Simplified rubber compound management.

Before personal computers came into widespread use, rubber compounding had always been perceived as more of an art than a science. Formulations were traditionally maintained in a manual book format, While this provided some basic documentation, there was simply no easy way for the rubber chemist to ask "what if" questions and do experimentation to design new recipes. On a daily basis, the rubber chemist has to deal with a large volume of chemistry data, including a wealth of raw materials, test conditions and physical properties associated with formulations. There is simply no way to effectively integrate all of this information with a paper based system.

With the advent of inexpensive personal computers, rubber chemists could finally begin to work with their formulations in a more interactive, personalized manner. Typically, the formulation and rubber recipe data is managed using off-the-shelf software, database management programs like dBASE III+ and dBASE IV and financial spread sheet programs Lotus 123 and Microsoft Excel. While these methods are certainly a step up in flexibility over a manual system, they still require a good deal of computer knowledge. To use these programs effectively, the rubber chemist has to learn how to program and write computer applications. Even after developing applications using these programs, most lack the flexibility and level of integration that rubber chemists need to manage their data effectively.

The Chemix compound management program was developed as a rubber compound management and documentation tool. It will operate on any IBM or 100% IBM compatible computer system with a minimum of 540K RAM and 2MB of available hard disk space. It is designed to meet the specific needs of the rubber chemist and to work intuitively by reflecting the methodology by which rubber chemists do their job.

Design approach and objectives

The program was developed and designed in accordance with the specifications of a number of leading rubber chemists, and it represents a modern design philosophy in that software should be intuitive and truly easy for first time computer users, without an extensive learning curve. It was written with the intent that rubber chemists should be devoting their time to doing what they do best - designing more cost effective formulations that can raise the manufacturers productivity and profits. To make the software program more accommodating to an end user without a strong computer background, we sought to develop a software program that would enable rubber chemists to create and modify formulae, enter raw materials, properties and test conditions and manipulate the formulation database to produce meaningful, informative reports, all in a matter of minutes.

Data management components

While actual data management requirements will certainly vary from organization to organization, there are a few central core elements that should be present in any compound management system in order to make it effective for use by a rubber chemist. Based on our discussions with rubber chemists, the following is a brief description of the major elements that should be present in any compound management system.

* Raw materials database. The fundamental starting point for managing recipe data is to create and set up a database of raw materials that are appropriate to the rubber chemist. In our program, we have created an initial, starting database with some of the most common raw materials used in rubber compounding, using a number coding system. In addition, the user may add an unlimited number of additional raw materials into the database. Since several raw materials may be interchangeable in mixing a formula, the program has allowed for multiple raw materials to be associated with a common raw material code. In this way, the rubber chemist can substitute "interchangeable" raw materials in order to evaluate alternative, more cost effective formulations.

* Suppliers database. In addition to tracking the raw materials associated with formulations, there is a need to maintain a database of suppliers so that purchasing decisions can be made. The suppliers database allows users to maintain an accurate, Up-to-date vendor database. Several different vendor contacts may be maintained for each company.

* Test conditions and physical properties. Test conditions are defined by the rubber chemist in an ASTM format as the conditions under which different properties are tested. A common example would be tensile strength. Physical properties at specific test conditions may also be connected to these test conditions and are brought into new formulations automatically, thus saving a tremendous amount of time and effort in creating new formulations. The program also maintains the minimum, maximum and average values of the physical test properties at specific test conditions.

* Formulations database. Directly connected to the

supplier, test conditions, physical properties, and raw materials files, the formulations database should allow the rubber chemist to flexibly choose from amongst available raw materials in building a recipe. In addition, the formulations data base must maintain records of raw material usage in terms of step and sequence, parts per hundred rubber (phr) and weights (in lbs. or kgs.) of each raw material to be used in the formulation. The program allows the rubber chemists to flexibly change raw materials and concentrations in developing experimental formulae, while maintaining the integrity of the database. In addition, the formulation database within the program also manages rubber mixing instructions and enables users to do conversions of unit measurements from lbs. to kgs. Figure 1 shows a typical formulation.

How the program is used The program is designed from the vantage point of the rubber chemist and is designed specifically to enable the rubber chemist to spend time concentrating on designing formulations and not writing software programs.

The process by which the software program is used on a daily basis is designed to mirror the actual process by which rubber chemists develop and make changes to their formulations in real life. The starting point is raw materials. As new raw materials are ordered, Chemix allows the rubber chemist to enter additional raw materials, as well as to update current inventory levels of existing raw materials. In addition, the program enables the user to track the sources of raw materials. The rubber chemist may add to the existing database of common rubber chemicals or may modify any of the raw materials already in the database. In addition, the rubber chemist may assign new raw material code numbers. Several, interchangeable raw materials may be grouped together under a common raw material code. The rubber chemist may create new codes so that alternative raw materials may be used to create lower cost formulae.

Once the initial raw material database is set up, the next logical step is for the rubber chemist to input common test conditions and their associated physical properties along with minimum, maximum and average values for those physical properties. Chemix features the ability to highlight the most common test conditions and then automatically bring in new test conditions and associated physical property values to each new formula created.

The recipe, or formulation section of the program is where the rubber chemist will spend most of the time actually using the program. The recipe section builds upon all of the data that has been previously entered. At the same time, a user can add to any of these files on-the-fly, fight in the middle of creating a recipe. The program is designed in such a way that it is easy to quickly scan existing recipes and to select out an individual recipe to update, as well as to create a new formulation. When creating a recipe, the rubber chemist can select out any combination of raw materials, test conditions and physical properties to be associated with the recipe. The program features the ability to substitute a raw material with an equivalent raw material and have that change reflect in all formulae. This is especially useful when the rubber chemist is sourcing alternative raw materials and wants to look at the impact changing the raw material on the composition and overall cost per pound of a formula.

Chemix goes beyond the recipe level. Mixing instructions for the production department can be generated, instructing the production department about the next batch to be mixed. The contents of a formula may also be "copied" to create a new formulation, which can then be manipulated. The system scans all existing formulations and prevents the user from overwriting an existing formulation, thus protecting the integrity of the database. This is a time savings feature that enables experimentation without compromising the integrity of the original formulation.

Proprietary formulations are the cornerstone of the chemist's competitive edge. The program provides for complete confidentiality of proprietary formulations through a password protection program that enables the system manager to assign specific fights to specific groups of users.

A flexible reporting system enables the rubber chemist to generate a number of reports, including a complete, accurate recipe book, a production report for the mixing process, a supplier list that indicates which raw materials are available from which suppliers, a materials usage report that shows which raw materials are being used in which formulations, and a formulae comparison report that shows a comparative analysis of up to five formulations and their associated recipes, physical property values and test conditions. The formulae comparison in figure 2 shows how the program can compare up to five formulae and their test conditions and properties, side by side.

The program also allows you to substitute a new raw material at a given step and sequence, as long as that raw material is associated with the same raw material code. Chemix allows the rubber chemist to analyze which raw materials are available from which specific suppliers.

References

1. Computerization: Improving your competitiveness in the global market, Rolland P. Schaar, PhD, Software Expertise, 308 Spring Creek Rd. Sagamore Hills, OH 44067. Rubber Division, ACS, Detroit, MI, October 17-20, 1989.

2. Integrated computerized system for recipe formulations, mixing and testing of materials in a rubber laboratory, Germ W. Visser, DSM Elastomers Europe, Research & Appl. Techn. Dept., P.O. Box 1130, NL-6160 BC Geleen, The Netherlands.

Dr. Sushil Bhatia is president of Simple Software International, Poughkeepsie, NY, specialists in developing simple to learn solutions for complex business environments. Jeremy Young is marketing director.