Shock and vibration testing are designed to test the wide range of impacts goods may experience during the distribution cycle. These two tests have very specific characteristics, and can be performed independently or jointly within a protocol. In the following article we analyze what these types of tests involve and their main differences.
Shock test vs. vibration test
Shock tests reproduce the different types of impacts goods may receive, thereby helping predict the risks that the load may be subjected to during transportation. These tests arise from the need to reproduce and quantify impacts, shocks and accelerations that the load experiences during handling and distribution, in order to prevent shrinkage and reduce costs.
Shock tests may be divided into two subcategories: drop impact tests and impact tests. The former consist of dropping the goods from a certain height to see how they resist the shock due to gravity itself; while impact tests require goods to be crashed at a certain speed against a surface. Different shock tests may be performed as part of this type, such as crashing the goods against the cart they are travelling on or fastening the load and bumping it with a mobile object.
“These tests arose from the need to reproduce and quantify impacts, shocks and accelerations that the load experiences during handling and distribution”
On the other hand, vibration tests reproduce the vibrations undergone by goods during transport. In order to perform these tests, there are different types of machines, such as the vertical vibration testing systems that only have one degree of freedom, or vertical + pitch & roll systems which have three degrees of freedom and very accurately reproduce the vibrations suffered during the transportation of goods.
Some vibration testing machines allow transportation vibrations to be exactly reproduced during the test as long as a real record of the vibrations experienced during transport is available.
When reproducing shock and vibration testst, it is recommended to perform the vibration test first, and then the impact test. This sequence is so because impact tests tend to significantly damage the packaging, which makes performing a vibration test afterward pointless.
Standards and machinery from performing shock and vibration testing
Both impact and vibration tests are outlined in various standards, which we summarize below:
- Impact test
- ASTM D880
- ASTM D4004
- ISO 2244
- ASTM D5277
- Vibration test
- ASTM D999
- ISO 13355
- ISO 2247
- ASTM D4728
These tests may be applied to any type of good, but they are particularly important when it comes to fragile materials, such as in bottle transportation.
In order to perform these tests, there are different machines that generally use electric or hydraulic actuators to generate the motions. At Safe Load we have both a vertical vibration machine and a vertical + pitch & roll vibration system:
- Vertical vibration machine: it is the most inexpensive way to perform a goods vibration test that, while not completely faithful to what happens in reality, it is useful to make comparative analyses. For example, if a machine performs better than another in a vertical vibration test, it will do so as well in a real situation.
It is also useful to perform current standard tests (ISTA, ASTM,…).
- Vertical + pitch & roll vibration system: enables both the vertical vibrations and the pitch & roll movements that take place during the transportation cycle to be simulated. These machines can reproduce a real transportation record, simulating the power spectrum density (PSD) processed from the vibration records obtained during a specific trip.
Safe Load’s pitch & roll system was patented in the year 2012, while our competition developed theirs last year. Furthermore, we have another great advantage, which is that this pitch & roll module can be mounted on an existing vertical vibration machine. This means that the customer does not need to invest on a new machine.
You might be interested in: Transform your Vertical vibration test system into a multi-axis vibration test system with vertical + pitch & roll
Having this type of machinery available implies not having to depend on third parties to improve the design of your product and packaging. It is also useful for saving costs arising from goods shrinkage, since through these tests, you will be able to optimize the packaging as much as possible. Additionally, testing services may be offered to other companies, which means that you will be able to profit from your investment in the long run.
In summary, having a vertical vibration machine with a pitch & roll system is an excellent option for any company that is concerned over improving its distribution cycle and offering a good service to its customers. If you want more information about these types of machines, get in touch with us and we will be happy to offer you advice.
You can also download for free our ebook Calculate the ROI of investing in packaging testing machines and learn how much you can save with your own transport simulation equipment.