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ASTM D5331 Mechanical Handling of Unitized Loads

ASTM D5331 testing covers the ability of unitized films to survive mechanical handling. As an ISTA and ISO 17025 certified lab, we realize the importance of ASTM D5331 testing. Meeting the ASTM D5331 unitized load requirements can be difficult. We understand the challenges and guide companies through the process.

When packages do not meet the requirements, we assist with finding solutions. Keystone creates an accurate test plan to eliminate expensive over-testing. We have a reputation of helping customers achieve their package certifications. Lastly, we take pride in providing comprehensive reports shortly after completion of the testing.

Request a quote and find out first hand about our competitive pricing, timely process, and outstanding reputation. Contact us to receive more information on ASTM D5331 stretch wrap testing.

Summary of ASTM D5331 Mechanical Handling of Loads Secured with Stretch Wrap Information

This ASTM sustainability and mechanical handling test method applies to common means of handling, including: forklift, push/pull, clamp truck, crane, and spade lift-type handling systems. ASTM package test levels can change to better reflect known levels of intensity in the field.

ASTM D5331 package testing focuses on the sample preparation and evaluation when assessing the performance of stretch film for load unitizing.

For the purposes of this standard the following terms are defined:

          Large shipping case or create- a shipping container (any material) of size and weight that requires mechanical handling. This unit can weigh from 100lbs to many tons. It can be secured or carried by a base or pallet. A frame may be provided to stabilize rigidity throughout the container.

          Spade lift attachment- a lift truck attachment that is used for top handling products. The products can include interlocking flange cartons (IFC), folded cap, or folded flap style cartons.

          Unitized load– two or more packages that are wrapped or banded together as one shipping unit. 

Scope of ASTM D5331 Mechanical Handling Testing 

When unitized, packages generally weigh more than 100 lbs. The packages can be unitized using shrink wrap, banding, strapping, taping, or gluing. The unitized load can but does not necessarily have to include a pallet or slip sheet.

ASTM D5331 is often used to compare the performance of unitizing films. However, it can also be used to compare one kind of wrapping material used in different wrap cycles.

It is important to note that there is not a direct correlation established between test result and field performance. Rather, the test simulates mechanical handling during all distribution phases.

Significance of ASTM D5331 Unitized Loads Package Testing

There are two apparatuses used in this test. First the load wrapping apparatus and second, the mechanical handling apparatus. The load wrapping apparatus is a machine that wraps the test load. This method should be as close as possible to the actual method of wrapping that is used in production prior to shipping. The mechanical handling will be determined by the test method. 

To prepare the test loads, begin by arranging the packages in a manner that is similar to actual production. They may be loaded in layers or stacked on a pallet or slip sheet. The load should then be wrapped with the unitizing film using a predetermined percent stretch and wrap cycle.  This is predetermined by the user using their discretion.

The unitized load is recommended to be left untouched for a minimum of 16 hours before conducting the test. This time allows the stretched wrapping material to reach equilibrium of its stress retention forces. The test will then be conducted according to the test procedure chosen.

ASTM sustainability and transit test procedures include palletized load, spade lift, clamp handling, and push/pull handling. At the conclusion of the test, the laboratory will record data and compile a test report that includes all the information outlined in the ASTM D5331 standard.

Expert Unitized Loads Secured with Stretch Wrap Films Package Testing

Our team strives to give our customers more time and energy on product development instead of testing. In addition to ASTM D5311 testing, Keystone has a full scope of expertise including vibration, high impact shock, and sterile barrier. We can accommodate flexible and rigid packages of all sizes, including large pallets.

Contact us to learn first hand why so many companies partner with Keystone to achieve their ASTM D5331 methods of mechanical handling certification needs.