- April 01, 2009, By David Argent Contributing Editor
Management of ink rooms takes many forms and may be controlled and staffed by the converter or by the ink supplier and sometimes a combination of both. It is always a complex operation dependent on quality procedures and processes.
The workflow below is a much simplified macro view of ink operations. Based on quality systems in place, periodic audits are required.
Auditing is one of the most powerful monitoring techniques and an effective way to avoid complacency and to highlight any deteriorating conditions, especially when the auditing focuses not just on compliance but also on effectiveness. The audit may be conducted by internal auditors, but an external audit led by the ink supplier often can add more insight. The ink supplier would have the advantage of benchmarking criteria from other converting facilities.
The ink department personnel should have numeric measures and goals to guide their performance. These measures should support the goals of the converter, especially in terms of cost, quality, and productivity. The ink department manager should be able to explain to converter management any trends in these indicators and make recommendations on remedial action if required. Here are some examples of mostly numeric performance measures:
Systems and Procedures
The ink room lab, mixing room, storage, and staging areas should be audited for safety compliance. Frequent lapses in this area are failure to clamp mixing vessels and lack of familiarity with emergency procedures.
- Ink Room Color Standards
Issues here normally concern absence of written procedures for generating, storing, and retiring physical and electronic color standards.
- Proofing System
This can be a very chaotic area in trying to simulate press color with a lab proofing method. This will be explored in next month's column.
- Ink Mixing and Staging
This is covered by the well-used phrase, “right amount of the right ink to the right press at the right time.” There usually is evidence of too much or too little of sometimes off-shade ink being delivered to the press. This shows up in performance measures.
- Inventory Control
For gravure and flexo inks, the biggest problem is managing press returns. Short runs lead to more ink being returned to the ink room than actually consumed on the job.
- Job Usage Records
Correct data on ink use makes job costing accurate and allows dependable job history to be accumulated and an ink cost forecasting model to be developed.
It is evident that an audit is only as good as management commitment to follow up with corrective action. My experience has shown that many problems revealed in an inkroom audit are symptoms of larger concerns for the whole converting operation. An example of this will be discussed next month under the title, “Why So Many Anilox Rolls?”
|Inventory Levels||Pounds and Dollars of Fresh and Rework Ink in Stock|
|Consumption||Pounds and Dollars of Fresh and Rework Ink Consumed|
|Consumption Unit||Pounds and Dollars of Ink Consumed per Unit, e.g., per 1,000 cartons|
|Ink Related Downtime||% Jobs Toned||Inks Toned at Press Startup|
|Toning Time per Incident||Average Time To Get on Color|
|Product Complaints||Quality Complaints on Ink Performance|
|Training Provided||For Operators on How To Maintain Ink on Press|
Process improvement expert David Argent has 30+ years of experience in process analysis with particular emphasis on ink and coating design and performance. Contact him at 314-409-4304; firstname.lastname@example.org.