Five benefits of using fasteners on carrier tape to reduce production line waste

Jon Lawson

One of the main goals for production engineers in manufacturing through utilising lean principles is to drive up quality and reduce wastage from the value stream; this can be achieved either by process automation or eliminating a one or more steps in the process.

Reducing the number of process steps in assembly will create a more efficient process, saving time and associated costs.

Alternatively, automating a process step involves replacing a manual element with a system that provides a more predictable process that delivers consistent results over any length of time or number of steps.

Process automation increases throughput and reduces error rates by improving accuracy and eliminating handling errors as well as affording the opportunity to reduce labour costs.  However, process automation may require significant capital investment in new technology and equipment to see the full benefits.

Is there another way? What are the implications for integrating a downstream manual process into an upstream automated process?

A good example is the assembly of PCB boards which has been revolutionised with the advent of surface mount technology components and equipment.

These components (usually ICs, resistors, capacitors, LEDs, etc) are packaged onto reels and fed into automatic assembly machines that quickly and accurately place them on to the PCB before entering the reflow soldering process to permanently attach them to the board.

Historically, these boards then progress to other processes for more non-electronic components to be fitted to complete the assembly.  Additional components consisting of connectors and fasteners are used to connect a number of boards together or to mount to the chassis or case of the final build. Errors at this stage in the process would mean that the boards would need to scrapped or reworked.

What if the fasteners could be packaged to be compatible with the surface mounting process and then packaged on industry standard carrier tape so they could be used in the automatic PCB assembly point?

The key benefits of integrating the secondary component assembly into the main assembly process are:

* Reduction of scrappage due to the failure in the secondary installation process through incorrect manual positioning and alignment of components.

* Reduce ESD risk from manual handling for the secondary component installation.  Finished fully assembled boards can pass straight to conformal coating.

* Reduction in product handing time through only needing to load and unload the board once.

* Modern high speed assembly machines will reduce the overall assembly time as they are typically faster than human placement and soldering.

* Reduction in labour costs as only one operator is required to complete the primary and secondary installation processes.

Fastening innovator PennEngineering has developed a range of surface mount products to specifically mount, stack or space boards; attach other components to the board and even create right angle attachment points and repeatable access with the use of loose screws.

The ReelFast fasteners are installed in the same way as any other component placement and the installation takes place at the same time as other components before entering the reflow soldering chamber.   All of the fasteners have a solderable plating and where necessary, the fasteners can be provided with a polyimide patch affixed to the end to allow for vacuum pick-up.

The ReelFast product line includes:

* Type SMTSO steel nuts and spacers/standoffs and Type SMTSOB brass versions, with or without threads for board mounting, stacking, or spacing applications;

* Type SMTRA fasteners introducing re-usable threads at right angles for mounting board to chassis, chassis to board, or component to board;

* Newly introduced Type SMTPFLSM all-metal, spring-loaded captive panel screws 

* Type PSHP captive panel screws with colour plastic caps allow for subsequent access to assemblies without the use of loose screws or the risk of compromising thread integrity over time.

PEM ReelFast surface mount fasteners can be supplied in a range of unified or metric thread sizes and lengths. By switching to PEM ReelFast fasteners, companies can improve their efficiency and throughput but have also automated and eliminated a secondary installation process step.