Archive for March 2015

Methods of Marking Wire and Cable

Marking wire with an identifying number or character has been a necessary part of wire assembly for as long as anyone can recall. Most electrical standards require a mark identifying a specific electrical circuit for tracability in assembly and service

Methods of marking a wire continue to evolve as processing technology improves. New methods are being introduced to compliment existing processing methods which continue to be effective. The result is a wide range of processing options to meet virtually all applications and production volumes.

We will outline some of the more common processing methods and how they are applied in a production environment.

Labels

Label mark

Adhesive labels are an effective method of applying an alpha numeric mark to wire. Processing methods include manual from a box or card, labeling guns and semi automatic systems.  Label adhesion can be affected by the type of wire insulation and quality of the label itself.  Permanence can be affected by the above plus the operating environment of the wire. The operating environment can include temperature, humidity and the presence of chemicals or contaminants). Cost of application equipment can range from zero (manual) to high (semi-automated, integrated with a cut only or wire cut and strip machine).

Hot Stamp

Stamprite Machine Hot Stamp Marker

Hot stamp marking is a wire marking process that dates back to World War II.  Hot Stamp marking uses heat type and thermal marking foil to place a mark to the surface of a wire.  The wire is fed through a guide or anvil and the guide assembly lifts up to contact the heated type surface with the foil sandwiched between the type and the wire.  There are two types of hot stamp markers, separate marking type and wheels.  The separate marking type are arranged in the desired number sequence and mounted into a type holder.  In the case of a wheel type of marker, each wheel represents one character and includes the characters generally used (0-9, A-Z, blank and special marks: right and left arrow and hyphen).   Wheel type are quicker to change over and lend themselves better to manual or automatic processing. Actuation is by lever or foot pedal for manual (offline) processing and integrated into a semi or fully automated solution with actuation controlled by the automation system.

Hot stamp marking is less prone to environmental conditions that can affect the adhesion of a wire label.  Some industries specify other marking methods as the mark is imprinted to the surface of the wire using heat and there are concerns about potential damage to the insulation.  But the cycle time is limited and the heat applied is localized so this processing method is acceptable for the majority of applications.

End marking (same or different number on opposing ends of the wire) and continuous (along the length of the wire at a fixed distance) are normal processing types.  Continuous marking does slow down a semi or fully automated wire processing machine as the wire feed must stop during the stamping process.  The number of marks and distance between marks affects processing speed.

The type of thermal marking foil used, the temperature of the type and impression time are critical factors for a hot stamp mark.  The insulation type and wall thickness normally determine the foil, temperature and cycle time. Marking foil normally comes in rolls and is white or black.

Ink Jet

Ink Jet marking is a newer technology relative to hot stamp.  Ink droplets are sprayed onto the wire surface in a pattern to form a character or character string.  Ink jet marking systems are fully programmable and offer more character options than other methods.  These markers can also interface into the operating system of semi or fully automated processing systems. The interface provides programming and processing communication to the marker.  End or continuous marking is possible but It is important to note that without a programming interface between the processing machine and marker, only continuous marking can be processed.  Line speed is quicker than other processes as the process does stop to apply a mark to the wire.

There are a wide variety of pigmented and non-pigmeted inks available to suit a wide range of insulation types.  In addition, chemicals to clean the ink jet head are required to prevent dried ink from clogging the jets. Special handling of ink and chemicals is required and maintenance personnel are normally trained how to properly apply and store chemicals. Ink jet markers are typically dedicated to one type or ink due to the cleaning process required to transition from one ink type to another.

Permanence to an insulation can be a factor as the ink normally does not penetrate below the insulation surface.  The mark can rub off in some environments.  Using pre or post treatment methods such as plasma or UV curing can improve the adhesion of the ink to the wire.

Heat Shrink

Marking to heat shrink and applying the marked heat shrink to a wire is another method.  The heat shrink tube is marked and cut to length on a dedicated machine.  The marked heat shrink tube is applied to the wire manually using the Judco Focus Lite or heat gun.  The mark to the heat shrink is applied using methods such as hot stamp or ink jet.

Judco Focus Lite

Laser Marking

CLC Wire Mark

 

Laser marking is an emerging marking technology.  Line speed is slower than ink jet but suited for continuous marking.  Mark characters and character strings are programmable.  A black mark is the primary color as the character is burned into the insulation surface.  A marking method endorsed by military and aerospace.

Wire Process Specialties provides solutions for processing wire harnesses.  Connect Your Way to WPS to see how we can assist your company in their processing problems.

Methods of Processing Wire Assemblies.

Business conditions are more competitive than they ever have been.  Global sourcing has placed extra price pressure on companies. Competitors domestic and offshore are lobbying for business which was once secure. Profit margins are slim with little or no margin for error. Manufacturing in North America has unique challenges and those challenges are especially acute within the wire processing industry.

Regardless of the region a company is based, there is one common objective each company has.  That is finding the best processing solution that will optimize their production efficiency while lowering overall processing costs. And making the best use of people resources. The purpose of this article is to outline some of the processing types, offer examples of those processing types related to wire processing and guidelines for application.

Manual Processing Tools.

ae-header

Manual tools are the most basic of processing types.  One person and one tool process a single step in an assembly process.  Manual assembly is used in low volumes assembly, where access is restricted or where the tool needs to be brought to the work. Worker fatigue can be a factor in the use of manual tools.  This can affect overall output and quality as volumes increase. Excellent processing solutions for companies who process low volumes in a high value added production envirnoment.  Examples of manual tools include hand crimp tools, heat guns, wire strippers and wire cutters. High production flexibility with manual tools. Minimal set up and maintenance time. Acquisition cost is low.

Single Process Bench Tools.

FLG2

Single Process Bench Tools extend the manual process to a bench processing machine. One person and bench processing machine process a single step in an assembly process. Output is moderately higher than a manual process, but operator fatigue is much lower and quality is higher due to the power assist and repeatibility of these units.   High flexibility with single process bench tools, minimal to moderate set up time especially with newer motorized units.  Minimal maintenance time. Examples of single process bench tools include wire cutters, wire strippers, wire crimping (loose piece and reel mounted contacts) and heat shrink processing machines. Acquisition cost is low. Ultrasonic wire splicing and laser wire stripping are other example of a single process bench tool but the acquisition costs for these solutions are higher.

Multi-Process Bench Tools

97A

Multi-Process Bench Tools combine two or more processing steps into one machine type. One person and processing machine process a multiple step in an assembly process. Output is much higher than with more than one assembly machine processing the same steps. Processing time and labour content is lower than with manual or single processing bench tools. Set up and maintenance skills are higher while operator skills are moderately higher. Examples of multi-process bench tools are wire and tube measure to length and cut, wire measure to length cut and strip, coaxial wire strippers and terminal stripper-crimpers. Acquisition cost is moderate.

Wire Processing Automation

Megomat 2000

Automation combines many processes into a single automation system.  One operator monitoring output and unloading finished leads.  Output is generally designed for high volume global production.  Due to quick change press applicator bases and programmable motorized machine motions, set up is quick so lot sizes can be reasonably smaller.  Set up, operation and maintenance skills are high.  Examples of processes which are typically automated include terminal crimping, wire doubling (two of the same wires crimped to one terminal), wire twist flux and tin, ultrasonic wire tipping and weather seal insertion. Acquisition cost is high.

Installation, training and ongoing support

In all categories, proper training services are critical.  The first 30 to 60 days of an installation are important especially in the automation category as the business adapts to the new installation and personnel get used to the operation of the equipment.  A good supplier commits to ensuring the installation to operation period and beyond goes smoothly and they resolve routine questions or issues as they occur.

WireProcess Specialties supplies wire processing solutions from our Global Technology Partners Group.  We have over 3 decades of service to our valued customers. Connect Your Way to find our how WPS can support your processing requirements.