When investing in line performance, a critical component for success is the Internal Bubble Cooling (IBC) system. Less comprehensive systems of lower quality do not deliver on improved production rates, width tolerance, bubble stability or ease of use. To solve this, D.R. Joseph provides the highest quality system on the market. It is equally important on a mono layer line as it is on an 11-layer line.
The solution from D.R. Joseph is the Geo/Ag IBC Control System, a system designed to collect data and control the bubble differently than any IBC solution on the market. Key features are a special control algorithm designed around the specific process dynamics of large bubbles, special sensor placement around the bubble, oversized flow control equipment and on the fly tuning of a second, final measurement point.
This highly visible xenon lamp flashes based on a configurable set of parameters. The parameters allow management to be alerted whenever the operator uses the system in a manner outside standard operating procedures (for instance, running the system in manual layflat control when the SOP requires running in automatic layflat control) or when there is an internal or external fault. This is particularly useful in the case of a bubble break. The beacon relay can also be wired to trigger an audible alarm.
Air flow related issues make up more than half of the service calls that DRJ takes. Restrictions in airflow can be related to a clog, a collapsed hose, dirty air filter or a leak in the ducting. These sort of issues cause bubble instability, and are often overlooked by maintenance personnel. The 3G IBC system will now detect and point users to the specific airflow path that is blocked.
Layflat control is carried out by ultrasonic sensors as shown on point (A), (shown above). They are strategically placed to make timely adjustments to layflat variances, thereby avoiding control lag. Here, the system adjusts for air loss in nip leaks and pin holes, or layflat gain due to internal thermal expansion or ambient temperature changes.
How it worksThe control feature uses an ultrasonic sensor facing the bottom of the bubble flare to measure neck height, then maintains the set point to within +/- 0.25 inches (6mm) via regulating the air ring blower speed. Neck Height Control is also dependent on feedback provided from the IBC layflat sensors for complete bubble control.
Together with the Internal Bubble Cooling System, it manages both layflat and neck height during startup, hole recovery and normal production. This coordination reduces time to production and improves production rate. When both width control and neck height are easily and automatically controlled, operators gain the confidence to increase extrusion speed without fear of losing bubble control or producing out of spec film.
Benefits to ImplementationControlling and maintaining neck height on high or medium stalk bubbles directly correlates to improved consistency in HDPE / MDPE film dart impact and other film properties related to neck height. Beyond consistent film properties and elimination of dart impact failures, benefits that customers can expect include increased production rate due to improved bubble control and tighter layflat control due to the IBC systems automated width control.
The particular design of fine tuning gap of die head enables manual fine adjustment of gap size; therefore, the molten flow can be of 6 7 % gauge variation. The accessory of IBC enables bubble cooling to be fast and stable cooling from internal side.The die head body is made by S45C or SCM440 (JIS and international standard) steel; its surface treatment is by hard chrome plating or Electrodeless Nickel Alloy plating with same effect of mirror surface. The roundness of die lip make uniformly flow distribution of molten extruded; therefore, excellent thickness control is obtainable. C.Y. is a high-quality Film Thickness Fine Tuning Die Head with IBC Tubing, Fine Tuning Die Head with Internal Bubble Cooling Set. manufacturer from Taiwan since 2009.
The particular design of fine tuning gap of die head enables manual fine adjustment of gap size; therefore, the molten flow can be of 6 7 % gauge variation. The accessory of IBC enables bubble cooling to be fast and stable cooling from internal side.
Based in Taiwan since 2009, Chuo Yii Enterprise Co. has been an air ring and die head manufacturer. Their main products, including Film Thickness Fine Tuning Die Head with IBC Tubing, Packaging Film Dual-Lip Air Ring, Exits Adjustable Type, General Dual-Lip Air Ring and Die Head, etc. C.Y.'s Air Rings are designed for up to 7-layer blown film extrusion line. Air ring for thickness and output control film, low gauge variation, fast cooling and bubble stability, as well as adjustable for dual lip exits, adjusted handles or 360 degree circle nut turning.
Intensive Cooling This air-ring system from Addex directs high-velocity streams of air to create Bernoulli suction forces that pull an extrusion film bubble outward and hold it firmly in place while providing fast cooling. The technology improves the stability of the bubble and allows manufacturers to work with difficult-to-process films more quickly.
What's new A so-called Short Stack configuration, incorporating two more strong streams of air. The system pulls the film bubble through a circular enclosure located between the die and air ring that naturally pulls it into an oversized air ring.
Air always blows on the outside of the bubble to cool the film. To increase production rate, internal bubble cooling can also uses. The film stretches in the longitudinal and circumferential directions during production, resulting in biaxial orientation of the film.
The blowing film of HDPE has resulted in the development of new specialized cooling technology. Because of the linearity of the polymer, it has a pronounced tendency to relax and destroy orientation if temperatures are too high. Meanwhile, processing temperature of HDPE is normally 20 -30 degree higher than temperature of LDPE/LLDPE. Therefore the HDPE bubbles are run with a long stalk (neck) before the bubble force to stretch in the circumferential direction. This allows the melt temperature to drop sufficiently to maintain the cross-direction orientation. Which introduces just before the frost line.
The air ring design had modified to allow this type of processing, and an additional bubble stabilizing iris uses just above the frost line. An internal bubble stabilizer often includes. Newer developments include special air flow guides to produce a more stable bubble and minimize the effect of drafts on the neck region.
Grooved-barrel extruders are an important special case, often used for high-density (HD) PE. If you have one, learn more about how it works. The first zone is water-cooled to prevent sticking and melting there. With plain barrels, too, there may be cooling to avoid sticking in the feed entry passages, but unless there are grooves, this is seldom closely controlled.
Sizing devices may have separate cooling, even those that can vary product dimensions on the fly. A ring of water can be applied to the product as it enters the sizer to cause a little shrinkage and lubricate its entry.
The biggest use of air as coolant is in blown (tubular) thin film, where a hot tube comes out of the die upward (a few go downward or sideways) and an air ring blows air on the emerging surface, which is also expanding and thinning from internal air pressure. The outside air may be cooled to get faster production. As this is a big market, there are many variations on this principle, notably internal bubble cooling and downward extrusion with water plus air as coolants. Irises strip the hot air from the surface so cooler air can come in to gain speed.
Metal roll surfaces are common for cooling most flat sheet, extrusion coating, and some film. Most common for sheet are multi-roll stacks; most are set vertically, and a few are at an angle, even horizontal, and may allow the melt to fall into a nip. Thin films and coatings may have only one big cooling roll which the plastic contacts as it leaves the die (distance adjustable).
In roll cooling, water temperatures are closely controlled with heat exchangers, if needed. Pay attention to center-end differences in die temperatures, which in flat dies may be easier to handle in/on the die (gap, spot insulation and heating, and settings) than in the cooling. Such die changes may be useful for other dies, too, not only flat ones, and all may need a narrow-angle infrared thermometer.
Edges of flat products that are to be trimmed may be enclosed and air-cooled or run thinner to avoid slower cooling and send less trim to regrind. Also, air fans over exposed surfaces (including undersides) can augment cooling.
Cooling fluids may be refrigerated for better cooling, but if too cold, their conveying passages may condense water from the atmosphere and get warmer, so insulation may well pay for itself. Chilled air for blown film is a significant operating cost unless well-managed (with temperature measurements and known desired values).
Reuse of heat from product cooling is not common but possible, and worth attention if it can raise production speed and you can profitably sell the increase. Efficiency of water-cooled lines can often be optimized by passing the product through cut-outs that remove the layer of hot water around the product and, thus, encourage flow of cooler water up close to the product surfaces.
Subcooled flow boiling is becoming an efficient and widely used heat transfer approach in internal combustion engine cooling systems. Bubble evolution behaviors are crucial for understanding the mechanism of subcooled flow boiling. In this study, a diesel engine test platform equipped with endoscopic high-speed photography system was built to investigate the characteristics of boiling bubble. Under various inlet liquid subcoolings and flow rates, the mean bubble diameters and bubble size distributions were measured and analyzed based on the image processing techniques. Most of the bubbles approximated the spherical and ellipsoidal shapes. The bubble size was distributed between 1 and 2.5 mm, and the bubble diameters increased with the decrease of the inlet subcooling and flow rate. The flow rate had a more significant effect on the formation of large boiling bubbles. 59ce067264