Posted by AC&M

Tank Trucks move products over our highways and streets that are critical to our lives. They also move sensitive and sometimes dangerous products. The contents of nearly every tanker and storage tank are secured for tamper detection and identification. Most often the seals used for this are Plastic Strap Seals for numerous reasons.


Plastic strap seals come in various styles and sizes and are flexible to fit the wide variety of closures found on tankers. These closures include mostly valves and hatches, but also covers for metering devices and control levers for fill and discharge. Tank trucks and tanks are often custom made so the versatility of fit is important.

American Casting & Mfg. makes a comprehensive line of plastic seals including the types most commonly used on tank trucks, storage tanks, and related operations.

Adjustable pull-up seals come in large and small sizes and offer several choices in pull strength, band thickness and lock types. These options help the user match the strength of the seal to the job while making it possible to pass it through the many different configurations of hatch and valve systems found on tankers.

Both the adjustable pull-up seals and fixed length seals are available with the latest in strong plastic or metal locking mechanisms for greater resistance to opening, or simple single-material lock systems for excellent tamper evidence at a lower cost.


One of the needs in tamper evident sealing is to record and document both the installing and removal of a seal for tracking and other control purposes. The markings should be clear and readable by the person responsible for keeping that information. A plastic strap seal comes in bright colors and can be marked in multiple ways to make the digits, letters or codes highly contrasted and visible to the user. That readability is very important in maintaining accurate records.


Color variation is an important feature for the unique identity of seals. Plastic seals are readily available in a wide range of standard colors, and can even be custom colored in large enough quantities. Color coding might be used to indicate things like the type of contents in the tank, the company who owns it, the driver, a date, batch or other variables that the user needs to quickly see.


Each security seal should have a unique color and marking combination. This helps prevent operating errors or unauthorized use of replacement look-alike seals by bad actors.

Plastic seals can be marked with hot stamp foil, laser, and permanent print. The markings can range from simple lettering and numbering to bar codes and QR codes. The user’s logo or specialized symbols can also be put on the seals.

Options also include the ability to mark a seal with symbols accepted or required by regulatory agencies like FMCSA or various state and national groups, both inside and outside of government. Stamping of symbols for hazmat, flammable materials, various chemicals, plus food, medical or sanitary products are among those. Also plastic seals can be readily marked with the identity or logo of a company’s division or operating station.


Many applications on tankers and in tank wash require a large number of seals that will meet quality and performance standards within a budget. An example would be a milk tanker that may use multiple seals daily, amounting to thousands per year. Extrapolate that to a fleet of milk tankers and seal costs are then a major factor in operating costs. Users need to strike a balance between quality, functionality, and cost.

Another example of high consumption is tank wash operations. They typically must seal each tank after wash to assure that it is empty, cleaned, and cleared for use again. In these circumstances users turn to the most basic plastic strap seals because they will provide good tamper evidence, marking and color options to identify the type of contents and good readable serial numbers for record keeping, all at a cost within their budget.


Because these seals have been on the market for decades, there are many types that are recognized for their consistent quality and reliability. AC&M has been making seals since 1910 and produces seals of all types. We are registered to meet quality standards of ISO-9001:2015 for Manufacture of Military and Commercial Tamper Evident Security Seals.

AC&M is also a founding member of the International Seal Manufacturers Association and is compliant with all relevant quality and operating standards of the Association.

You can purchase seals from AC&M in any quantity directly by phone, or smaller lots for immediate delivery anytime at the online store at

If you have questions regarding your applications for seals, AC&Ms experienced experts are available to help with answers. We are knowledgeable in all industries and all types of uses. This includes tank trucks, tank wash, and tank storage operations.

Contact a seal specialist at: or call 1-800-342-0333 in the US or 516-349-7010 from outside the US.