PlasticWeld Systems, Inc. Technical Support/FAQ's

Induction heating is a process that uses radio frequency energy broadcast through a specially formed cylindrical coil to heat up metal objects that are placed inside the coil. The process is very controllable, precise and repeatable.

Radio frequency energy is broadcast through a specially designed coil that encircles a metal forming die. The forming die is heated with induction to a specific temperature as the catheter tubing is inserted into it. The plastic polymer of the tubing is softened and reformed into the shape of the forming die. After cooling, the formed tube is removed from the die.

Catheter Tipping: two styles of catheter tips can be formed. Closed tips, usually a spherical radius end, seal the tube’s lumen to provide a smooth external round end. Open tips, often with two or more angled external tapers, can be formed to provide a smooth transition from the ID to the OD of the tube.

Catheter Tube bonding: in specialized catheters, single and multiple lumen tubes are often joined to short sections of tubes made from a softer durometer plastic. These “soft tips” are permanently attached to the multi-lumen tubes and usually feature an open tip with a smooth transition from the soft tip OD to the catheter tube OD.

Balloons on various catheters and endotracheal products can be bonded to the catheter tube OD using induction heating. These welds are superior to solvent bonded balloon joints because the sharp edges of the balloon stems can be smoothed – to enhance patient comfort. Also, no solvent is needed, so specialized fume removal systems are not required. There are some limitations to balloon bonding, so be sure to check with PlasticWeld technical experts before starting any projects.

Endotracheal tubes often require smooth formed tips and smooth eyes in addition to bonded balloons. All three processes are perfectly suited for induction heating. Filter media can be welded to molded plastic housings. Polymeric tubes can be fastened to stainless steel cannula.

PlasticWeld has successfully installed systems utilizing tubes as small as 0.013” OD (1 french size) and as large as 0.780” (60 french size).

Some catheter forming equipment relies on continuously heated dies. Although they do a good job forming the plastic, the formed areas do not have the chance to cool below the polymer’s softening point before removal from the die. This allows the possibility of distortion either during the removal process or in subsequent handling.

Other catheter forming processes rely on radio frequency generators using vacuum tubes. The performance of these tubes starts to decay from the first use and continues until it cannot heat up the metal dies. This continuous performance decay should be of particular concern to medical device manufacturers who rely on validated processes for their critical products. PlasticWeld’s equipment utilizes state-of-the-art solid state electronics to generate and control the process. The process remains consistent for the life of the equipment.

PlasticWeld’s induction heaters feature a proprietary power supply with water-cooled induction coil. When combined with solid state electronics, PLC control, and our proprietary forming dies, you are assured of consistent, repeatable performance for each and every cycle.

Also, PlasticWeld’s induction heaters provide fast, in-process cooling so you are assured of a fully formed part that retains its shape. No special handling is required, so your manufacturing process is robust and the end quality of your product is the best possible.

Most conventional thermoplastic polymers can be formed on PlasticWeld’s equipment. PVC, PU, Polyamide, PEEK, PTFE and others have been successfully roduced.If you are not sure about a polymer’s ability to be formed by induction, send us a sample for a free trial.

Thermoset polymers do not form well using secondary processing technologies. These types of plastics feature high heat resistance, and due to their  molecular make up, and once produced, will only degrade with application of  further heat. If you are not sure about a polymer’s ability to be formed by  induction heating, send us a sample for a free trial.

PlasticWeld’s induction heaters feature a proprietary power supply with  water-cooled induction coil. Combined with solid state electronics and PLC  control, you are assured of consistent, repeatable performance from each and  every cycle.

Most other forming processes rely on  continuous heat dies. Although they do a good job forming the plastic, the  formed areas do not have the chance to cool below the polymer’s softening point  temperature before removal from the die. This allows the possibility of  distortion either during the removal process or subsequent handling.

Also, PlasticWeld’s induction  heaters provide fast, in-process cooling so you are assured of a fully formed part that retains its shape. No special handling is required, so your  manufacturing process is robust.

PlasticWeld’s equipment is designed  to have the smallest total footprint possible. Tooling is mounted directly on the machine and presented to the operator for maximum ease of use.

PlasticWeld offers free prototyping for most situations. We request you send us  enough raw materials and complete specifications so we can generate samples  that meet your expectations. Prototypes are generally completed within 2 weeks  after receipt of raw materials.

Due to the large number of variations and options available, we cannot provide  a “one-size-fits-all” machine price. Please contact PlasticWeld to discuss the  best strategy for your product and manufacturing concept.

Precision tooling is custom-developed to match the specific requirements of  each customer. Our lead times generally range from as little as 4 weeks to as  much as 16 weeks depending on the complexity of the tooling.

PlasticWeld provides a fully detailed process set-up sheet with all turn-key  systems sold. We ask that you provide sufficient raw materials for process  development. Approval samples will be sent prior to shipment of the completed  machine.

PlasticWeld provides an easy-to-read manual that describes the operation of the  machine, lists preventative maintenance procedures and includes copies of all  relevant electro-pneumatic schematics.

The following options can be added to most machines

• Multiple forming cavities
• Larger power supply
• Cooled die holders
• Air chillers for cooling system
• Programmable electric slides for movement
• Dual alternating system that allows the operator to switch back and forth between two different sets of tools
• Ethernet board – allows remote access and monitoring of the machine’s performance

Cycle time is dependent on the amount and type of polymer being formed. In  general, larger masses require more forming and cooling time. Through the  years, we’ve seen cycle times as short at 3 seconds and as long as 40 seconds.

Eye forming differs from punching in one important way. Formed eyes have  smooth, rounded edges that minimize tissue trauma, whereas punched eyes have  sharp edges.

Cycle time is dependent on the wall thickness of the tube and the polymer. In  general, thicker walls require more processing time. Through the years, we’ve  seen cycle times as short at 10 seconds and as long as 40 seconds.

Formed eyes have smooth, rounded edges that minimize tissue trauma, whereas  drilled or skived holes have sharp edges.

Yes, two tubes of the same or compatible polymers can be successfully joined  using induction heating. In specialized catheters, single and multiple lumen  tubes are often joined to short sections of tubes made from a softer durometer  plastic. These “soft tips” are permanently attached to the multi-lumen tubes  and usually feature an open tip with a smooth transition from the soft tip OD  to the catheter tube OD.

Yes, any type of wire (solid, braided, spiral wound, etc.) can be present in a  tube lumen without affecting the tube’s ability to be formed.

PlasticWeld Systems is a full-function machine shop with many years of  experience in customized plastic joining equipment. Film sealers and heaters,  tube coiling units, ultrasonic tooling, hot air heaters and film cutting  equipment are a few of the custom units designed and built during the past 16  years.
We would be happy to consult with  you on any projects involving plastic forming, welding or bonding.

Due to their solid state electronics and high quality tooling, preventative  maintenance on PlasticWeld equipment is minimal. Monitoring the water quality  of the coil chiller water and regular surface cleaning of the exterior surfaces  are all that’s recommended.