Thursday, December 15, 2011

Boost Performance, Speed, Economy with Servo-Controlled Ultrasonic Welding

Ultrasonic welding is one of the most widely used processes for bonding polymers, valued for its speed, flexibility, and low cost. In recent years, there has been greater demand from OEMs and processors for more controlled and consistent ultrasonic welding, especially for production of medical devices and high-value precision components. New developments in electric servo-driven welders are helping to meet this challenge.

Application testing and customer feedback have shown that electric servo-driven ultrasonic welders can provide significantly more consistent results than standard pneumatic ultrasonic welders. Servo-controlled welding is targeted for production of components and assemblies that require precise dimensional tolerances, such as those in medical, electrical, automotive, robotic, and fluid-control systems. Servo-controlled ultrasonics also facilitate production of parts that require FDA validation, where the process affords repeatability and precise documentation.

With servo systems, processors of high-value goods such as medical components have a servo-controlled welding option that brings significant performance benefits over pneumatics. This is a breakthrough development in plastic welding that solves manufacturers’ most pressing challenges: process repeatability, validation, calibration, and manufacturing cost.

Ultrasonic welding is the joining of thermoplastics through the use of heat generated from high-frequency mechanical motion. Although it was first developed several decades ago and has been widely used in the plastics industry for a number of years, there have been few fundamental design changes in the process since Dukane’s introduction of “Weld by Distance” in 1988.

Servo-controlled ultrasonic welders, like Dukane’s iQ
series with Melt-Match technology, offers numerous advantages over pneumatics, such as much
more precise control of weld and hold collapse distances.
Ultrasonic welders have long been a popular choice for joining thermoplastics in a broad range of end-use markets, due to several factors. The equipment is compact, easy to incorporate into automation, and economical. Additionally, ultrasonic welders can produce high-quality welds in a short cycle time. The greatest advantage of ultrasonic welding, however, is the ability to use very precise process control.

The welding equipment typically consists of a press, generator, transducer, booster, and horn. The generator converts standard electric line power into high-frequency AC voltage that is then passed through the transducer. The transducer consists of piezoelectric ceramics that expand and contract at the same frequency as the alternating voltage applied to each side of the ceramics. This sinusoidal mechanical vibration is then passed through the booster and horn into the parts to be joined. When force is applied between the parts by the press, these vibrations pass to the weld joint area, where melting occurs. After the vibrations are stopped, the plastic solidifies during the “hold” phase, forming a welded assembly.

The basic function of a pneumatic press is to apply force between the parts using an air cylinder. The amount of force is generally controlled using a pressure regulator and one or more valves. Typical process-control parameters available to the user are ultrasound amplitude, weld pressure (constant or profile), weld time, hold pressure (constant or profile), and hold time. More advanced systems also have the ability to measure distance, allowing a level of control of the weld and hold distances.

Servo-driven welders such as Dukane’s iQ Series, which was introduced in 2009, is different from pneumatic systems because it utilizes an electrical servo actuator in place of the pneumatic cylinder. Instead of controlling the force, the servo system controls the speed of the horn during the weld and hold phases. Typical servo process-control parameters are ultrasound amplitude, weld distance, weld speed (constant or profile), hold distance, hold speed, and static hold time.

The servo-driven welder provides several advantages over pneumatic systems. The main advantage is significantly more precise control of the weld and hold collapse distances, which stems from the underlying method of distance control. In pneumatic systems, the distance is controlled indirectly by relieving pressure from the air cylinder once the desired distance is achieved. Due to the limited rate at which compressed air can escape the cylinder, as well as other factors, the press typically travels beyond the desired collapse distance by varying amounts.

Conversely, the servo system controls the distance directly through closed-loop servo position control. The servo dynamically seeks to arrive at the desired position, yielding very precise and repeatable results.

Data from an experiment comparing repeatability of distance welding for round polycarbonate filter parts (see Fig. 1) indicate that the standard deviation of the total part collapse was more than 3.5 times smaller for the servo system than a pneumatic system (actual values were 0.00012 in. or 3 μm for the servo vs. 0.00046 in. or 12 μm for pneumatic). The standard deviation of the weld pull strength relative to the average was smaller, as well—2% for servo vs. 4% for pneumatic.

Fig. 1—Experimental data comparing repeatability of distance welding
for round polycarbonate filter parts show that the standard deviation
of the total part collapse was more than 3.5 times smaller for the servo
system than for a pneumatic system.
An example of servo performance in an industrial setting is the welding of the dual check-valve parts shown in Fig. 2 (parts and weld data come from Value Plastics Inc., Fort Collins, Colo.). When programmed to weld by collapse distance of 0.0088 in., the servo system achieved an average collapse of 0.0088 in. (224 μm) with a standard deviation of 0.00008 in. (2 μm) for a 1000-part sample. In addition to the highly repeatable weld collapse performance, the quality of the welds obtained on the servo system was better than with a pneumatic welder due to the elimination of air bubbles near the weld zone (Fig. 3).

Fig. 2—Another example of servo performance is the welding
of dual check-valve parts molded by Value Plastics Inc. When
programmed to weld by collapse distance of 0.0088 in.,the servo
system achieved an average collapse of 0.0088 in. (224 μm)  with
a standard deviation of 0.00008 in. (2 μm) for a 1000-part sample.

Fig. 3—The quality of the welds obtained on the servo
system beat that of a pneumatic welder due to the
elimination of air bubbles near the weld zone.
Another advantage is the ability of the servo press system to change speed rapidly. In certain applications, it is desirable to profile the speed during the weld in order to match the rate of material melting. Since most ultrasonic welds take less than 0.5 sec, it is critical to change speed quickly to achieve meaningful weld profiling. The servo system is capable of accelerations of 50 in./sec2, which is equivalent to changing speed by 1 in./sec in 0.020 sec.

The ability to program independent speeds for up to 10 different segments of the weld, along with the servo system’s ability to dynamically sense when melting is initiated at the beginning of the weld process, is what Dukane terms Melt-Match technology. Although some pneumatic systems are capable of varying the force during the weld, the rate of change is restricted by the time required to move air in or out of the air cylinder. Rapid speed changes on the servo welder also afford the flexibility to achieve hold speeds that are substantially different from the weld speeds.

Versatility is another key advantage of servo systems. Some applications considered very difficult if not impossible to achieve on a pneumatic welder, have been successfully executed on a servo system. One example is sealing and cutting of thin films, where the weld distances and forces are quite small. With precise distance control, the servo system is capable of achieving quality welds.

Other advantages of the servo system include:
  • Enhanced control capability in the hold phase, which consists of a dynamic stage (parts are collapsed further after ultrasound is turned off) and static stage (servo maintains its final position to allow the solidification process to complete).
  • Ease of calibration due to the elimination of pneumatic components.
  • Ease of welder “cloning” due to digital process control (i.e., ability to set up multiple welders to achieve identical performance).
Servo-controlled welding systems also provide many cost benefits. Due to the high degree of process repeatability, rejects can be reduced. This enhanced ability to maximize yields is especially important in cases where the assembled parts are of high value.

The elimination of compressed air for press actuation can also produce savings. A typical 40-hp compressor can cost approximately $13,000/yr to operate. In addition, the expected maintenance costs are smaller. In typical applications, the servo actuator has a life span in excess of 200 million cycles.

To ensure process repeatability and maintain calibration, the servo system is designed without adjustable mechanical operator controls on the machine. This prevents accidental or unauthorized changes in calibration and validation.

Another key feature that provides tighter process control is Dukane’s patented iQ series power supply. It boasts industry-leading processing speeds of 0.5 millisec. The system also uses iQ Explorer graphical user-interface software for facilitating process setup and weld-data acquisition.

While servo systems are generally more expensive than standard pneumatics without process-control capabilities, they are within the price range of high-end pneumatics with advanced control features. Dukane’s servo-controlled systems have been installed at multiple OEM and processor sites in North America, Europe, and Asia.

About the Author
Paul Golko is senior project engineer at Dukane Corp., St. Charles, Ill., where he has worked on the development of servo-driven welding equipment, including the iQ servo ultrasonic welder.

Friday, September 23, 2011

A Primer to Spin Welding

By Jerry Wibben, Regional Sales Manager, Dukane Corporation

Spin welding is a simple process that has been around (pun intended) longer than thermoplastics. Spin welding of metals has been known and practiced for at least a hundred years. It is no surprise, then, that it is one of the oldest methods of joining thermoplastic parts. It is a fast way to join parts that have a circular joint, and is very reliable at delivering a hermetic seal in those products that require one.

The fundamental idea is to spin one part against another under clamp force, the surface friction creating heat that melts the interface, and then to stop rotation and allow the parts to fuse together. It is a process that is deceptively difficult while in truth, as with many materials, it really is quite simple.

The Phases of Spin Welding

The phases of a spin weld are the approach, weld, hold, and retract. There are several ways to begin the rotation. If the part is to be rotated by frictional contact with the spin tool (as opposed to engaging a detail such as drive dogs or hose barbs), the tool can be spinning before contact. Alternatively, the tool can approach not spinning, pick the part up either with friction or vacuum, retract slightly, start spinning, and then extend again; or the tool can apply pressure prior to spinning. Of course, the part also can be directly loaded into the spin tool and held in place by friction or vacuum.

During the spinning portion of the cycle, the first thing that happens is some small amount of heat build-up that softens but does not melt the surface. When this happens, material will be stripped from the surface and rolled up into little balls. This is why spin welding produces particulate. As spinning continues, heat continues to build. Once sufficient heat has built up, true melting of material will occur. At this point, bond line thickness is established; in other words, additional spinning will not add to bond line thickness or strength of the part. Additional spinning, however, will cause the parts to travel toward each other with excess melted material thrown out of the joint in the form of flash and particulate. Concealing this flash and particulate is an important part of designing the joint.

Once true melting is established, rotation can be stopped. It is important to maintain clamp force on the parts and to stop the rotation as abruptly as possible. If spin down occurs in a gradual fashion, the material can start to solidify before rotation stops and the joint interface can be severely weakened by shear forces applied during this cooling period.

Virtually all thermoplastic material can be spin welded if they have a high enough ratio of the coefficient of friction to thermal conductivity. To put is more simply, heat needs to be created faster than it can dissipate. Usually, only materials with very high lubricity are excluded from consideration. Care should be taken to ensure that materials on both sides of the joint are not only chemically compatible, but have similar melt temperatures and similar melt flow indices. If materials are reinforced (i.e. with glass), there will be no benefit of reinforcement in the joint itself; the spin welding process does not promote any fibers crossing the joint line, rather it encourages fibers to lay parallel to it.

The joint itself needs to be a circle, but the remaining part geometry is fair game, as long as it does not interfere with rotation or create a severely out-of-balance condition for the rotating part. This is particularly a concern for small parts, as the rotation speeds may need to be high.

Rotation speed is based on the surface speed at the joint, so smaller parts turn at a higher rate than larger parts. A rule of thumb is that the target rotation speed in rotations per minute should be about 8,000 divided by the joint diameter in inches, or 200,000 divided by the joint diameter in millimeters. This is a ballpark speed, with successful applications running at speed deviating from this rule by 50 percent or more both high and low.

Three Main Classes of Spin Welders

Inertial spin welders typically use an air motor to spin up a flywheel, which can be clutched in, but is more commonly attached to the tool in a fixed manner and engages the part frictionally. The part acts as a brake for the flywheel; so the kinetic energy stored (mass of the flywheel multiplied by the rotational speed) is the energy imparted to the joint. Because of the high speeds air motors can generate, these machines work well for very small parts, and they are simple and reliable. They can, however, be hard to adjust and hard to convert from one job to another. These machines also cannot control radial orientation of the finished part.

Conventional electric direct drive or geared spin welders use AC induction motors to drive the spin tool. They generally use digital motor controllers so rotational speed can be adjusted. Many also have electronic dynamic braking. In situations where dynamic braking is not sufficient, a physical brake may be installed. These machines can be built to any speed or torque requirement, but high torque motors tend to have heavy armatures so they do not stop quickly if turned at high speeds. Induction motors also delivery their highest torque only at high speed; so gearing is often used n high-torque applications (large parts, low rotation speeds) to keep the motor shaft speed up in the high torque part of the power curve. While certain of these machines do have sophisticated controls, many are quite simple. These systems also are not capable of controlling the radial orientation of the finished part.

Servo driven spin welders, whether geared or direct drive, typically can control the finished part radial orientation to within one degree or better – a specification that usually depends more on the tooling than the machine. Servomotors have relatively flat torque curves all the way from a near-standstill to maximum rated speed, so they typically are more versatile than the other types of machines. A servomotor also is typically more compact for a given torque rating than an induction motor, and is much better at staying on speed under load. Machines using servomotors usually have more sophisticated controls and a variety of welding methods. Servomotors also can deliver feedback to the control, so torque ad energy can be monitored during the process. Gearing, if used, is almost exclusively intended to multiply torque rather than simply to change the output speed. These systems are typically very precise and repeatable productions tools.

Spin welding is a simple process that, when coupled with modern servo motor technology, delivers precision and repeatability beyond that dreamed of when it was first tried during the open-cockpit days of the plastics industry. The process is fast and stable, and will continue to be utilized for as long as making products out of thermoplastics maintains its popularity.

Thursday, July 28, 2011

What Amplitude is needed to weld my plastic components?

What exactly is “Amplitude” and why is it important?  Amplitude is the peak-to-peak movement, or expansion/contraction, of an ultrasonic tool stack.  Each component can multiply the amplitude that comes from the transducer, the amount of increase or decrease is called "Gain".  The total gain of the stack components determines the final amplitude at the working face of the ultrasonic horn, where part contact is made.  The ultrasonic tooling stack includes the transducer, booster and horn.  Some applications do not require a booster and the horn is attached directly to the transducer.   These are usually multi-head automotive applications or packaging applications.

Some customers have tried to save money by not purchasing the correct booster for their particular application.  Making sure the ultrasonic tooling stack is producing enough amplitude is one of the most important factors to successfully welding parts. 

Yes, there may be a setting or two that can be adjusted in the ultrasonic welding system, like adjusting the pressure, but that doesn’t mean that the material at the joint area is actually co-mingling.  If parts are not welded properly, they probably won't pass inspection or may even break apart in your hands.  Worse yet is the possibility of your customer returning parts due to poor quality.  Insufficient amplitude is often evidenced by not only weak welds but also incomplete welding where the melt around the interface is not completely present.  A weld detail, e.g., energy director, may show signs of embedding into the mating surface instead of melting.  If you have a weld time that is less than .1 seconds and your process seems to produce erratic results, then possibly your amplitude is too high and a reduction needs to be made.

A chart is included that shows some amplitude requirements of basic materials.  Use the example as a guide for your current resin and ultrasonic tooling stack to see if you have enough amplitude for your application. Generally speaking, amorphous plastics require less amplitude than semi-crystalline materials.  

Click to enlarge
Dukane’s application engineers can assist you in calculating the proper amplitude for your ultrasonic welding application and quote the proper booster to match up with the horn.

Monday, July 18, 2011

Dukane IAS receives Illinois Export Excellence Award

Dukane Corporation’s Intelligent Assembly Solutions (IAS) Division was recognized by the State of Illinois for the significant growth that has occurred in our export sales in recent years. As part of Illinois annual “EXPORT WEEK”, thousands of Illinois based companies who are involved in exporting, are invited to apply for the annual recognition given by the Governor of Illinois to Exporters. Companies can apply for recognition of their efforts as either a new exporter if they have less than three years of export experience, or as an experienced exporter if they have more than 3 years of export experience. Within each company size segment, a board of judges reviews the applications and then select 3 companies. One is given an award as the best “New Exporter”, one is given and award for best “Continued Excellence in Exporting”, and one is given “Best Exporter”. The award is given based upon a number of criteria which include overall growth in export sales in recent years, and the amount of employment related to those export sales. Dukane was recognized as the 2011 Continued Export Excellence Award winner for the mid-size company category. The awards were presented on June 21 by Illinois’ Governor Quinn at the annual Export Week Conference which was held at the Illinois Institute of Technology.

In addition to the awards, there was a conference which included presentations by several of the this year’s award winners. Dukane was represented on the panel by Russ Witthoff, Director of International Sales.

Friday, April 29, 2011

Novel Combination Locking Cap for Prescription Drugs

New plastic locking cap uses Dukane's ultrasonic welding systems for speed, accuracy, and precision manufacturing

Cap-N-Lock LLC, Lincoln, Calif., has developed the industry’s first combination locking cap offering maximum security against unauthorized use of prescription medications. The plastic locking cap is claimed to be the safest child-proof cap, provides maximum protection against teen prescription use, and is a senior-friendly packaging option. The device uses precision ultrasonic welding technology from Dukane Corporation's Intelligent Assembly Solutions (IAS) Division for speed, accuracy, and precision manufacturing.  At the February 2011 Medical Design and Manufacturing West show Dukane demonstrated welding the cap on its new iQ servo welder in its Lean Manufacturing Cell (shown below).

iQ Lean Manufacturing Cell

The locking cap has combination dials which create a barrier to entry for young children and teens, according to Joseph Simpson, president of Cap-N-Lock LLC. The company produces the cap and two adapters which fit a wide range of the most common prescription bottles. The locking cap components, molded by Henry Plastics, Fremont, Calif., consist of eight injection molded parts made of lightweight, strong acrylonitrile-butadiene-styrene (ABS) plastic. Assembly and manufacturing is done by Cap-N-Lock LLC.

Locking Cap

The locking cap unit is assembled from the bottom up with the locking mechanism (dial numbers included) dropped in first, followed by a tension plate and then the lower twist-on cap. The lower housing ring is then ultrasonically welded to the main housing to complete the assembly.

The speed, accuracy, and precision of the ultrasonic welding process are critical in the production of the locking cap, according to Simpson. “The weld needs to be perfect every time to ensure a high level of quality control,” says Simpson.

Dukane worked with Cap-N-Lock from the concept stage and provided feasibility studies, design assistance, tooling, and on-site support. Dukane ultimately provided a turnkey assembly system which included custom tooling (horn), a custom nesting (holding) fixture, and a press system.

The locking cap is sold as an aftermarket product for $9.99 at Save Mart and Ralph’s supermarkets on the West Coast. It is also available at and will soon be offered at pharmacies.

Wednesday, April 13, 2011

Dukane RFI Filter for Ultrasonic Plastic Welders

Dukane Corporation is a global provider of ultrasonic plastic welders for thermoplastic materials. Our welding equipment is designed with a high quality RFI power line filters to meet FCC and CE requirements for conducted emissions. The RFI (Radio Frequency Interference) is an unwanted noise generated by a wide variety of electronic and electrical devices. Ultrasonic welders which generate unwanted radio frequency energy greater than 10 kHz must comply with the government and safety agency requirements.  The RFI is the radiation or conduction of radio frequency energy (or electronic noise) produced by electrical and electronic devices at levels that interfere with the operation of adjacent equipment. Frequency ranges of most concern are 10 kHz to 30 MHz for conducted emission and 30MHz to 1 GHz for radiated emission.
Most electrical and electronic equipment can produce RFI noise. The most common sources include components such as switching power supplies, relays, motors, triacs and equipment such as personal computers, printers, medical instrumentation, industrial controls and electronic games.  An electrical and electronic device emits RFI in two ways: a) radiated RFI is emitted directly into the environment from the equipment itself;  b) conducted RFI is released from components and equipment through the power line cord into the AC power line network. This conducted RFI can affect the performance of other devices on the same network.

Radiated RFI is usually controlled by providing proper shielding in the enclosure of the equipment.  Conducted RFI can be attenuated to satisfactory levels by including a power line filter in the system. The filter suppresses conducted noise leaving the unit, reducing RFI to acceptable levels. It also helps to lower the susceptibility of the equipment to incoming power line noise that can affect its performance. Since no electronic equipment operates in total isolation, manufacturers must protect their own equipment from RFI noise produced by other devices functioning in close proximity or on the same power line. They are also responsible for making sure that their equipment does not transmit offending RFI noise, resulting in the malfunction of other devices.

RFI power line filter consisting of a multiple-port network of passive components arranged as a dual low-pass filter, the RFI filter attenuates radio frequency energy to acceptable levels, while permitting the power frequency current to pass through with little or no attenuation. Their function, essentially, is to trap noise and to prevent it from entering or leaving equipment. RFI is conducted through a power line in two modes. Asymmetric or common mode noise occurs between the line and ground. Symmetric or differential mode is measured from line to line.  Common Mode: Also known as line-to-ground noise measured between the power line and ground potential. Differential Mode: Also known as line-to-line noise measured between the lines of power. Power line filters are designed to attenuate either one or both modes of noise. The need for one design over another will depend on the magnitude of each noise type  present. The attenuation is measured in dB (decibels) at various frequencies of signal.

Dukane power line RFI filters are designed to meet both FCC and CISPR 11 with 5dB to10dB below the limit. They are generally built with three-pole filter networks to meet greatly varying electromagnetic environments for medical electronic and industrial control equipments.

The governments and safety agencies of major industrial countries, including the United States, Canada, and the European Union have established noise emission regulations that are focused on digital and other electronic equipment. The most important guidelines for Ultrasonic Welder are FCC CFR 47 (Parts 18) in the United States and CISPR 11 in the European Union.

FCC CFR 47 (Part 18) Industrial, Scientific, and Medical equipment (ISM), for Ultrasonic equipment. A category in which the RF energy is used to excite or drive an electromechanical transducer for the production of sonic or ultrasonic mechanical energy for industrial, scientific, medical or other none communication purposes.

The European Union also has harmonized the national regulations and has established the international standard CISPR 11(EN55011) which covers conducted emission for Industrial, Scientific and Medical (ISM) radio frequency equipment.

The following tests were performed to determine that Dukane Ultrasonic products are in compliance with the council of Europe and technical specifications of the EMC Directive 2004/108/EC, Low Voltage Directive 2006/95/EC and Machinery Directive 2006/42/EC.

EN 60204-1    Safety of Machinery - Part 1: Specification for General Requirements.
EN 12100-1 &2    Safety of Machinery – Basic concepts, general principles for design.
ISO 13854    Minimum gaps to avoid crushing of parts of human body.

EN 61000-6-2 and EN 61000-6-4_Generic Emission & Immunity:
EN 55011:          Conducted Emissions – 150 kHz to 30 MHz
                          Radiated Emissions – 30 MHz to 1GHZ
EN61000-4-2:     Electrostatic Discharge (ESD)   4kV (contact), 8kV (air)
EN61000-4-3:     Radiated Radio Frequency Immunity –  80 MHz to 1000 MHz
EN61000-4-4:     Electrical Fast Transient Immunity
EN61000-4-5:     Surge Immunity
EN61000-4-6      Conducted Immunity – 150 kHz to 80 MHz
EN61000-4-8      Magnetic Field Immunity
EN61000-4-11    Voltage Dips, Short Interruptions and Voltage Variation Immunity

Attenuation: The decrease in intensity or absorption of electromagnetic energy. Expressed in dB.
Conducted Interference: Electromagnetic signals entering a device through direct connection.
b: The level of electromagnetic disturbances equipment causes to its environment.
Filter: Remove electrical noise or interference from the power line by cleaning up the sine wave.
Immunity: The level to which equipment is immune to electromagnetic disturbances in its environment
Impedance: Opposition to the flow of electrical current when a given voltage is applied.
Inductor: Passive component that produces a voltage proportional to the change in current.  Measured in Henrys.
Insertion Loss: The electromagnetic signal loss resulting from the insertion of a filter in a transmission line. Expressed in dB.

Wednesday, April 6, 2011

What method would I use for Multiple Slit Applications - Narrow Gauge or Standard Slitting?

This question can be answered different ways but let’s discuss the difference from the two methods of Ultrasonic Narrow Gauge Slitting and Standard Ultrasonic Slitting.

Narrow Gauge Slitting is when a series of Individual Slitting Modules are positioned under a Long Ultrasonic Bar Horn usually about 9” in length. Depending on the Centerlines and number of Slits will determine how Modules will be required and how many 9” horns will be required. The actual Slitting anvils are fixed/locked in the module and do not rotate and are spring loaded. The Modules are designed to allow the Slitting anvil to be repositioned to a new working surface once a wear spot occurs on the anvil and then locked back in place. This will allow you to use the full diameter of the Slitting anvil. Once the entire anvil is worn then it would be replaced with a new one. This method is commonly used when Narrow goods are required. Please see attached picture of a Narrow Gauge system these Slits are done off of one Roll approximately 36” wide approximately 21 Slits.

Standard Slitting is a single station Slitter that Slit’s one section of the Fabric. Normally uses a 1” Diameter Horn and also has a fixed anvil that is mounted on an air cylinder. These anvils also have the ability to be repositioned to maximize the working surface of the Anvil once wear occurs. The air cylinder allows for more precise control of Anvil pressure versus the Narrow Gauge spring loaded design modules. Standard Slitting is used when the Slit requirements of the Fabric are wide widths usually greater than 9” wide. Depending on the width of the Roll being slit will determine how many Slitting stations will be required. Please see picture of a UFF1 Slitter Frame.

The two methods mentioned above are typical ways of Ultrasonic Slitting and are very commonly used in the Fabric & Film market. Depending on the requirements of the application we often replace the fixed Anvil method with Individual Driven Rotating Anvils. The rotating anvils in most applications will perform better and usually increase line speeds. Using the driven anvils will require drive motors or can use one common shaft with individual air cylinders. These situations will require qualified machine Builders. Always use either a fixed anvil or a Driven anvil free spinning anvils are not recommended. Please see picture of Driven anvils on a common shaft with individual air pressure.