Press Parts Cleaning

Maximizing Safety, Minimizing Liability,
and Improving Productivity

Press Parts Cleaning:

New Technologies Enhance Safety While Reducing Risks and Costs

To survive and succeed in today’s intensely competitive printing industry, converters must meet their customer’s high expectations for printing quality and economy, while at the same time satisfying increasingly stringent plant safety standards and environmental regulations. The cleaning of press parts is a key variable affecting the productivity and profits of any printing operation. Successful printers need to utilize press parts cleaning methods that are safe, efficient, and cost-effective.

The high flammability of conventional cleaning solvents, along with the fact that some of these materials are not designated by the EPA as hazardous substances, has led many printing companies to search for a practical alternative. The advent of water-based inks, adhesives, and top coats now also requires cleaning solutions capable of removing both traditional solvent based inks and these new formulations. Printing managers are also concerned with the escalating cost of solvents, the dangerous levels of VOCs generated during the cleaning cycle, the high cost of time and labor required for press parts cleaning, and the cost and liability associated with the disposal of solvent waste.

In this White Paper, we offer an overview of the primary issues associated with press parts cleaning, and discuss the technologies which have emerged to meet these changing needs. This information is offered to assist you in evaluating and selecting the optimum press parts cleaning technology for your application.

Threshold Limit Values (TLVs): The American Conference of Government Industrial Hygienists (ACGH) has set TLVs on the airborne chemical concentrations of chemical substances to which workers may be exposed. These limit values include time-weighted averages and short-term exposure limits. Time-weighted averages define the average concentration to which workers may be exposed 8 hours a day, 40 hours a week without adverse effect. Short-term exposure limits define the concentration to which workers may be exposed continuously for short periods of time without adverse effect.

Makeready worker safety: The United States Environmental Protection agency, under authority of the Clean Air Act, is moving quickly to enact and enforce more stringent regulations on the use of Volatile Organic Compounds (VOCs) in industrial plants. Most traditional press parts cleaning solvents are listed as harmful VOCs and pose significant risks to the health and safety of makeready workers.

Improving Press Parts Cleaning Safety

Open vats of flammable and caustic materials pose a serious threat to the health and safety of press room personnel. The exposure of employees to hazardous solvents is now subject to Threshold Limit Values (TLVs) established by the American Conference of Governmental Industrial Hygienists (ACGIH). Thus, continual employee exposure to aggressive solvents can create enormous risk for a company, and can include long-term and largely unpredictable legal liability. A single serious injury, or the threat of lawsuits from even low-level exposure of makeready workers to VOCs, can result in compensatory and punitive damage awards. Further, the threat of potential fires and the subsequent property damage exist with the use of flammable materials. Any of the above scenarios can result in losses in the millions.

In addition to posing very real risks to company employees and property, hazardous solvents can increase operational costs, or damage and shorten the useful life of press equipment.

A Safer Solution

Fortunately, innovative press parts cleaning systems have emerged which employ a reusable, non-hazardous cleaning agent in a safe, closed-loop wash cycle. The cleaning agent is a non-flammable solution which quickly and efficiently cleans both solvent-based and water-based inks. Thus the cleaning agent improves workplace safety, boosts press parts cleaning performance, and reduces overall operating costs.

Reducing Environmental Liability

Traditional manual and automated cleaning methods do not distill or reuse cleaning solvents and require very large volumes of virgin stock materials. The new SARA Title III Hazardous Chemical Inventory regulations require strict planning and reporting when firms store and use hazardous materials exceeding specified quantities. Most traditional press parts cleaning solvents are also classified as Extremely Hazardous Substances (EHSs) under SARA III, and must meet the most stringent use, disposal and disclosure standards.

A sometimes overlooked risk of using hazardous materials is the potentially high cost companies pay in customer and community "goodwill" if they cause a serious environmental incident.

Every printer serves a community, and in today’s business and political climate, no company can afford the negative publicity resulting from employee injuries or environmental contamination.

Environmental regulations: Title III of the Superfund Amendment and Reauthorization Act (SARA) requires companies to plan and report on the storage and release of certain hazardous chemicals. Most traditional press parts cleaning solvents are categorized as "extremely hazardous" under SARA III.

Reduce waste up to 100%: Enclosed wash systems are now available that reuse a safe, non-flammable cleaning solution then distills the dirty solution to recover over 90% for continued use. A secondary drying process allows the recovery of up to 100% of all cleaning solutions.

Environmentally Friendly Solutions

For the more environmentally friendly cleaning method, printers should look for closed-loop cleaning systems without open or top load tanks. The selected system should be designed to minimize waste and to use non-flammable, non-hazardous, recyclable cleaning agents. A system featuring an automated wash and recovery process is best, since it ensures the least amount of losses to the environment.

Lowering Operational Costs

Manual washing, using traditional flammable solvents, puts employees at risk and results in large evaporative losses. While it may be an option for small volume cleaning applications, the risk to employees, the high expense of labor, and cost of virgin solvent make manual washing the least desirable alternative for most printers. Automated cleaning using traditional solvents yields increased productivity with lower labor costs, but poses the greatest safety risk due to the creation of volatile air/fuel mixtures inside the washing machine. Automated cleaning with traditional solvents also requires large supplies of expensive virgin solvents, and creates dangerous and costly used-solvent disposal problems.

An Investment in Productivity

As illustrated in the accompanying Cost Comparison Per Cycle chart, using today’s alternative non-hazardous cleaning agents with a closed-loop wash system is by far the most economical way to clean press parts. A closed-loop system is capable of reducing operating costs by 50% when compared to flammable, automatic cleaning methods, and by as much as 400% when compared to manual press parts cleaning. The alternative cleaning agents can also clean both solvent-based and water-based inks simultaneously, eliminating the cost of separate cleaning cycles.

Partnering with a Professional

The selection of a parts cleaning system for your operation requires that your supplier have a complete understanding of your needs.

There are four distinct functional areas which figure prominently into the system selection process and which, when each is examined, should permit the development of a thorough understanding of your operational requirements. If you have chosen a reputable supplier with in-depth professional expertise in wash systems, the supplier will work with you to evaluate these four functional areas before recommending a parts cleaning system.

Based on these cleaning requirements, your vendor should help you evaluate different cleaning agents to determine which ones best suit your needs. Once a cleaning agent is selected, a secondary evaluation and test should be performed to determine the proper distillation/recovery equipment.

Both evaluations should be conducted by a firm which is knowledgeable about the testing, washing, and distillation process.

Operation, the human factor, refers to the specific requirements and limitations of the operator. The operator interface dictates the type of controls, the degree of automation, and specific hardware requirements. Unique facility and procedural stipulations may dictate the logic and control scheme specifications necessary to ensure a successful operation.

The importance of communication between the buyer and the supplier is critical in this portion of the project. Safety and automation should be the two primary concerns of the evaluation.

The DPU selection process must evaluate the physical parameters of the application as well as the larger environmental, safety and economic issues. This selection process takes into account the characteristics of the cleaning agent and the operational requirements.

Computer modeling methodology:

Provides a projected simulation of your distillation cycle, the actual solvent output rates, and solids to be disposed of. Your company’s computer modeling graph will be a unique reflection of your distillation cycle.

On large scale systems, the software should provide graphic operator interface, with charts and trending for system management. In addition, it should include comprehensive diagnostics. On small scale systems, it should provide redundant safeties and simplicity of operation.

Once your supplier understands your process, your operation, and your unique hardware and software needs, a proposal can be generated for a parts cleaning system that provides optimum performance and improves your existing operation.

The Advantages of a Closed-Loop Press Parts Cleaning Systems

To maximize the safety, productivity, and environmentally friendly operation of your press parts cleaning operation, a closed-loop automated wash system with a built-in recovery unit is the optimum solution for today’s printers. Such a system, featuring a washer, a dirty solvent tank, a solvent recovery unit, and clean solvent tank, should have all components hard-piped together to eliminate the use of drums or barrels.

Look for systems in which microprocessor-based controls pump the cleaning agent between the tanks, washer, and solvent recovery unit. These systems eliminate the need for an operator to be present during the cycle, and are available with fail-safe controls in the event of a loss of power or air pressure. Optimum systems features are indicated in the diagram below.

DIRTY SOLVENT TANK
     • Contains dirty solvent until it enters the solvent recovery unit for recycling
     • Meets NFPA 30, API valve standards, and B31.3 process piping standards
     • Conservation and emergency vents meet code and minimize evaporative losses
     • Cleaning agent recirculation loop keeps solids in suspension
     • Cone bottom for easy cleaning
     • Carbon steel or stainless steel construction
     • Level indicators provide feedback to the distillation and wash systems

SOLVENT RECOVERY UNIT
     • Processes the dirty cleaning agent and returns recovered agent to the clean solvent tank
     • Automated control monitors output and adjusts process times for various solids loading
     • Provides consistent still bottoms to reduce disposal costs
     • Hard plumbed and completely automated
     • Designed for Class I, Division I areas
     • Features a nitrocellulose "prevent" and "quench" package
     • Stainless steel construction
     • Sized to match the requirements of the wash system
     • Special design for high solids
     • Can recover up to 100% of the cleaning agent

CLEAN SOLVENT TANK
     • Stores clean solvent
     • Stainless steel construction
     • Meets NFPA 30, API valve standards, and B31.3 process piping standards
     • Conservation and emergency vents meet code and minimize evaporative losses
     • Level indicators provide feedback to the distillation and wash systems

Implementing a Cleaning System

Once funding has been approved and you have contracted the purchase and installation of the cleaning system, you are ready for implementation.

This includes installation, inspection, equipment checklist verification, equipment commissioning, system operation, operator training, specification validation, and systematic follow-up.

A vendor interested in you long-term success will have the appropriate team of people available to advise you and your contractors during all stages of installation and implementation. The team should include your salesperson and field service technicians, plus mechanical, electrical, and chemical engineers.

To ensure the successful start-up of the system, the field service staff should review the physical installation and start-up equipment. They should encourage all employees responsible for operation to participate in the start-up. Thorough training is a critical part of the long term success of the project.

Implementation is not just the start-up and warranty, it is a product stewardship responsibility that the manufacturer must commit to and support for the life of the product. Success is achieved when your wash system is operational and is cleaning parts in the manner that was prescribed in the project justification. By following the steps we have outlined in this White Paper, you will be on the way to achieving the company’s expectations for parts cleaning as well as your goal for project success.

About PRI

Progressive Recovery, Inc. (PRI) in North America’s leading manufacturer of solvent recycling systems. In 1984, PRI introduced the SWS-400 End Opening Door System, a Total Wash System with automated spray cleaning. The system washes, rinses, and dries press parts in a safe, closed-loop cleaning cycle. It uses non-flammable, non-hazardous cleaning agents and features a distillation process for recycling the agents within the closed-loop design. Leaders of the converting market have named PRI’s Total Wash System as the Best Available Technology (B.A.T.) to emerge from efforts to produce an environmentally friendly press parts cleaning system.

With a complete line of cleaning systems supported by engineering, design, manufacturing, quality assurance, service and after-the-sale support, PRI has contributed innovative solutions to cleaning problems at both Fortune 500 clients and privately held companies.

The key to PRI’s effectiveness has been the utilization of methodology which allows us to truly understand each customer’s requirements and apply the optimum solution. Our methodology is as follows: