Wire Harness
Wire and cable do not generally come with all the modifications needed for a specific application. For example your application could call for wire with inkjet printing for easy identification during installation and usage. Similarly you may want your wires dyed various colors for prompt circuit identification. This is where valueadded manufacturers take over.
Several manufacturers supply distributors wire harness manufacturers and OEMs with valueadded services for wire and cable products. A valueadded service indicates a customization on an order that goes beyond a basic or core service. In other words it benefits the end user by adding value to the standard service offered.
In the electrical wire and cable industry valueadded services include braiding cut and strip printing barcoding dyeing custom put ups striping and more. These services can be broken down into four main categories Identification Solutions Installation Solutions Labeling Solutions and Packaging Solutions.
Identification Solutions: Striping Dyeing and Printing
Striping and Dyeing
Manufacturers and distributors of electrical wire often add stripes or dye a base wire another color. These processes are multifunctional as they add value to the product differentiate the wire for circuit identification and help control inventory volumes of stocked material.
In order to dye a wire a speciallybuilt machine feeds the wire product through a system of pulleys. First the wire passes through a wiper a foam circle that encompasses the entire cable. The jacket of the wire absorbs a formulated dye that is present in the foam. After passing through the wiper the wire goes into a heat tower to cure and dry.
Striping which many manufacturers offer for extruded wire is performed in the same machine as dyeing. However for striping the wire does not pass through a foam wiper. Instead the wire passes through a striper head that spins around the wire before it goes into the dryer tower.
The produced stripes are either longitudinal or spiral. Postproduction striping usually generates a spiral stripe like that on a candy cane. Longitudinal stripes which run along the side of a wire are also available postproduction but are not as common as the spiral type. Contrasting stripes are generally used when more than ten circuits have to be identified.
Almost all insulations are able to be striped including PVC rubber silicone and PTFE. Similar to striping most PVC compounds can be dyed to individual specifications without encountering any problems. However some compounds that are CVcured or irradiated are not able to be dyed because they were originally designed to repel both petroleum and alkalinebased chemicals. The color will not soak into the insulation and is prone to flaking.
Printing
In addition to common striping and dyeing methods there are other ways of marking wire for identification. Many OEMs and harness manufacturers prefer using printed wire in their assembled products. Printed wire not only helps in the assembly of products but also benefits installers and users of the finished product.
One way of marking wire is with inkjet printing. Using a dot matrix printer a series of dots create characters on a wire. For example in the automotive industry a harness may be manufactured for turn signals. In this case the specific wire would be inkjet printed left front turn signal or tail lights. Each wire would be color coded in the harness and inkjet printed making it userfriendly and easily identifiable.
Another way of marking wire is hot stamping which entails a process similar to that of a typewriter. A charactershaped head strikes a colored tape causing the chosen character(s) to appear on the wire.
Installation Solutions: Twisting Braiding and Cut & Strip
Twisting
Many OEMs need paired wire in the manufacturing process. Grouping single or multiconductor cables into various configurations can cut installation time dramatically. It allows wires to lie together which in turn makes working with them easier.
In order to create paired wire a process known as twisting must occur. Twisting entwines multiple wires and arranges them tightly next to each other. Two three and even up to eight wires can be twisted together.
The process of putting wire ends into a drill and twisting the wire is one homegrown twisting method thats still practiced on the production floor. It will get the job done to some extent but it will not remove the natural twist in each wire. This means that if the wire is cut into small lengths it will not stay twisted together.
Another problem with this method is the wire acquires dirt and grit on the production floor. The dirt could transfer to the finished product which could then pose major problems. Twisting using a dedicated wire twisting machine is the only way to get a good lay to the wires.
Braiding
One process that helps add protection against abrasion in harsh environments is braiding. Braiding is a process in which small strands are woven together on top of a wire or cable for added protection. At the start of the process numerous spools also called Bobbins of very small gauge wire (3236 AWG) are inserted into a wire braiding machine.
The bobbins are each placed in a precise location within the machine and the ends of each bobbin are pulled to the top of the braiding machine. Next the bobbins are subjected to a spinning or circular weaving motion while a wire or cable is pulled up through the center of the bobbins. As the synchronized process commences a weave or braid is manufactured over the cable. Finally the finished product is drawn out of the braid machine onto a larger spool or payoff.
Cut & Strip
Having your wire cut and stripped saves time and money and prevents excessive waste. Lets say you need 1000 fourinch pieces of wire to install in printers that you manufacture. For each piece you need .5 inches of wire exposed on the ends. Instead of having your factory workers manually cut each piece off the reel and then remove the insulation from the ends have your valueadded manufacturer complete the process for you.
The cut and strip process starts at one end of a cut and strip machine where a reel is held in what is called a payoff. The machine operator enters the overall length and desired cut and strip measurements for the pieces. Next the wire is fed through a set of pressuresensitive wheels that hold the wire tautly.
Then the wire is passed through a pair of blades that strip the insulation as it can sense where the bare wire begins. The wire is then pulled to the end to make the length cut. Finally it is pulled backward slightly in order to make the final strip cut. The pieces of insulation cu