Adhesives, dispensing systems

Table 4.22 Commercially available adhesive dispensing systems... 

Table 4.22. Commercially Available Adhesive Dispensing Systems... 

The company will operate as part of Nordson s Adhesive Dispensing Systems segment. 

At the close of the deal, Verbruggen had current fiscal year estimated sales of 8 million ( 11 million) and employed approximately 40 people. The company will operate as part of Nordson s Adhesive Dispensing Systems segment. Nordson reportedly expects the acquisition to be neutral to the company s earnings in the first full year of operation. 

The cycle time has an important bearing on the investment required to automate the system and the number of operators or workstations that may be necessary. Whether manual, semi-automatic or automatic, the dispensing equipment system specified will depend on the type of application and workplace conditions, such as dispense rate, parts per hour, operator availability and materials handling. Adhesive dispense systems are available for most production lines varying from bench-top applicators to fully automated robotic units with dispense times of <50 ms. 

In some automated adhesive dispense systems for two-part adhesives (e.g., epoxies and acrylics) a spit cycle is incorporated into the machine such that if the mixer nozzle is left idle for a pre-determined time, a small quantity of adhesive is dispensed into a container to prevent the adhesive curing in the mixer nozzle. 

Adhesive dispensing systems are used for delivering either single or multiple-component adhesives from their original containers to an application point where the adhesive can be applied to the workpiece in either metered shots or continuous beads. Adhesives with a wide range of viscosities can be processed in this way by advanced adhesive dispensing systems, from low to high level. 

Adhesive dispensing systems for applying single-component adhesives can be fed by either a pressure-feed container for light viscosity adhesives or ram-mounted dmm pumps for medium to heavy viscosity adhesives. Application can be manual or automatic. 

Multiple-component adhesives, such as epoxy resins, polyurethanes, and silicones, can be processed by piston or gear-type metering and mixing adhesive dispensing systems [6]. 

Two-part adhesives are generally dispensed by volumetric pumps for semiautomated and automated medium- to high-volume assemblies. Metered dispensing systems are easily capable of processing adhesives with mix ratios of 1 1 up to 15 1. 

Interaction between closure and pack (e.g. the black slurry which may occur with aluminium collapsible tubes), and possible adhesion between closure and pack (e.g. as may occur with sugar- or syrup-based products), are typical of what could occur if usage tests were omitted. Simulated use tests are particularly important with aerosols, pump systems, etc., which combine the closure with a dispensing system. 

Chipbonder 3616/ Loctite High speed stencil printing adhesive compatible with DEK Proflow dispense system 32,000/NA 300-550 Rounded High-speed stencil printing up to 152.4 mm/sec (6 in/sec) squeegee pressure (4-6 N/cm)... 

Dispensing System/ Manufacturer Work Area Dimensions (X,Y, in) Z-Axis Travel (in) Dispensing Method/Speed (dph) Applications Examples of Compatible Adhesives... 

Each of these can be complex. Adhesive placement may be as complicated as an independently monitored automated metering, mixing and dispensing system fitted with a pot-life guard - but it could be as simple as manual dispensing from a purpose-made bottle. 

For medium to large adhesive applications, metering and mixing dispense systems are used for applying adhesives like epoxy, polyurethane, polyester, or silicone formulations. Such systems... 

The viscosity of the adhesive is one of the most important factors in deciding the choice of dispense system. Adhesives of a viscosity lower than about 30,000 mPa-s (also known as centipoise) are usually packaged in bottles and above 30,000 mPa-s they... 

One of the most commonly used semi-automatic dispense systems is the pressuretime method and this is extensively used for a wide range of production engineering applications. The adhesive is stored in a pressurised vessel and pressure is applied to force the adhesive to the dispensing tip. There are two distinct variations of the pressure-time method ... 

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