Bursting force measures how much force a sheet material can take before breaking, commonly used in packing goods. Foil and paper products are the most commonly tested materials. The Mullen test calculates the pressure on the sheet at the time of rupture, measured in psi. The underlying structure of the sheet influences its burst strength.
Bursting force is a measure that shows how much force an object can take before it breaks. This measurement applies only to sheet materials, such as cloth, paper, or plastic. When discussing non-sheet materials, such as how much force a chain can handle, it is more common to use tensile strength as a measure. Bursting force is commonly indicated when packing goods. Shippers will then know that their packaging is strong enough to support the weight of the materials inside.
The only materials that have a burst strength are foil and paper products are the most commonly tested material. These paper products are typically used to ship heavy materials or goods with irregular shapes that are hard on the packaging, such as sharp edges or sharp corners. Other materials, such as fabrics or plastic sheets, also have burst strength, but these rarely need to be tested.
The bursting strength of a substance is typically found using a Mullen test. The sheet is held between two clamps and tightened. At this point, the clamps create an even horizontal pressure on the material. The sheet is taut, but not pulled. When in this state, the sheet can withstand more pressure than when in any other state.
An inflatable bladder slowly fills with air, creating an even pressure throughout the tarp. As the air pressure inside the bladder increases, so does the pressure exerted on the sheet. Eventually, the pressure on the sheet is too much and the material breaks. The pressure in the bladder is monitored to calculate the pressure on the paper at the time of rupture. The final amount is usually measured in pounds per square inch (psi).
When a Mullen test is used to find the strength of a paper shipping material, the test results are often printed directly on the container. This data, along with a handful of other metrics, make up the building block of information commonly found on commercial packaging. Often, this printed material is part of a proprietary system and is difficult for the average consumer to read.
There are several factors that influence the burst strength of a material. One of the main factors is the underlying structure of the sheet. Sheets with long solid lines or fibers are generally stronger than those made from shorter materials or composites. In packaging, the corrugation improves the overall burst strength of the board, especially when it goes against the grain of the corrugation.
Protect your devices with Threat Protection by NordVPN
