Extrusion International 6-2017

19 Extrusion International 6/2017 tricity and alignment. The material is then distributed in the proper location as part of the finished product. Understanding Maintenance Procedures It is important to get organized before you even start. Here are some examples: • Example 1 – In this example, with an improperly cen- tered tool, a calculated out-of-tolerance area of 0.059 in 2 . (38 mm 2 ) was derived. When the two surface areas were compared, the calculated material waste was 11.8 per- cent of the finished product. • Example 2 – Alternatively, if the percentage wall can be increased from 80 to 95 percent, a savings of about 12 percent of total cost can result. Savings will vary depend- ing on the designs, of course. Get help for heavy parts and awkward situations. Surfaces and edges are hard and therefore somewhat brittle, sodrop- ping a part or striking parts together can result in damage. Store your tools properly in a dry, clean area—a dedicated spot for each tool is best. These areas should have soft sur- faces and each instrument should be covered after cleaning. Also, tools should be segregated so that they do not come into contact with each other. And tools and all instruments should be cleaned thoroughly before storage. For disassem- bly of tools, it is imperative to use purpose-built tooling to fa- cilitatedisassembly. These shouldbe available fromyour sup- plier. If they are not, consult with a reputable tooling house for replacements. The cost of these tools is easily offset by po- tential damages, frequently caused by improper equipment such as hammers and drifts. Follow the guidelines outlined in your operator’s manual. Individual tools may have specific recommendations, so contact your supplier if anything is un- clear. Your supplier understands that optimumperformance relies on proper care andmaintenance. Here are some useful tips: • Clean your equipment while it is still hot as the residue is easier to remove. It helps to remove and clean one piece of tooling at a time in order to maintain elevated tem- peratures. • When cleaning a dual compound crosshead, (plastic and rubber) clean the plastic tooling first; the rubber second. • Never use steel tools such as scrapers or screwdrivers be- cause these can scratch and mar the tooling. • Do not use open flames because this generates exces- sive heat especially in thin sections, which can affect hard- ness, concentricity and tolerances of components. Recommended cleaning tools and materials include: • Brass pliers to grip material and aid in pulling • Brass scrapers available in different widths for cleaning flat exposed surfaces • Brass bristle tube brushes that are available in diameters from 1/16” to 1” in 1 /16” increments (ideal for cleaning holes and recesses) • Brass rods—different diameter rods are good for push- ing material out of flow holes • Copper gauze for cleaning and polishing exposed round or conical surfaces • Copper knives for removing residue from recesses and other hard-to-reach areas. Also, polishing compound re- stores polished surfaces • Compressed air, which is more effective for releasing plastic, but also aids in rubber removal. Be careful not to force debris into recesses with compressed air • Cleaning solutions may be useful, so remember to use fresh, clean rags (used rags often have metal chips em- bedded in them, which may scratch polished surfaces) Fig. 2: Extrusion tools require a disassembly/ reassembly cart as shown here. This allows precise realignment and prevents costly collisions that damage the die sections and product integrity