Punch Press Research Articles

Characterization and evaluation of okra gum as a tablet binder

The type and amount of binders decisively influence the characteristics of tablets prepared by wet granulation procedure. Commonly used binders like acacia, gelatin, starch and hydrolyzed starch have natural origin. The aim of this study was to evaluate the effectiveness of a new binder extracted from Hibiscus esculentus (Okra gum) in tableting. Okra gum was extracted from the pods of Okra fruit by maceration in distilled water followed by filtration of viscous solution as well as precipitation of gum extract by using acetone. To evaluate the binder effectiveness, two models, including a placebo formulation (lactose) and a drug formulation (Acetaminophen, Ibuprofen, and/or Calcium acetate) were evaluated. Granules were prepared by different concentrations (0.5-6 %w/w) of Okra gum and tableted using a Kilian single punch press. Cornstarch (12.5 % w/w) and P.V.P (22 %w/w) were employed as the standard binders for comparison. The physical properties of the granulates and those of the tablets including disintegration time and dissolution rate were studied. The properties of granulates (bulk and tapped density, granule strength, flowability) as well as those of tablets (hardness, friability, disintegration time) were generally good. Moreover, the physical properties of Ibuprofen and Calcium acetate tablets containing Okra gum showed sufficient hardness, desirable disintegration time and low friability. The percent of drug released after 45 minutes were 15 %, 44 % and 96 % for Acetaminophen, Ibuprofen and Calcium acetate tablets, respectively. Okra gum produces some tablet formulations with good hardness and friability. However, this binder prolongs the dissolution rate of some slightly soluble drugs and hence may be good candidate for sustained release formulations. (Symecko C., Rhodes C, et.al.,1995)

Investigation of the speckle pattern effect for displacement assessments by DIC

PurposeThis study aims to investigate the effect of speckle pattern on displacement measurements using different speckle diameters and coverage ratios.Design/methodology/approachIn order to compare the coverage ratio and speckle diameter during the evaluation of the correlation of digital images (DIC) study, template speckle plates were produced on a computer numerical control (CNC) punch press with 600 punches per minute. After the speckle plates were manufactured, the speckled pattern was randomly painted on a plain white side through the manufactured template plates, and then tensile tests were performed under the same loading conditions for each sample to observe displacement variation via correlation parameters.FindingsDuring the manufacturing of templates with thin plates, a punch diameter of less than 1.7 mm will cause tool failure; therefore, uniform speckle size can be assessed before operation. A higher coverage ratio resulted in more accurate and reliable results in displacement data. With smaller coverage, the facet size should be increased to achieve favorable results.Research limitations/implicationsIf thick template plates are selected, speckle painting cannot be done properly; therefore, template thickness shall also be assessed before operation.Practical implicationsFor randomly distributed DIC templates, increasing coverage beyond 50% does not make sense due to difficulties in the production process in the punch press.Originality/valueEvaluating DIC results via templates manufactured in a punch press with different speckle diameters and coverage ratios is a new topic in literature.

Preparation of tofacitinib sustained-release tablets using hot melt extrusion technology

This study aimed to develop a tablet that shows a drug release profile similar to the tofacitinib sustained-release tablet (Xeljanz XR®; OROS™) using hot melt extrusion technology. Tofacitinib citrate was selected as the drug. HPMCAS, HPMCP, and Kollidon VA64 were used as thermoplastic polymers to prepare a hot-melt extrudate. The extrudate was obtained from a twin screw extruder and pelletizer. The granules were compressed using a single punch press machine and then coated. TGA, DSC, XRD, FT-IR, and SEM were performed on the hot melt extrudate to understand its physicochemical properties. Dissolution tests were performed using the paddle method (USP Apparatus II). The results showed that the crystallinity state of tofacitinib changed to amorphous after the hot melt extrusion process; however, no chemical change was observed. The drug release profile was similar to that of Xeljanz XR®, which has an initial lag time owing to its OROS™ formulation; a coating process was performed to obtain a similar drug release profile. The lag time was controlled by adjusting the thickness of the coating layer. Moreover, the extrudate size and compression force during tableting did not significantly affect drug release. In conclusion, the new tofacitinib sustained-release tablet prepared using hot melt extrusion showed a drug release behavior similar to that of Xeljanz XR®.

Human-robot collaborative task planning for assembly system productivity enhancement

PurposeIn the current era of Industry 4.0, the manufacturing industries are striving toward mass production with mass customization by considering human–robot collaboration. This study aims to propose the reconfiguration of assembly systems by incorporating multiple humans with robots using a human–robot task allocation (HRTA) to enhance productivity.Design/methodology/approachA human–robot task scheduling approach has been developed by considering task suitability, resource availability and resource selection through multicriteria optimization using the Linear Regression with Optimal Point and Minimum Distance Calculation algorithm. Using line-balancing techniques, the approach estimates the optimum number of resources required for assembly tasks operating by minimum idle time.FindingsThe task allocation schedule for a case study involving a punching press was solved using human–robot collaboration, and the approach incorporated the optimum number of appropriate resources to handle different types of proportion of resources.Originality/valueThis proposed work integrates the task allocation by human–robot collaboration and decrease the idle time of resource by integrating optimum number of resources.

Method for calculating deformations and stresses in the impact press fuse

A solution to the problem of longitudinal impact of a slider with a punch on a forging for an impact press is obtained by the finite difference method. An algorithm for calculating the maximum deformations and stresses of an elastic polyurethane bushing when a self-restoring fuse is triggered by force for a КД2124 crank press with a force of 250 kN is presented. The resulting solution can be used to develop a concept for constructing a means of protecting impact crank presses from technological overloads. Keywords: crank punching press, slider-crank mechanism, dynamic loads, deformations, stresses, force fuse, finite difference method. gord349@mail.ru, erof.vi@yandex.ru, acidwolfvx@rambler.ru, oxulkovs@mail.ru, aplehov@mail.ru

AUTOMATIC OIL SHELL EJECTION

The purpose of this project is to investigate and solve the problem of sticking between die and sheet metal in a punch press. Initially, the problem was thought to be caused by high pressure, but lowering the pressure did not fix the problem. Further investigation revealed that the sticking was due to the magnetic properties of the die. demagnetizing the die with a demagnetizer has been found to be an effective solution. Another proposed solution is to apply a Tin coating to the die surface to prevent sticking. The aim of this project is to provide an effective solution to reduce sticking in punch presses.

Evaluation of Newly Designed and Traditional Punches in Manufacturing of Scored ODTs.

To overcome difficulties in splitting, uneven breaking and inconsistent dosing frequently reported with scored tablets, a novel punch was proposed for the manufacturing of easy breakable tablets (EBTs). In this work, the performance of the EBT punch was investigated vs. a ridged one for traditional breakable tablets (TBTs) using a furosemide powder formulation for orally disintegrating tablets (ODTs). A Face Centered Central Composite Design was applied to investigate the influence of punch type, compaction force, tablet weight and press rotation speed on the mechanical properties of ODTs, their behavior in aqueous fluids and aptitude for splitting. Mass uniformity and adequate crushing strength, friability, water uptake, disintegration and wetting times were obtained from both TBTs and EBTs. Interestingly, more favorable splitting behavior was shown by tablets manufactured by the novel punch, in view of lower mass loss and portion mass variability after breaking. The ease of breaking, accuracy of subdivision and mass loss of ODTs were also evaluated by a volunteer (n = 20) panel test. Less difficulty was found in splitting EBTs than TBTs (p < 0.05), and a larger number of tablets were properly broken into four parts. Thus, this study proved the usefulness of the EBT punch in overcoming drawbacks associated with divisible tablets.

Development of a combined bulging-piercing technique to reduce forming load for a long semihollow stepped part

This paper aims to develop a new forming technique to manufacture a long semihollow stepped part. Traditionally, hot backward extrusion is used, but this technique is not suitable because it requires a very high forming load to act on the die and punch, especially at the contact between the punch and workpiece. As a result, the service life of the punch is very low. Therefore, a new technique to overcome this problem is needed. A combined bulging–piercing technique was proposed and developed in this research. The main concept of this technique is to bulge the part by upsetting the workpiece between the punch and counterpunch to generate high frictional contact pressure, which will help to restrain the material from sliding down into the die cavity during the piercing step. In other words, this technique utilizes frictional force at the die–workpiece interface to reduce the forming load of the punch. Finite element modeling was employed to investigate and determine a suitable level of the bulging which can reduce the forming load without generating any significantly high force to the counterpunch. Only experiments with the minimum forming load were selected and implemented to validate this concept because other conditions with high load will risk damaging the punch and machine press of the product line. The results show that this technique can reduce the forming load by almost 40% and also control a good concentricity of the part and reduce the wall thickness variation.

Punch press noise control through partial acoustic enclosure: A Field Study

Punch press noise control through partial acoustic enclosure: A Field Study

Automation by CAM in Punching Press Machine

Automation by CAM in Punching Press Machine

25 years ago march 1996

Information Society Initiative launched; Centreline Machine Tool Company relocates from Hinckley to Nuneaton; RCS introduces a new punch press module for customised hole punching and notching machine; and benefits of the Internet explained to businesses

Influence of Shape and Size of Foundation on Vibration Reduction of High-Speed Punching Press Based on Multidomain Modeling

With the aid of multidomain modeling method, the vibration of a high-speed punching press was modeled and predicted, and the influence of the installation of foundation, as well as the shape and size parameters of the foundation on the vibration of the punching press, is discussed. The rectangular foundation size with the best effect of vibration reduction under the premise of saving the installation area was obtained. The validity of the multidomain model of the high-speed punching press with the foundation for vibration reduction is verified, by comparing the simulation results with the experimental results.

A blacksmith's tale: use of a rare earth magnet to facilitate safe removal of a metallic fragment from the face.

A 48-year-old blacksmith presented to A&E after sustaining facial injuries while operating a metal punch press. Radiographs revealed the presence of a metallic foreign body within the cheek, but this was clinically impalpable. By using a neodymium rare earth magnet extraorally, it was possible to identify the position of the fragment several centimetres lateral to the entry wound. Triangulation of the fragment's position allowed retrieval under local anaesthetic through the original penetration wound, without need for cross sectional imaging or extensive exploration under general anaesthetic. This case highlights an application for magnets in detection and removal of impalpable metallic foreign bodies embedded in superficial soft tissues.

A General Framework for Sustainability Assessment of Sheet Metalworking Processes

The sheet metalworking industries possess minimal knowledge in the area of sustainability despite having served as sub-contractors to various industrial sectors. This also highlights that suitable indicators for measuring the sustainability performance of sheet metalworking operations are poorly addressed. As sustainability assessment is regarded as a vital part of sustainable development, this paper has been aimed at establishing a general framework for sustainability assessment of sheet metalworking processes. The main attention was paid to two important processes—the cutting operations with a CNC turret punch press machine and sheet metal bending operations with CNC press brake machine. Stepwise guidelines to implement the proposed framework in sheet metalworking industries are consequently presented. Besides, this study contributes to developing an applicable sustainability indicator set for assessing such manufacturing processes. It makes a valuable contribution to advancing the narrow body of knowledge on the under-researched scope.

Energy accumulation in mechanical resonance and its use in drive systems of impact machines

An innovative method utilizing the phenomenon of mechanical resonance in machine drive systems of impact machines has been described. Energy accumulated in mechanical resonance is typically multiple times larger than the continuously supplied excitation energy. The amount of accumulated energy depends on the amplitude of vibration, mass and stiffness of system and present energy dissipation mechanisms. This form of energy can be extracted periodically each time after the amplitude of vibration reaches its maximum value. This effect could be implemented in drive systems of periodically operating machines, such as punching machines and presses. Significant reduction of energy demand in machines that use mechanical resonance in comparison with conventional machines was confirmed by means of simulations and experiments. Accumulation of the energy at mechanical resonance and its sequential extraction were presented together with a new prototype resonance punching press.

25 this Month

Manufacturing misses out; investment support; punch press tooling maker automates; EDM agency news; Hydrafeed bar feeder success; Fastems created; Deckel Maho Gildemeister story continues; Europe’s open CNC project

Elastic recovery in roll compaction simulation.

Roll compaction/dry granulation is a widely used granulation method in the pharmaceutical industry. The simulation of the process is of great interest, especially in the early phase of formulation development of solid dosage forms. The hybrid modeling approach allows to predict the roll compaction process parameters to produce ribbons with a desired solid fraction. Based on the process parameters, compacts (ribblets) of the same solid fraction are produced on a single punch press. So far, the prediction accuracy for the solid fraction of the ribbons was not satisfactory. It was found that the lack in prediction accuracy was due to the elastic recovery, which was not considered in the model. In this study, the fast in-die and the slow out-of-die elastic recovery of different excipients with varying compaction properties were investigated. A method was established to compensate for the elastic recovery of compacts in roll compaction simulation and to improve the prediction accuracy of the solid fraction considerably. The results were successfully implemented into the model through an additional learning step. Moreover, the findings were transferred to the mimicking of an API containing formulation. By modeling, it was possible to accurately predict the process settings to obtain ribbons with the desired solid fraction using only a small amount of material.

Electrode Perforation Induced Performance Increase in Vanadium Redox Flow Batteries

In the pursuit of providing reliable energy to an increasingly energy dependent society, the development of electrochemical devices that can meet various demand output conditions is not only important, but necessary. The Redox Flow Battery (RFB) is one option that can provide for this demand by offering the ability to modularize energy and power at a high standard of safety over a long product lifetime. While the RFB has already been successfully implemented at the commercial scale, there exists a need to research further methods towards cost/kWh reduction and power density increase. A conventional cell stack for a RFB consists of end plates that sandwich a set of current collectors, bipolar plates, electrodes, and an exchange membrane arranged in a symmetrical cell.[1] In this study we explore the potential of electrode perforation towards increases in battery performance using cell reactive resistivity as a performance indicator. The perforation method in this study has been chosen for its commercial feasibility and ease of implementation; it has been achieved through the use of a scalable punch press to bore a matrix of holes with variable diameter dimensions of 1-2 mm and a range of hole densities from ~3 holes/cm2 to ~6 holes/cm2. Three sets of serpentine bipolar plates were also prepared with varying turn densities of 4, 7, and 11. These bipolar plates were created keeping effective channel diameter consistent while varying depth and width. The channel to ridge ratios in all three plates were kept at 1:1 and the effect of electrode perforation was explored. The test cells were assembled with the aforementioned bipolar plates and SGL 39AA carbon paper electrodes activated at 600°C for 30 min. Nafion NR211 was used as the membrane material. The cell was assembled with 0.5 mm silicon spacers and 3 sheets of activated SGL 39AA for both the positive and negative electrodes. The electrolyte for the experiment was a 1.5M Vanadium solution prepared with VOSO4-nH2O, 20%w/w H2SO4, and DI water. An averaged improvement in reactive resistivity of 20.8% from 0.262 Ohms*cm2 to 0.207 Ohms*cm2 was demonstrated for a set of three serpentine flow fields via the mechanical perforation of 1 mm diameter holes at a density of ~3 holes/cm2. It is noted that reactive resistivity was separated out of ASR resistivity using a LCR meter to measure frequency independent bulk effects which is referred to as conductive resistance.[2] Reactive resistivity was further broken down into mass transport, charge transfer, and diffusion resistivities through the analysis of relaxation times during cell charge and discharge. Through this, the effect of perforated electrodes for charge transfer resistivity and mass transfer resistivity are shown. (Figure 1) It is realized that electrode perforation via 1 mm bores improves all subsections of reactive resistivity, and it is hypothesized that electrode perforation allows for increased reactant mass transport to the membrane side electrode partition, which has been shown to exhibit lower electrode volumetric utilization than the bipolar plate side electrode partition.[3] Is it also observed that the difference in performances of the 4, 7, 11 turn bipolar plates, which were significant and proportional to channel depth when evaluated with non-perforated electrodes showed a significant decrease in variance with the introduction of perforated electrodes. It can thus be extrapolated that the electrode modification method yields a higher apparent consequence to cell performance than the variation of channel density for the same active electrode area. In conclusion, it is shown that the introduction of 1 mm diameter perforations at ~3 holes/cm2 in carbon paper electrodes is effective in improving performance in a vanadium redox flow cell with serpentine flow channels. The over perforation of electrodes at ~6 holes/cm2 was noted to have the decreased performance associated with an extreme reduction in useable electrode surface area. Pressure drop analysis also reveals that the introduction of perforated electrodes reduces the pump pressure needed to operate at the same nominal flow rate. It is thus realized that the introduction of perforations in electrode material can improve both system efficiency and cell efficiency in the VRFB. [1] N. Tokuda et al.: “Development of a Redox Flow Battery System”, SEI Technical Review, No. 151 (2000) [2] J. Ross Madonald.: “Simplified impedance/frequency response results for intrinsically conducting solids and liquids”, The Journal of Chemical Physics 61, 3977 (1974); doi: 10.1063/1.1681691 [3] Q. Liu et al.: “In Situ potential disctribution measurement in an all-vanadium flow battery”, Chem. Commun. 49, 6292-6294 (2013); doi: 10.1039/C3CC42092B Figure 1

Spark plasma sintering of quadruplet ZrB2–SiC–ZrC–Cf composites

Spark plasma sintering (SPS) route was employed for preparation of quadruplet ZrB2–SiC–ZrC–Cf ultrahigh temperature ceramic matrix composites (UHTCMC). Zirconium diboride and silicon carbide powders with a constant ZrB2:SiC volume ratio of 4:1 were selected as the baseline. Mixtures of ZrB2–SiC were co-reinforced with zirconium carbide (ZrC: 0–10 vol%) and carbon fiber (Cf: 0–5 vol%), taking into account a constant ratio of 2:1 for ZrC:Cf components. The sintered composite samples, processed at 1800 °C for 5 min and 30 MPa punch press under vacuumed atmosphere, were characterized by densitometry, field emission scanning electron microscopy, energy dispersive spectroscopy, X-ray diffractometry as well as mechanical tests such as hardness and flexural strength measurements. The results verified that the composite co-reinforced with 5 vol% ZrC and 2.5 vol% Cf had the optimal characteristics, i.e., it reached a relative density of 99.6%, a hardness of 18 GPa and a flexural strength of 565 MPa.

Extension of the Lean 5S Methodology to 6S with An Additional Layer to Ensure Occupational Safety and Health Levels

This paper proposes an expansion of the Lean 5S methodology, which includes the concept of Safety–Security as 6S. Implementation was done by a standardized process tested in a pilot area that is part of the Integrated Industrial Manufacturing System Laboratory at the Higher Technical School of Engineering (ICAI). The additional 6S phase (Safety-Security) thoroughly reviews all areas of an industrial plant by analyzing the risks at each workstation, which let employees be fitted out with protection resources depending on each of their personal characteristics and to guarantee the safety of the workstation by strictly complying with occupational safety and health and machinery use standards, which must hold a CE certificate of compliance. The main objective was to increase the scope of 5S methodology to respond to the occupational safety and health needs for machines required in optimizing production processes. It is important to remember that companies must guarantee that their employees use personal protection equipment (PPE) at their work posts or stations that protect them properly from risks to their health and safety and that cannot be prevented or sufficiently limited by using collective means of protection or by adopting work organization measures. The industrial resources employed in the pilot area chosen for 6S implementation were a sheet metal deformation and cutting line comprised of a punch press, feeder, and winder, as well as a conventional machine tool with minimum safety specifications and without CE certification. Until now, there had been no plans to implement a 6S tool in this laboratory. However, given that the existing safety risk to operators is high, the implementation has led to obtaining optimal results, which justify the success of the 6S methodology proposal. In short, it lets us advance towards the zero accident target.