A TUTORIAL FOR PURCHASING FIREWORKS WIRE

FOR ELECTRICAL DETONATION OF FIREWORKS

MAJOR INGREDIENTS

BARE COPPER WIRE- Soft drawn ASTM B-1 specifications cover the most widely used copper wire for fireworks wire applications.

PVC INSULATIONS- Polyvinylchloride plastic materials commonly known as PVC make excellent abrasive resistant wire insulations and have good electrical characteristics. Pure virgin vinyl, rated at 60 degrees centigrade, should be the minimum offered. Reground, reprocessed PVC scrap insulations should never be accepted for fireworks wire applications. These scrap vinyl materials tend to allow a condition where pin holes develop along the insulated surfaces creating an unsafe field environment, particularly where wet conditions are evident.

THE WIRE EXTRUSION PROCESS

Top quality wire extrusion processing is an art. If the best grade of materials are specified, the only other major underlying factors necessary for superior quality wire products are; tooling and experience.

TOOLING- Tools needed for perfect insulated wire extrusion are costly and they do not last very long. A set of tools consisting of an extrusion tip and mating die have a duration of only several months of continuous operation and must be replaced or the end product will not be acceptable to Seminole standards.

EXPERIENCE- Our extrusion operators have processed trillions of feet with a zero field rejection record. By knowing about when tools start to wear and replacement sets are introduced they eliminate costly scrap and continue to produce the pyrotechnic industry most acclaimed fireworks wire products.

Inline extrusion spark testers set at 3,500 volts ac on ultra high frequency sine wave, state-of-the-art instrumentation devices, set off alarms as any thin wall or pin hole insulation is passed by the test area at high speeds. A 3,500 volt spark test is over eleven and a half times the rated voltage of the intended use.

Curing water temperatures must be continually adjusted to make sure the hot insulating material "set" correctly and are not too soft or too hard.

TESTING AND INSPECTIONS

Again, if the best materials available, best tooling and experience are evident, they do not mean a thing if proper testing, inspections and evaluations are not applied.

SINGLE WIRE CONSTRUCTIONS- Single wire is relatively easier to manufacture than twin or duplex wire types. We incorporate three distinct inspection and test procedures with our entire product line. (1) Incoming inspection for size of conductors as well as conformity of PVC compound, (received in prill form) as to texture, hardness and size. (2) Inline extrusion inspection for insulation stability, voltage resistance and concentricity to assure the conductor is uniformly formed in the center of the insulation. (3) Final test and evaluation for size, weight, concentricity and continuity both visually and with instrumentation.

DUPLEX WIRE CONSTRUCTIONS- With duplex or twin lead wires, inspections and testing involve further steps. Both conductors must be concentric within the insulation plus the thin web of insulation separating each wire must be secure enough to hold together yet light enough to allow the wires to separate with ease. Our patented "Red-Line duplex" with a red colored polarity marker on one wire affords the technician positive circuit identification.

SPOOLING- Fireworks wire are packaged on plastic spools and are available on standard lengths of 500 and 1000 ft spools. Of course we convert to metric equivalents for our international trade.

Although Seminole has standardized spool sizes our manufacturing facility allows packaging of larger plywood reels, packaging up to twenty thousand feet, depending upon the customers request.