Performance Testing the Pointer Wheel Package to Avoid Damages during Drop in handling and shipping environment

Introduction

In the recent past, packaging has been increasingly recognized as a significant factor in a company’s market share and value. The significance of packaging has come to be increasingly recognized in export as well as in marketing of a wide range of consumer goods and industrial products. Good packaging equals increased sales.
Goods damaged in transit or arriving at the destination in an unacceptable condition become less valuable, also it affects the profit and reputation of the manufacturer and the consumer’s perception of the product. Effort should be taken to understand the importance of packaging, thereby to avoid the loss and damage cost incurred during transport and delivery.

Importance of Packaging:

Some of the major significance of packaging can be detailed as follows:

  • Can make a product more convenient to use or store, easier to identify or promote or to send out a message.
  • Can make the important difference to a marketing strategy by meeting customers’ needs better.
  • Packaging plays a key role in brand promotion and management. Packaging is of great importance in the final choice the consumer will make, because it directly involves convenience, appeal, information and branding.
  • Packaging is especially important in certain industry where future sales may be based largely on the quality, integrity and performance of a company’s previous delivery
  • The paramount concern of packaging is the reachability of the product without any damage. No matter where and how the products are transported or shipped, they arrive at the customer’s door in working condition without need of repair or adjustment.

Possible Causes accounting for the Product Damage

The damage in the product may happen due to any of the following reasons.

  • The shipper had not adequately packaged the item.
  • The carrier had imposed excessive force along the way reaching the destination.

Testing the packaged product for mechanical loads

Packaged goods are frequently transported that are particularly sensitive to mechanical loads. These must be protected against the effects of jolts, shocks, vibrations and pressure.
There are four main hazards incurred during the transport of the products, which are listed below

  • Drops and impacts
  • Compression forces
  • Vibration
  • Climatic variations

Drop impact testing evaluates the ability of a package to protect the product against collisions that occur in the distribution environment. Whether the package is dropped, knocked or simply banged around, the drop impacts can cause product damage. To conduct a drop impact test, the package is allowed to free-fall onto corners, edges, and flat surfaces which are shown below.

A Case Study: Drop testing of pointer wheel package

One of our customers as a global manufacturer, they supply notable volume of automotive parts, auto components and automobile accessories to the leading OEMs. Instrument clusters is one of the major product supplied to various four wheeler and two wheeler manufacturers across the globe. This instrument cluster parts are manufactured at different units and are assembled in the main unit.
So the parts of the instrument cluster need to be shipped from different units to the main unit and assembled here. Various parts of the instrument cluster are arriving at the destination in an unacceptable condition, which becomes unusable. The most frequently damaged part during this process is the pointer wheel.

In this study, the behavior and the damages caused to the pointer wheel, package tray and the corrugate box are analyzed in detail with a finite element model by accomplishing the drop test analyses.
The pointer wheel is of two parts a wheel and a needle, the wheel is made of High impact polystyrene and the needle is made from steel. A set of pointer wheels are packed in a tray. The package tray is made of High impact polystyrene.

Testing the package in LSDyna Environment:

The finite element analysis of this study is conducted using explicit nonlinear finite element code LS-DYNA. Drop test experiments are conducted in order to determine the critical regions in the assembly and the results are compared with the ones obtained from FEA. The FEA model can be used to provide any further improvements on the new structure and the packaging module of the pointer wheel.
In this simulation drop analysis is carried with two methodologies to understand the behavior/ damage caused to the pointer wheel, package tray and the corrugate box.

  • Initially the package tray is dropped to observe the impact on the tray and the pointer wheel
  • The complete package containing ten pointer wheel trays have been dropped to study the behavior of the package, trays and the pointer wheels.

Primary study: Dropping the Package tray along with pointer wheel:

The model consists of the package tray and 84 pointer wheels. The package tray is dropped from the height of 1meter at 45-degree inclination.
The finite element analysis of this study is carried out in LSDyna environment, in the finite element model, the tray is dropped from a predefined height with an initial velocity in order to decrease analysis time. The finite element model is generated using HYPERMESH.

It is observed that packaging tray absorbs most of the impact energy when it impacts rigid ground. Due to the impact the pointer wheels are coming out of the tray hitting the floor.

Secondary study: Dropping complete package which is to be shipped:

The complete package containing ten pointer wheel trays have been dropped to study the behavior of the package, trays and the pointer wheels. The orientation of the package is the most fragile corner, which is the package is inclined at 45 degree in both the vertical and horizontal directions with the rigid floor.

Complete Package with 10 trays of pointer wheel

Drop orientation: Most fragile corner

In order to validate the paper material model, a simple Box compression test (BCT) is conducted on a Box compression tester in the lab. The Box compression test is performed by placing the box on a flat platform and pressing it downwards from the top. The same is correlated in FEA simulation. The finite element model of this test setup can be seen in below figure. FEA simulation of this test is successfully performed in LS-DYNA.

Experimental Box Compression Test

Box Compression Test in LSDyna Environment

The correlation involves a trial and error method of evaluating the material properties, the BCT is performed in the LSDyna environment measuring the deflection of the corrugated panel and the peak force is calculated. The force output is compared with the experimental value.

Mat 2 – orthotropic elastic material model is used for packaging module. Because of the complex and highly varied behavior paper is regarded as a homogenous continuum with liner elastic orthotropic properties.
The flowchart explains the methodology used in validating the material properties of the paper box.

Once the material model is validated, the complete package containing ten trays with 84 wheels packed in a single tray. The package is dropped from the height of 1m at 45-degree inclination, entire package is impacting at 4429mm/sec on rigid floor.

Inclined drop test simulation is performed to determine the critical regions of the mechanical structure and the packaging module. It is seen that the critical regions include especially the components that come to contact with bottom foam. Parts at the inclined side of the package is the most affected parts during impact to the ground.

Summary:

In this paper, drop test is conducted in order to determine the critical regions of the package module. Packaging module is analyzed in detail and verification of the results are done by checking the deformation behavior of packaging module during impact.
We could confirm the flaws in the packaging within a test environment by using a combination of box compression testing, to obtain the material model and a drop analysis, determine the critical regions of the package module. The problem was recorded, feasible suggestions were provided and the customer went back to their supplier to find a solution.

2019-01-14T09:57:50+00:00