​Redundant Sealing to Protect Bulk Products with Liners

​Redundant Sealing to Protect Bulk Products with Liners

Posted by Steve Diebold

Redundant Sealing to Protect Bulk Products with Liners

Chemicals, pharmaceuticals, food products, minerals and more are often bulk shipped in drums and totes with removeable liners of plastic or rubber. These typically contain products of very high value or vulnerability, that need seals to provide evidence of opening or tampering. Anything that might lead to pilferage, theft or outside contamination is in need of security sealing. This is especially true of food products and additives supplied for human consumption where purity is a critical factor for safety and quality control.

The outer container, usually a drum or tote, has allowance for applying a tamper evident seal. A seal on the locking ring of a drum or the sides of covers helps verify that the container has not been opened. This assurance of the integrity of the contents is critical.


When drums or other heavy containers are handled by machines, transported in trucks or rail cars, stacked and moved in warehouse etc, there is always a risk that the seal or the locking part of the drum or tote could be broken or damaged enough for the seal to be rendered useless --or even completely missing. Then the product inside cannot be verified for purity. It probably has no value and must be discarded or sent back for reprocessing and/or testing.

Typically, the seal on this type of container is a padlock type seal or a plastic pull up seal. Shippers could use stronger seals of steel or cable but if the drum’s locking ring or tabs on totes are broken the strength of the seal is irrelevant. The proof that it was not opened is gone if the seal or lock system is destroyed or missing. This type of damage is not uncommon and can cost hundreds or thousands of dollars in losses for a single drum or tote.

To reduce the chances of such losses most liner systems are made with extra material at the top so that it functions like a bag. The liner can be twisted closed and cinched with a tight tamper evident seal. This gives a second layer of protection. If the outer seal is damaged the inner bag seal provides clear evidence that the contents were not exposed or accessed. The product can still be used.


AC&M manufacturers some of the most effective pull-up seals for bag closure available. Our PS360 and DTZIP seals have optional gripping teeth for stronger hold and prevention of slipping or twisting after installing. These are great seals for most bag type liner applications.

ACM also offers a unique printed Nylon Tie with a stainless steel lock tab. Nylon is favored where a cleaner, stronger and more durable plastic is important. It is often preferred for sensitive products, or those in long term storage. It has more resistance to breaking, cracking, or crazing or temperature extremes vs other plastics. It does not dry, deteriorate or shed microscopic particles over time, which adds assurance of the contents’ purity, plus nylon has a long shelf life.


As a leading manufacturer of seals since 1910 American Casting & Mfg. Corporation has the experience and resources to help with any application for seals including liners for drums and totes and countless others. Our web site contains detailed information on all of our latest products for this and any needs.

We invite you to ask any questions or request advice, product information, samples or other information on seals and their use. Call or chat online during EDT business hours or contact us anytime through the web site.