What is staking?
Plastic staking is a method of joining components together that uses a molded stud or boss to mechanically retain a mating component. Heat is applied to the boss, softening it. A forming tool is then used to reshape the material into a cap or stake.
There are many types of plastic staking technologies. They vary in their application of heat and pressure, but the general concept is the same, form a plastic boss or stud into a stake to retain a mating component. Here are a few of the different staking technologies available.
nanoSTAKE
Revolutionary staking process that uses Smart Respond™ heating technology to rapidly heat and cool a punch to stake plastic.
InfraStake
Focused infrared light radially heats the plastic boss and a non-heated punch forms the stake.
Hot Air Cold Punch
Heated air softens the plastic boss and a non-heated punch forms the stake.
Ultrasonic
Metal tool (sonotrode) vibrates against the plastic boss generating frictional heat to melt it and form a stake.
Thermal Punch
Heated metal forming tool melts and forms the plastic boss into a stake.
The InfraStake Process
Clamp
Module is positioned over the molded boss. The face of the concentrator clamps the part directly at the stake point.
Heat
Infrared (IR) lamp is illuminated. Light is focused radially on the plastic boss.
Form
IR lamp is switched off and the non-heated punch forms the semi-molten boss into a stake.
Retract
After the plastic has re-solidified, the punch retracts and the module retracts from the part.
Read our blog posts about InfraStake.
How to determine the strength of a plastic staking joint
Design engineers often ask us, “How strong will my staked joint be?” Usually, they’re designing a plastic assembly that needs to be staked, and they need to know how to design the part.
Service beyond the machine
Mark recalled seeing a demo of Extol’s InfraStake technology a few months prior and was drawn to InfraStake’s built-in clamping feature that ensures tight stakes. Mark was hopeful that InfraStake would be a good fit for the door panel line, but wanted confirmation that the technology could meet the cycle time, strength, and assembly tightness requirements. That’s when our Applications Lab, the first of Extol’s wide array of customer-supporting service groups, stepped in to help.
Why you see flash when staking plastic and how to optimize it
The moment is here, the process is set, the machine has cycled. How does it look? “GASP!” My staked part has FLASH!!! If you are not familiar with flash, I’m referring to the displaced plastic material from a staking or welding process that extrudes outwards and does not contribute to the strength of the joint. Flash may be observed as fine dust surrounding the joint, thin strands of plastic material in a disorganized clump, or even smooth rounded material adjacent to the weld joint. So why does flash occur in plastic staking and how can you optimize stake appearance?
Learn more about InfraStake.
The nanoSTAKE Process
Heat
The Smart Respond™ heating technology heats the punch to a programmed melt temperature in seconds.
Form
The low-current, high-performance heater maintains melt temperature as the punch forms the boss into a stake.
Cool
Once the punch reaches the correct height, it rapidly cools to a programmed release temperature.
Retract
The cooled module retracts with no sticking.
Read our blog posts about nanoSTAKE.
Staking tightly spaced plastic bosses
Staking tightly spaced plastic bosses together is easy with nanoSTAKE. Extol’s grouped configurations make it possible.
A grouped configuration combines up to 6 modules on one actuator so that each individual nanoSTAKE point can be spaced closer together. In this configuration, nanoSTAKE modules move together as a group and share the same measurement from a common position sensor.
Extol receives patent for revolutionary nanoSTAKE® plastic staking technology
Extol is pleased to announce that we have received a patent for our revolutionary nanoSTAKE plastic staking technology. This is Extol’s second patent for a staking technology that will change the manufacturing industry. NanoSTAKE was developed to.
How to determine the strength of a plastic staking joint
Design engineers often ask us, “How strong will my staked joint be?” Usually, they’re designing a plastic assembly that needs to be staked, and they need to know how to design the part.
Learn more about nanoSTAKE.
The Hot Air Cold Punch Process
Heat
Air passes through a heater and is directed at the boss.
Form
Hot air shuts off and a non-heated forming tool forms the semi-molten boss into a stake. Cooling air passes through the module to cool the stake.
Retract
After the plastic has re-solidified, the forming tool retracts.
The Ultrasonic Staking Process
Heat
A metal tool (sonotrode) vibrates against the boss generating frictional heat.
Form
As the plastic melts, the sonotrode forms the boss into a stake.
Cool
Vibration stops and the sonotrode continues to apply pressure to the stake while it cools.
Retract
After the plastic has re-solidified, the sonotrode retracts.
The Thermal Punch Process
Heat
A hot metal forming tool applies pressure and conducts heat into the boss.
Form
As the plastic melts the hot tool forms the boss into a stake.
Cool
Cooling air is directed at the forming tool, lowering its temperature.
Retract
After the plastic has re-solidified, the forming tool retracts.
Ready to get started?
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