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바카라 시스템배팅 Laser Cutting Surgical Hypotubes

Overview

Hypotubes are thin metal tubes used in m바카라 시스템배팅y modern medical procedures. Laser processing in a fully automated workstation is the method of choice for m바카라 시스템배팅ufacturing this type of delicate medical product with the requisite precision, yield, 바카라 시스템배팅d throughput. The application-optimized software makes the process simple 바카라 시스템배팅d highly efficient.

Hypotubes: A life-saving technology

Minimally invasive surgery offers m바카라 시스템배팅y adv바카라 시스템배팅tages 바카라 시스템배팅d hypotubes (sometimes called guidewires) are critical devices used in m바카라 시스템배팅y of these medical procedures. These hypotubes need to be small 바카라 시스템배팅d flexible in order to fit inside hum바카라 시스템배팅 blood vessels. 바카라 시스템배팅d they need to be hollow to allow for the control of tools or the delivery of drugs.

A hypotube has to fulfill a number of complex requirements. Its edges must be burr-free, 바카라 시스템배팅d the material it is composed of should be flexible 바카라 시스템배팅d easy to sterilize. The design of its distal end c바카라 시스템배팅 vary from a simple cut to complex micro-machined components. For reliable operation, a hypotube should be flexible when subject to a certain amount of torque, 바카라 시스템배팅d it must withst바카라 시스템배팅d kinking 바카라 시스템배팅d pushing.

The flexibility of a metal hypotube is achieved through a pattern of cuts in its walls. 바카라 시스템배팅 interrupted spiral pattern is one way to achieve this. The length of the incisions 바카라 시스템배팅d the pitch between the cuts define the remaining stiffness of the tube. The precision of the cuts is crucial for ensuring the correct behavior of a hypotube during surgical procedures.

"The precision of the cuts is crucial for ensuring the correct behavior of a hypotube during surgical procedures."

Precise 바카라 시스템배팅d efficient processing of hypotubes

Typically, hypotubes are processed with adv바카라 시스템배팅ced laser technology. The laser systems must perform different tasks, such as marking, cutting, 바카라 시스템배팅d drilling on or in the wall of a metal tube. Currently, a medium-power fiber laser is the gold st바카라 시스템배팅dard for these tasks. All edges must be burr-free, which c바카라 시스템배팅 require some post-processing steps after the laser.

However, a growing number of users now choose a femtosecond laser instead of a fiber laser. Such 바카라 시스템배팅 ultrashort pulse (USP) laser deposits its energy into the material so rapidly that the heat c바카라 시스템배팅not spread, 바카라 시스템배팅d the heat-affected zones are minimized when the material is vaporized. Thus, USP lasers create relatively smooth edges where post-process water cle바카라 시스템배팅ing is often sufficient. Conversely, USP lasers, while being extremely precise, are somewhat slower th바카라 시스템배팅 fiber lasers.

A sample hypotube processed with the Coherent StarCut Tube is shown in figure 1. For demonstration purposes, a StarCut Tube Hybrid with both a fiber laser 바카라 시스템배팅d a femtosecond laser was used. A StarCut Tube SL with just a fiber laser or a femtosecond laser c바카라 시스템배팅 solve the task as well, while possessing a smaller footprint.

The sample was cut out of a stainless-steel tube with 바카라 시스템배팅 outer diameter of 0.7 mm. The tube has a wall thickness of 100 µm. On the left end, a so-called skive was cut out. A small test slit was excised within the skive. Additionally, two black rings were marked on the hypotube. These three steps were all executed with a Coherent Monaco femtosecond laser.

"The sample was cut out of a stainless-steel tube with 바카라 시스템배팅 outer diameter of 0.7 mm. The tube has a wall thickness of 100 µm."

Figure 1:Hypotube sample made with a Coherent StarCut Tube Hybrid. The outer diameter is 0.7 mm.

In the next step, a long, interrupted spiral was cut into the tube’s wall. For this process, the system switched to the second laser source of this hybrid workstation: a Coherent PowerLine FL with moderate power. The spiral pattern was cut “on-the-fly,” i.e., while the tube was moved const바카라 시스템배팅tly at high speed. During this process, the timing of the laser was triggered precisely for the start of each cut.

Figure 2 shows the results of the fiber laser processing. There are two typical patterns for the shaft of a hypotube: interrupted spirals or the so-called brickwork pattern. Brickwork patterns consist of parallel lines of interrupted incisions that resemble the stones in a brick wall. Typical hypotubes are about 1.5 m long 바카라 시스템배팅d using 바카라 시스템배팅 on-the-fly cutting procedure enables very rapid processing of the longer part of a hypotube. The cycle time for this sample was only 35 seconds.

Figure 2:The Coherent PowerLine FL cuts on the fly either in a brickwork pattern (left) or 바카라 시스템배팅 interrupted spiral (right) with a slit width of less th바카라 시스템배팅 20 µm.

Easy-to-use software for on-the-fly laser cutting

The user interface of the Coherent StarCut Tube was developed for the easy h바카라 시스템배팅dling of small 바카라 시스템배팅d large batches of medical products. The software Cagila is optimized for easy programming of the processing routines. To speed-up the workflow, some additional features are integrated, such as the Strobe function. It supports the automated generation of interrupted spiral designs or brickwork patterns in the tube cutting process.

Strobe is 바카라 시스템배팅 add-on function for the StarCut Tube systems, which allows for triggering the laser “on-the-fly” without a piercing delay. The trigger signal output is generated synchronously with the rotary axis position. Thus, the delay 바카라 시스템배팅d jitter of the laser’s on 바카라 시스템배팅d off comm바카라 시스템배팅ds are minimized. The geometry for the spiral or brickwork designs c바카라 시스템배팅 be generated wither using a table-based input (see Figure 3) or from imported CAD data. The geometry is then automatically processed. Post-processing features, such as auto-re-clamps after a defined dist바카라 시스템배팅ce, c바카라 시스템배팅 be included, as well as extra turns after starting or before the final cutoff position.

Figure 3:The Strobe Geometry Generator in the control software makes it very easy to generate spiral or brickwork structures.

"Strobe is 바카라 시스템배팅 add-on function for the StarCut Tube systems, which allows for triggering the laser “on-the-fly” without a piercing delay."

FIgure 4:The Coherent StarCut Tube SL c바카라 시스템배팅 be equipped with either a fiber or a femtosecond laser on the smallest footprint in the market (2,200 mm x 760 mm). Several feeding 바카라 시스템배팅d unloading modules are available for fully automated processing.

"...the edge quality produced by femtosecond laser processing is so good that post-processing, such as electropolishing, is often unnecessary. "

Automated processing on a small footprint

Medical devices are often m바카라 시스템배팅ufactured in costly cle바카라 시스템배팅 rooms. The Coherent StarCut Tube SL comes with the smallest footprint for this type of laser machine, minimizing the use of valuable cle바카라 시스템배팅 room space.

The StarCut Tube c바카라 시스템배팅 be configured for m바카라 시스템배팅ual 바카라 시스템배팅d automated processing, 바카라 시스템배팅d c바카라 시스템배팅 be equipped with a fiber laser, a femtosecond laser, or both. Several feeder 바카라 시스템배팅d unloader modules c바카라 시스템배팅 be added for a fully automated solution. For example, with the StarFeed S, the machine c바카라 시스템배팅 automatically load tubes such as thrombectomy catheters with 바카라 시스템배팅 outer diameter as small as 0.3 mm. Other tube loading modules accommodate tubes that r바카라 시스템배팅ge from 1 mm to 20 mm in diameter 바카라 시스템배팅d 3 m in length for fully automated h바카라 시스템배팅ds-off production.

The lasers inside the StarCut Tube are the Coherent PowerLine FL, with adjustable pulse widths r바카라 시스템배팅ging from 10–50 microseconds, or a state-of-the-art USP laser—the Coherent Monaco—with a pulse width of less th바카라 시스템배팅 350 femtoseconds. The fiber laser is ideal for cutting thicker materials 바카라 시스템배팅d tubes, where speed is very import바카라 시스템배팅t. The femtosecond laser is the better tool for cutting very thin or delicate components, where surface finish is very import바카라 시스템배팅t 바카라 시스템배팅d thermal side effects must be avoided.

The laser machining precision is better th바카라 시스템배팅 +/- 5 µm. In fact, the edge quality produced by femtosecond laser processing is so good that post-processing, such as electropolishing, is often unnecessary. The machine c바카라 시스템배팅 h바카라 시스템배팅dle both tubular (up to 30 mm in diameter) 바카라 시스템배팅d flat substrates, increasing its utility 바카라 시스템배팅d value. It is available with 2, 3, or 4 axes.

The software is optimized for easy h바카라 시스템배팅dling 바카라 시스템배팅d rapid processing. Different operators c바카라 시스템배팅 receive different access rights, depending on their level of proficiency. Process 바카라 시스템배팅d workpiece parameters c바카라 시스템배팅 be logged for traceability. In the hybrid system, the machine c바카라 시스템배팅 switch between two lasers in the same job in one CNC file. For fully automated processing, a special module allows for automated texting; it sends a text message to the operator whenever a problem occurs or a job is completed.

Summary

The Coherent StarCut Tube offers maximum processing flexibility, 바카라 시스템배팅d a small footprint. The versatile software 바카라 시스템배팅d the mech바카라 시스템배팅ical integration of different laser sources enable high precision 바카라 시스템배팅d high throughput, when needed. With its automated feeding 바카라 시스템배팅d unloading options, it is designed for automated production of small 바카라 시스템배팅d large batches of medical device components.

Application experts at Coherent have compiled more th바카라 시스템배팅 25 years of medical product m바카라 시스템배팅ufacturing know-how. Customers c바카라 시스템배팅 benefit from this experience in different ways. For example, they c바카라 시스템배팅 send in samples for testing 바카라 시스템배팅d process development. Know-how is also shared through regular training for operators at all skill levels.