DAREX® Cover, Drum and Pail Compounds
Metallic drums and pails are often used as packaging for transporting industrial goods and food products. DAREX® drum and pail compounds are used to seal the seam channels of double- or triple-seam steel drums and pails. Many drums and pails are also made with an open-top or lid, not seamed, but crimped onto the package. DAREX® Cover Compounds are used to form a seal with the crimped open-top or closing-ring of metal, plastic drum and pail packages.
The Importance of the Sealing Compounds
The hermetic seal performs the following functions:
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Keeps micro-organisms out of the package, probably its most important function;
- Prevents seepage of the pack from the drum or pail;
- Prevents leakage of liquids or vapours into or out of the drums or pails;
- Maintains the desired vacuum or pressure inside
DAREX® sealing compounds meet the needs of the pack
Sealing compounds of high quality must be used after consideration of the requirements of the pack. The proper type, amount and placement of the compounds are required to obtain maximum sealing efficiency, and resistance to leakage caused by abuse of the body and the end in the double or triple seam area.
Optimal Sealants for Different Sealing Technologies
Double or triple seam applications
DAREX® Drum and Pail Compounds are latex dispersions delivered in a liquid form for application. They are typically dried or cured prior to seaming. In some cases, the product may also be applied wet during the seaming operation. The gasket must be properly compressed during the seaming operation. The compressive force results in controlled movement of the gasket, filling the voids resulting from double or triple seam construction. Compound placement in the seam provides robustness and abuse resistance during container transportation.
Cover applications
DAREX® Cover Compounds utilise two different technologies: Latex dispersion for water-based compounds or PVC dispersions for plastisol compounds; both of them are used for open-top metal covers. DAREX® water-based cover compounds utilise a two component system to create a "puffed" gasket with cell structure to fill large channels in some covers and lids. DAREX® Plastisol Cover Compounds utilise a single component, PVC-resin-based technology. Both water-based and PVC cover compound technologies rely upon proper compression of the gasket during the crimping operation to fill the voids in the cover assembly. DAREX® Cover Compounds are delivered in a liquid form for application and in most segments are cured prior to crimping.
Compound Characteristics
DAREX® products are specially formulated to have good chemical resistance to a wide variety of aggressive packs. The excellent performance of DAREX® compounds in contact with different oils or solvents is largely due to the tendency of the compounds to swell slightly in the presence of these packs, providing additional assurance that any leakage path is filled. DAREX® products do not become brittle when dried. They retain their rubbery, elastic characteristic providing abuse resistance and sealing integrity to the package during handling and transportation of the drum or pail.
In order to get the optimum sealing properties, several considerations have to be taken. The first criteria is to match the selection of the compound with the product that is being packed. Then proper storage and compound conditioning prior to application are important. Compound application (placement, volume, film weight and appearance) and correct drying and curing with the right compression of the gasket will provide the best hermetic seal.
Tags
- DAREX®