addressed in the manufacturing and subsequent use of tooling in the label production plant are:

• Ensuring that there is no transportation damage, either from or to the manufacturer or within the converting facility

• The elimination as far as possible of any form of tool damage

• The reduction of production time and costs through the use of optimum handling, storage and usage procedures

• The provision of easy access to each individual tool

• The elimination or minimizing of any heavy or awkward lifting

• Obtaining a significant decrease in the chance of accidents

Quite simply, the aim should be to make life easier and safer for employees throughout the whole production environment and to minimize the risk of damage to precision engineered tooling and production machinery. A key step to achieving these aims is to implement improved training procedures and to better educate workers in how and where tooling damage is most likely occur.

TRAINING

All press operators and other employees involved in the handling and use of any form of tooling should be properly trained and competent. All training given should be based on relevant safe systems of work and should include a good working knowledge of the specific tooling to be used, it’s installation and set-up, how it should be handled safely, the operation of the press and converting units, the function and correct use of all the necessary controls, how to complete daily checks and what to do if any part of the machinery or tooling fails or becomes damaged. There should also be guidance on what the employee or operator needs to do if there are any concerns.

Training should also clearly identify which tasks an employee or operator should not carry out (i.e certain types of press or tooling repairs) as part of a wider set of ‘dos and don’ts’ incorporated into their training program. Retraining or refresher training for existing staff is also important if new safeguarding methods are introduced, and is particularly important if the safe systems of work are changed while the machinery stay the same.

Managers and supervisors have a crucial role in ensuring that safe handling, set-up, adjustment, maintenance and storage procedures are followed and that all operators and other employees follow agreed safe systems of work. Managers and supervisors also need to be competent to carry out their safety duties effectively and may themselves require further or refresher training where there are any changes to working procedures, systems or equipment.

GENERAL SAFETY AND HEALTH GUIDELINES

General principles for the avoidance of accidents in and around label and converting units and presses include:

• Know all the control points around the machine and how to stop in an emergency

• Check all guards are in position and working properly before starting the machine

• Wear suitable clothing. No loose clothing, ties, cuffs, etc., which may get caught up. Wear good boots or shoes

• Watch for oil, grease, ink or varnish around the machine and clean it up

• Keep workbenches and floor areas tidy and free from waste

• Check that tools and equipment are not lying on the machine when starting up

• Stop the machine before making adjustments and always use the correct tools for the job

• Never try to move obstructions or blockages while the machine is still in motion

• When working on a machine make sure that the power is shut off in such a way that it cannot be started accidently

• Keep all gangways and passages around machines clear of obstruction. Even small items may cause a fall

• Ensure all waste substrate is placed in the proper containers.

HANDLING GUIDELINES

Many printing industry accidents occur each year due to poor lifting, moving, handling, installing or adjusting of everything from reels, matrix waste, pallets, ink containers or machinery equipment. Yet the basics of lifting and moving heavy or awkward shapes are not always well explained. This point needs to be emphasised when lifting and handling cylinders, anvils, solid rotary cutting, embossing and foiling dies and tools, even flat dies, to ensure that back, arm, shoulder and fingers are not strained or damaged during lifting and moving. In addition, it is essential that cutting blades are protected at all times while handling, loading/unloading die-cutting, sheeting or perforating tools.

Fundamental points to remember in the manual handling and lifting of heavy dies or awkward or difficult shapes are as follows:

• Never persist in attempting to lift loads or heavy tools which cause a feeling of strain

• Get a good grip with the palm of the hands when lifting and handling, not just fingers only. Use protective gloves where thought necessary

• Do not stand holding heavy tools or loads. Rest on a bench or platform of a suitable height if any delay is unavoidable

• Never change the grip while carrying

• Use handling aids or hoists wherever possible

• Train workers to keep lifts below shoulders and above knee height

• Educate workers about risks to the low back related to handling and twisting.

It should be noted that the design of rotary tooling and converting units may typically require an operator to bend at the waste, twist and reach out to position, set and adjust cylinders, rollers, guides, rotary knives, etc.

Workers of course, do not usually hold these postures for any significant duration in their non-working life.

The frequency that workers on a converting line adopt these postures will depend on the particular product mix being processed and the make, model and year of the rotary die-cutting, embossing or foiling unit. 

Factors that may increase the risk of injury when carrying out this type of operation include:

• Duration of time in which awkward postures may ned to be held

• The frequency of adopting awkward postures

• The number of extreme postures adopted

• The accessibility to adjustment areas (machine design).

AUTOMATING THE HANDLING PROCESS

Some narrow-web press manufacturers have now incorporated innovative quick-change die-cutting units for very fast job change-overs. They are designed to save time on each job-setup, with easy handling of tools and less material waste.

These units feature an operator-friendly make-ready position, enabling the operator to set-up a magnetic base cylinder and flexible die while the press is running.

When the press is stopped, the previous cylinder is rolled to an unload position and the new cylinder is rolled into the running position – a process that takes no more than a few seconds.

The magnetic cylinders are equipped with bearing blocks that are automatically engaged and retained in the QC-station. Combined with precise tooling and automatic hydraulic loading, this allows the operator to change dies in seconds.

Other manufacturers have developed solutions such as a unique cassette and cart combination which allows the operator to load the die off-line and then conveniently load it into the die station without the use of a hoist. Dies can be changed in a little as 30 seconds. Also available are special mobile roll/cylinder lifts that have been designed for lifting, handling and rotating, everything from self-adhesive laminate roll stock to finished printed reels and dies. Such lifts can be equipped with multiple attachments, so providing a turn-key solution for a variety of converter handling needs.

PRE-PRODUCTION PROCEDURES

Prior to tooling being used it is advisable to go through procedures prior to loading the tool or dies in the press so minimize the potential for problems. In particular, all dies and cylinders – whether for cutting, embossing, foiling or sheeting/perforation – should be carefully checked and inspected for any visible signs of damage.

Where appropriate, all cylinders, rotary dies, and tools should be examined to ensure that gears are attached properly and secure. Setting-up of rotary dies will normally involve hand peeling a full repeat, pulling waste matrix and carrying out an ink stain test.

At all times dies and other tooling needs to be handled carefully, especially during loading, unloading and cleaning.

SETTING UP

After installing cutting, embossing or foiling dies it should be routine to carry out a check to ensure that they have been installed correctly, as well as undertaking all the necessary approval or quality checks before full production commences.

Press tolerances should be set accurately and checked periodically. When adjusted accordingly, it is possible to considerably increase the life of cutting, foil stamping, embossing and debossing dies. Also, be careful in make-ready. Scratching and dents can be avoided with just a little attention. With proper handling in all of these areas, it is possible to get the maximum life and usage from almost any type of die.

STORAGE OF CUTTING, EMBOSSING OR FOILING TOOLS

Unless they are only used for a one-off or specific operation, most types of tooling will require effective cleaning and proper storage after use so that they can be used again at a  time in the future. Steps to take should include:

• Inspecting the tool for any visual signs of damage that may need the die to be returned to the manufacture for remedial treatment before storing

• Clean or gently brush off any dust, hairs or other debris from the surface of the particular tooI, ensuring that it is handled safely. Avoid any possibility of damage to the surface of cutting, embossing or foiling edges or faces

• Protect the tool from moisture by spaying with a light coating of oil

• Use chemically treated wrapping tools

• Wrap the tool in a bubble pack

• Use the manufacturers shipping boxes for safe storage when possible

• Support rotary dies in blocks

• Ensure that nothing in the box comes into contact with cutting blades or the surface of embossing or foiling tools.

Brass, copper, or magnesium foiling or embossing flat dies can easily be scratched or nicked, so it is always a good idea to store flat dies in a foam envelope or bubble wrap of some sort. In addition, it is always recommended to store flat dies standing on end (vertical) rather than stacking them on top of one another. Some type of filing system, such as a filing cabinet with drawers, is best as opposed to stacking them up in a box or on a shelf.

For embossing/debossing flat dies that also have a pre-cast counter, it is recommended to re-pin the counters to the dies before storing them. Do not simply tape the counter to the die, since the die and counter can move or shift and cause wear on both the die and the counter. These wear or abrasion marks certainly will appear on press if the dies are not properly stored.

It also is recommended to consider handling copper and magnesium flat stamping dies differently than more expensive brass embossing dies, purging flat stamp dies in, say, two years and keeping brass dies for three to four years. If a flat stamp job is requested again after two years, it is much less costly to replace the flat stamp dies if the customer insists that they should not have to pay the cost to duplicate them.

Where flat dies are stored in large envelopes and filed vertically, then the layout or cut sheet from the job, plus the original Purchase Order information and a proof of the final product can be kept in this envelope, thereby storing the dies and keeping all of the job information in one place. If film was used with the job, filing this also is a good idea. Many times, the film is useful when registering the die to print or foil if the job is repeated.

In addition, it is always a good idea to make sure a die number from the manufacturer is kept in the storage envelope, storage box or file if it is not included on the die. It is much easier for the die manufacturer to make new dies, new counters, or even counter masters from old combination dies if it can reference this number.

DISPOSAL OF OLD DIES AND TOOLS

The recommended storage time for dies is usually between two and four years, depending on the tooling material used and the manufacturer’s recommendations.

Copper, brass, and magnesium dies are recyclable and most communities have a local metal recycler. Usually the price for recycled brass and copper is at a premium and the payback on these metals can be quite high. This should provide even more of an incentive to purge current die inventory and create an organized storage system.

CONCLUSIONS

Knowing the best procedures and practices to handle cutting, foil stamping and/or embossing dies has always been something of a gray area in the industry. It is hoped that this article has explained and clarified key aspects of the handling, storage, inspection and cleaning of label industry tooling, as well as creating some standard guidelines that can help manufacturers and converters to become more organized and communicate more efficiently with their customers.