Delta - PE, PP, PVC - Dörken GmbH & Co. KG

Kunststoffe international, 2005-11-21, Barrier Screws for a Broad Material Palette
...ts different throughputs were obtained with the same number of revolutions. Therefore for the analysis the following formulas were used to calculate the dimensionless screw characteristic (Fig. 5): ((Formula_1)) ((Formula_2)) with m : Troughput Δp: Back-pressure, n0: Revolution rate p: Density at the melt temperature n: Potential law exponent D L: Screw diameter and length b, h, φ, i: Channel width, height, pitch angle and number of the metering zone η: Viscosity at the melt tem...

Kunststoffe international, 2005-11-21, Central Vacuum Unit for Blown Film Extrusion
... stations. Modular Structure Particularly Important One particularly important aspect during the planning of the facility was its modular structure so as to make the scheduled extensions as simple as possible. For the entire material supply line, Delta-p GmbH, Waldburg/Germany, drew up the concept in cooperation with the planning people at B+K, supplied all the components, including the entire vacuum and conveying lines, and did the on-site installation. Start-up of the first construction stag...

Kunststoffe international, 2005-11-21, Consumer Protection: Migration Models for the Assessment of Plastic Products
...l and thus produce maximum values by comparison with foods. This distribution gives a mean value of AP70 = 7.7 and a standard deviation of s = 0.76. With a statistic certainty of 95%, this produces a variability in the values for ΔAP70 = 3 of between 6.2 and 9.2. In addition to the molecular mass, the chemical nature and structure of the diffusing substances also has an influence on the diffusion rate. This influence is relatively low, however. If a comparison is drawn, for example, betwee...

Kunststoffe international, 2005-11-21, Cooling in Miniature
...oporous steel through which expanding liquid carbon dioxide flows. Through the use of porous steel inserts, the heat exchange area is enlarged. As a result, the dissipated heat flow improves in line with the following equation: Q = α x A x Δϑ α = heat transfer coefficient A = heat-exchange area Δϑ = temperature difference between mould and medium The principle is shown in Fig. 7 for a test core. For application of this technology, AGA or its present...

Kunststoffe international, 2005-11-21, Cooling Time Reduction by Foam Injection Moulding: It Can Be Done Faster
...cle around the gate region. Consequently, in this wall-thickness range, with sprue design adapted to foam injection moulding, a much greater reduction can be achieved than the decrease from 28 to 22s that is measured (cooling time reduction Δtc = 21,4%). There is an apparent trend for the potential cooling time reduction to decrease as the wall thickness increases. While foamed circular disks with 4mm wall thickness can be demoulded 6s earlier on average (Δtc = 18,5%) than the non-fo...

Kunststoffe international, 2005-11-21, Dashboards Meet Highest Requirements
...ffusion. The surface of a dashboard must withstand intensive UV exposure without any change in properties. Aliphatic TPU is characterised by high UV stability and light fastness so that both the Yellowness Index (Y. I.) and the colour change value delta E remain within very close tolerances (Fig. 3). The high ageing resistance of aliphatic TPU when subjected to UV exposure also has an effect on tensile strength. In a specified test series (Xenon ageing test), this value remained constant (Fig. 4...

Kunststoffe international, 2005-11-21, Design of Radial Spiral Dies
...ig [3]. Rheological Computation Using Network Theory Network theory [2] is based on an analogy between melt stream and electric current. Flow in a melt channel may be described by Ohm's law if voltage U is replaced by the pressure difference Δp. Electric current I and Ohmic resistance R are then replaced by the volumetric flow V and the resistance to flow K. For the computation, the die is broken down into spiral and land segments that are connected up to form a network, as shown in ...

Kunststoffe international, 2005-11-21, For the Car of Tomorrow
... Abrasion Resistant The internationally established Taber abrasion test has shown that ExatecPlus has abrasion resistance close to that of glass and that it thus satisfies the requirements of ECE regulation 43 for windows in front of the B column (Δ haze ≤ 2 %) (Fig. 2). Samples of ExatecPlus are currently undergoing SAE open-air testing in Florida and Arizona and have yet to fail after more than two years. Injection Moulding of Automotive Windows Injection moulding is the only way t...

Kunststoffe international, 2005-11-21, Friction Behaviour of Thermoplastics
...he metal surface at a constant speed (vtest) by the tensile testing arm. The force required for this (F) is determined and recorded by the tensile testing machine. The friction test ends when the tensile testing arm has travelled a preset distance (Δs). The effects of the following parameters on friction were examined: - metal surface, - test temperature and - adhesion (as a consequence of surface reproduction). Table 2 gives a survey of the test series carried out with the two plastics fo...

Kunststoffe international, 2005-11-21, High-performance Plastics: The Right Material for Future Markets
... mind that 60% of the world's population lives in this region. An article in the journal 'Wirtschaftswoche' recently expressed this in a succinct way: half of the world's population can be reached from the Pearl River delta, i.e. from Hong Kong, in five hours' flying time. The rapid industrial and commercial development in China is driving the whole region at the present time. The result is that US, European and Japanese companies are investing preferentially in China and in...

Kunststoffe international, 2005-11-21, Impact Modification Of Thermosets
...mprovement of up to 1000 %. Apart from this, it also becomes clear that the values for the CTBN-modified resin (also shown in Fig. 1) are below those of the polyurethane-modified material. The complex modulus (E*) and the loss factor (damping; tan δ) were determined in a temperature range from 0 to approx. 300°C by means of dynamic-mechanical thermoanalysis (DMTA). Fig. 2A shows the complex modulus as a function of temperature. Through the impact modification, the modulus is lowered, w...

Kunststoffe international, 2005-11-21, Inflow Behaviour in Single-screw Extruders
...arge screws [2, 3]. In high-speed extrusion, a closer look needs to be taken of the feed section. The feed section may be divided into three zones (Fig. 1): - Hopper and feed throat, - Inflow zone, with no pressure build-up along the screw channel (Δp = 0), and - Conveying zone with pressure build-up (Δp > 0). Intensive studies of solids conveying and the design of single-screw machines date back as far as the 1970s [4, 5]. However, the flow of material between the feed hopper and th...

Kunststoffe international, 2005-11-21, Infrared Thermography: Recognising the Optimisation Potential in Injection Moulding
...hing and trimming. Preliminary studies soon revealed thermal problems. Subsequent IR thermography of the moulded parts, performed directly after removal on the gripper hand, revealed temperature differences on the moulded-part surface of up to Δν=64.6°C (Fig.10). These were the reason for poorer quality and cooling times. Analysis of the heat-exchange layout revealed a symmetrical arrangement of the channels, but nothing that could create such high temperature differences. The hot s...

Kunststoffe international, 2005-11-21, Market and Concept: Self-colouring of ABS
...lity, gloss and the mechanical tolerances are concerned, the same quality standards apply as with standard ABS product. With the colour tolerance, the cooperation partners also guarantee a maximum deviation of less than 0.5 Delta E for all colours. Equally high standards when it comes to the logistics: The five partners have undertaken to supply the complete system – consisting of the ABS natural product and the masterbatch – within just 10 working days and to provide expert help within 24 hour...

Kunststoffe international, 2005-11-21, Market Growth Worldwide: Polymethyl Methacrylate (PMMA)
...ecially in the aeronautics and aerospace sectors. This foam, produced exclusively by Degussa, is used as a core material in high-performance composites, such as in the new Airbus A 380, as well as in a range of other Airbus models and Boeing's delta satellite transport rockets. Rohacell makes a key contribution towards more lightweight construction methods and hence permits weight and fuel savings. PMMA films are also increasingly being used to refine other, less resistant substrates. Films...

Kunststoffe international, 2005-11-21, Measurement by Ultrasound: Temperature Fluctuations in the Processing Unit
...ximately 15 minutes can be assigned to a reduction in the melt temperature on account of the negative velocity/temperature coefficient. In order to calculate the spatially-averaged temperature deviation of the melt from the wall temperature ΔT=Tmelt–Twall, the difference Δc(t) between the corrected ultrasonic velocity of the melt and the corrected ultrasonic velocity of the melt in thermal equilibrium (Tmelt=Twall) is multiplied by the reciprocal of the velocity/temperature coefficie...

Kunststoffe international, 2005-11-21, Measuring the Optical Quality of Films
...coordinates a colour location in a three-dimension standard colour system. There are a large number of standard colour systems. The CIELab system has gained great importance in practice and defines such a colour location depending on the brightness ΔL and chroma components a in the red-green range and Δb in the yellow-blue range (Fig. 6). With these values, which are simply computed from the measured data, it is possible to specify an absolute colour value precisely. The change in br...

Kunststoffe international, 2005-11-21, Parts Testing: Long-term Performance of IMD Parts
...ed overall and also occurs at a more uniform rate over the maximum weathering duration of 4000 hours. Here, too, the colour change increases with the degree of stretching. The change in yellow index follows the trend for the colour difference value delta E*. Film A loses a certain amount of its yellowness within the first 1000 hours whereas composite film B yellows more and more with increase in weathering duration and degree of stretching. Comparison with the colour of those areas of the test p...

Kunststoffe international, 2005-11-21, Permanent Antistatic Behaviour
...etermined by means of the measurement electrodes. Structured, conductive zones with diameters of about 10mm and resistivities of 9 ± 2MΩ can be seen at the agglomeration electrodes. There is a strong resistance gradient (Rmax - Rmin)/(Rmin ΔL) of more than 2000mm-1 in this area. The length ΔL of the transition region is estimated at 5mm (see Fig.2(a)). It should be emphasised that the magnitude of the resistance inhomogeneity depends on the electrode configuration used and fall...

Kunststoffe international, 2005-11-21, Plastic Extrusion Dies
...omparison of extrusion pressures at D = 115 s-1, it can be seen that polymer dies have much lower pressure levels than metal dies. The comparison in Fig.2 shows the wall-shear stresses τw. τw is computed from the pressure difference Δp = p3–p4 (cf. Fig.1). This result gives a hint to the possible occurrence of wall slip effects when polymer extrusion dies are used. By direct optical measurement of flow rates, the wall slip effects can be quantified. This was done using Laser-Dopple...

Kunststoffe international, 2005-11-21, Polystyrene Foam: Well Packaged
... and give it its silver-grey colour. Thanks to its superior thermal insulation properties, it is used wherever possible and whenever the customer so wishes. One example is the x°-Control MonoTripleBox, which BASF has developed in conjunction with delta T GmbH of Gießen/Germany. Heat-insulating Dispatch Box The x°-Control MonoTripleBox is a highly insulating Neopor box designed for shipping blood products by post or courier. The box consists of two parts with walls 65 to 80mm thick that can be c...

Kunststoffe international, 2005-11-21, Polyurethane Elastomers in Practice
...tinues to oscillate, the lower the damping will be, the less energy of motion the clamped material will absorb and the less heat will develop inside it. The data that can be established from the torsion pendulum test includes the loss factor (tan δ), a measure of the damping, and also the storage modulus G' of the materials. The latter is a quantitative measure of the stiffness of the material. Figure 3 shows the characteristic curves acquired from a torsion pendulum test of this type....

Kunststoffe international, 2005-11-21, Quality Assurance: Residence-time Measurements and Detection of Melt Heterogeneities
...d/or process parameters through the extruder can be distinguished by calculating correlation functions from the readings of the different channels. The correlation functions were calculated with the aid of the deviation in sound velocity Δc0,i(t)=c0,i(t)-· from its mean value in each channel (i=1, 2, 3, 4). The resultant auto-correlation and cross-correlation functions ((Formula_2)) for channels i=1 to 4 are shown in Fig. 8. Although only small fluctuations in sound velocity are recognis...

Kunststoffe international, 2005-11-21, Runner Design for High-Quality Surfaces
...he case of the film gate, the melt being fed centrally is spread to the width of the film gate by means of a pre-manifold. The pre-manifold should be designed so that the melt requires constant pressure along the channel. For example, the so-called delta manifold is carefully balanced so that the pressure requirement is constant along the length of the flow paths. Surface-sensitive and stress-sensitive parts, such as a polycarbonate cover, are always injected with a film gate to reduce shearing....

Kunststoffe international, 2005-11-21, Simulation Model Confirmed
...e die area and the pressure loss in the channel. Because of the requirement that the flow resistance must have the same value at all flow paths across the die width, the value determined can be set equal to the pressure loss across the island field ΔpI1 and the downstream zones. The two pressure losses DpI1and ΔpD2 are coupled together via the volume flow rate. This volume flow rate can now be computed. Depending on which flow law is chosen, this may have to be done iteratively, sinc...

Kunststoffe international, 2005-11-21, The Economic Alternative: Self Tapping Connections in the Engine Compartment
... fatigue cycles without damage, while insert connections (in this case M4) showed cracking at the lower end (brass-insert/plastic tube interface) [3]. Optimised for Engineering Polymers A current development of the thread-forming screw (type: Delta PT, manufacturer: Ejot) now provides greater reliability. By optimisation of the geometries of the thread and core, especially for connections between and to advanced engineering polymers, it was possible to achieve a significant increase in the pe...

Kunststoffe international, 2005-11-21, The Impulse to Save Energy
...t the fixed mould half by the mould opening and at the movable mould half after ejection of the moulding, and that the heat transition in the mould persists until the end of the cycle. Fig. 5 makes clear that the variation in temperature difference ΔT1 between the melt and mould wall determines the heat transition at the cavity, and the temperature difference ΔT2 between the mould wall and the cooling medium, in conjunction with the prevailing heat-transmission coefficient, determine...

Kunststoffe international, 2005-11-21, Weather-resistant TPE
.... 1 - and subjected to the weathering conditions specified above. After every 1000 h exposure, the change in the surface was checked in colourimetric terms using a colourimeter (grade: Macbeth CE 7000). The overall change is then expressed over the ΔE value, i. e. the higher the measured value, the greater the discolouration of the specimen. Tests were conducted on two TPE types that are currently used in outdoor applications on vehicles. One of these compounds is based on SEBS and one TPE...

Kunststoffe international, 2006-01-31, Implants: Plastics with Programmed Memory
Special Plastics with Programmed Memory Implants. Plastics with shape-memory can "remember" their original shape and resume it again on exposure to heat or UV radiation. Multifunctional materials with an unexpected combination of functionalities, such as biofunctionality, controlled active ingredient release, degradability and shape-memory have a special importance for medical technology, e.g. in minimally invasive surgery. Andreas Lendlein Steffen Kelch Karl Kratz Shape-memory means t...

Kunststoffe international, 2006-05-23, Trends and Products: Masterbatch Manufacturers in Germany
... Schweinfurt/Germany, uses universal carriers in addition to plastic-specific substrates. Apart from colour matching for a multiplicity of applications and markets there are niche products such as odour masterbatches and colourants for rotomoulding. Delta Kunststoffe GmbH, Weeze/Germany, is exclusively specialised in customised development. Special attention is paid to combibatches for demanding and long-lived products in outdoor applications, e.g. artificial turf. A set of additive batches with...

Kunststoffe international, 2006-08-06, Conformal Cooling Channels: Cooling Complex Parts
...rmocouples is indicated in Fig.3. The thermographic images (Fig.5, bottom) essentially make clear the relationships identified in the simulation. The deviations between the simulation and thermographic images can be seen to be quite small (&Delta; θ < 3°C). For circular mould inserts, a cooling system manufactured by a generative method only has slight advantages over a conventional mould insert cooled with a standard as regards the distribution and level of the surface temperature. Analy...

Kunststoffe international, 2006-10-30, Laser Sintering: Functional Prototypes Produced from PEEK
...ures of the plastic, for which energy is required, is shown as an increase in the heat flow supplied and exothermic melt crystallisation as a reduction in energy input, see Fig.4. For polyamide, the width of the melting range (&Delta;Tm = Tm,2 – Tm,1) was determined by DSC measurement as being about 17°C. The temperature difference between the melting and crystallisation temperatures (&Delta;Tw = Tm,1 – Tc,2) was about 32°C. The temperature interval between melting of the material and the start...

Kunststoffe international, 2007-03-15, Industrial Production of Optical Parts
...ness ratio, too, the maxim applies that the greater wall thickness during filling results in a much lower filling pressure. In fact, the wall thickness (h) has a quadratic effect on the filling pressure according to the Hagen-Poiseuille law &Delta;P=(v x 12 x η)/h2. That means, conversely, that the less the wall thickness of a part, the greater its filling pressure must be to achieve the optimum results in production. This is not easy to achieve with conventional injection moulding processes...

Kunststoffe international, 2007-03-15, Use of Primary Energy Increases Energy Efficiency
... was provided with a temperature sensor which served to control the desired temperature of the temperature-control device. By means of this direct regulation system the mould temperature could be reached and maintained with a deviation of &Delta;T = 1°C. This first field test provided early confirmation that natural gas heating in comparison with electric heating reaches the desired temperature distinctly faster while consuming less energy and maintains the product-related mould temperature sub...

Kunststoffe international, 2007-09-19, Cost Effectiveness as Incentive
...or plastic film, is presenting, among other products, its "MSH 110" series for the production of bags with flexible handles, which permit manufacturer in two rows. Like this series, the "V.110 Delta 8" and "Nastrosac 130" machines exhibited permit biodegradable materials to be processed (Fig.25). bfm S.r.l., Solbiate Olona, Italy, is a manufacturer of bag-making and flexographic printing machines. bfm will show its visitors a "BM 180/T/EL" bag-making machine of th...

Kunststoffe international, 2007-09-19, Prior to Film Extrusion
...ng the metering flow, the application must also specify at what intervals the samples are to be drawn. This procedure is standardized, and documented in Namur 40 [3]. The values recommended in Namur 40 are: - Sample measuring time &Delta;t = 1 minute - Number of samples n = 30 - Total measuring time &Delta;ttotal = 30 minutes If a comparison is to be made between continuous metering devices and batch feeders, or between batch feeders, it is necessary to decide on which accuracy specifications ar...

Kunststoffe international, 2007-09-19, Therefore Test, Who Wants to Bind Himself Forever
...dard parameters for 13 different materials. The melt and air temperatures can be regulated separately and the rotary drive is equipped with a speed control (Fig. 10). Quality in the Bag Mobert S.r.l., Castellanza, Italy, is exhibiting its V. 110 Delta 8 film welding machine, a production line for plastic shopping bags. In addition to an automatic packaging unit this includes an image processing system which checks the product before packing and in this way guarantees high quality (Fig. 11). B...

Kunststoffe international, 2007-11-21, Highlights: Lightweight Construction and Bio
...l thermal expansion coefficient. In addition an additive in the material reduces the rate of moisture absorption. Nevertheless the scale change between the different machining and lacquer finish steps is the big challenge. In the case described a delta of 9 mm (Fig.2) must be handled. Also for Noble Bodies Not All is High-grade Steel The noble bodies gladly make use of the weight savings of plastics. The Lamborghini Gallardo Spyder became 5kg lighter using a tailgate made of CFK painted in the...

Kunststoffe international, 2008-02-17, Efficient Design of Pneumatic Conveying Systems
...a result the pressure effectively available from a roots blower for conveying purposes is reduced considerably. Figure 2 shows schematically how the solids-to-air ratio μ decreases with the conveying distance at a predetermined total pressure of &Delta;p. If the overall available pressure &Delta;p is increased the solids-to-air ratio can also be correspondingly increased. To operate an dilute-phase conveying system at higher pressure all sources of compressed air (Fig. 3) other than a blower ...

Kunststoffe international, 2008-05-10, Targeted Assessment of Polypropylene Properties
...ndispensable. For example, as shown in Figure 10, the influencing factors exposure time and adhesive agent content lead to conflicting tendencies between tensile strain at break εB and crack opening displacement &delta;Id as a measure for deformation-determined toughness. Whilst the exposure of two PP/GF materials (PP/GF 1 and PP/GF 2) in water leads to a proportional increase of tensile strain at break εB and crack opening displacement &delta;Id, the use of different adhesive ag...

Kunststoffe international, 2008-09-23, Bonding with Sensitivity
...ents, the range and variety of different requirements is matched only by the range and variety of fasteners. The specialist for self-tapping fasteners, Ejot GmbH & Co. KG, Bad Lasphe, Germany, presented three surprises at the same time. The Ejot Delta PT PS is a new type of fastener with a special thread shape (Fig. 4) for assemblies based on thermosets, which because of their hardness and brittleness pose especially challenging requirements. The threads incorporate special grooves, ...

Kunststoffe international, 2010-04-20, Hot and Cold Molds
..., the required geometry will not be flat, and heating cartridges have the clear advantage in this case due to their malleability. Fig. 1. In contrast to high-performance heating cartridges, ceramic heaters (left) are not malleable (photo: Delta-t; other figures: FH Bielefeld) Fig. 2. The ready-toinstall heating-cooling circuit takes into account the fact that the installation space for heating and cooling is often a bottleneck in the design of injection molds Fig. 3. The temperature of the cavit...

Kunststoffe international, 2010-09-24, Raising the Standards
...me and an also approx. 15 % reduced melt pressure, improved quality and lower production costs. In the automotive sector, high demands are made on the materials in America, Asia and Europe. The properties in the case of the bumpers for the delta platform in the GM Group include toughness and rigidity, high surface quality and paintability, as well as shrink properties. With Daplen EF209AE, Borealis has developed a material meeting these demands in close cooperation with the GM tier 1 supplier, P...

Kunststoffe international, 2011-09-23, Making Connections
...also be displayed graphically to allow a better assessment of difficult welding operations. Hall A4, booth 4108 Ejot Screwed Lightweight Construction At Fakuma, Ejot GmbH & Co. KG, Bad Berleburg, Germany will demonstrate, in particular, the Ejot Delta PT screw’s suitability for lightweight construction with the aid of exhibits. These connecting elements for the direct screwing of plastics are claimed to assist in lightweight construction in various ways. The effectiveness of the screw often ...

Kunststoffe international, 2012-09-17, Faster and Lighter
...s application engineers, who are active around the world and can provide guidance until a product is ready to be launched (Fig. 3). Lightweight design is considered an important trend that is being pursued in an increasing number of areas. The Delta PT steel screw for direct attachment to plastic is a case in point. This screw is intended to contribute to weight savings on the basis of this capability, because the dimensions of the screws can be decreased or the number of attachment points can b...

Kunststoffe international, 2014-03-21, Quality Assurance: Scratch-Resistant
...s in the specification sheet for a new development. The plastic material is then produced with special additives to suit the required purpose. The automakers’ specifications are based on a technically measurable standard deviation of less than Delta E 1,5. In spite of the plastic being modified with corresponding additives, the automotive component’s scratch resistance cannot always be ensured. Important hereby is to find an alternative as quickly as possible and without additional costs. In thi...

Kunststoffe international, 2015-11-23, Early Predictions of Service Life
...nsight into the oxidation stability of a product. IDParametersLower setting limitUpper setting limitAOxygen flow rate [ml/min]3070BSample dimension (excl. height) [mm] 14CSample weight [mg] 5.516.5DIsothermal temperature [°C] 190200EPre-heat temp. Delta [°C]020Determination of the oxidative induction time is growing increasingly important in the field of quality assurance of industrially manufactured products. It is an important indicator of the (oxidation) stability of a sample, allowing early...