Using Moldex3D and LS-DYNA to Reduce Warpage in an Injection Molded Scanner Part

 

Customer Profile
liteon
  • Customer: Lite-On Technology
  • Industry: Electronics
  • Solution: Moldex3D Advanced Solution Package / FEA Interface
  • Region: Taiwan
Lite-On Technology is a leading provider of innovative products for both global and domestic markets, including imaging products, enclosures, power supplies and LEDs. Lite-On’s primary objective for all product lines is to be number one in Taiwan and within the top 3 in the global market.(Source: https://www.liteon.com/ ) 

Executive Summary

Contact Image Sensor (CIS) is a key component of scanners. In this case, the holder of the CIS deformed during the shipment due to the relaxation of residual stress. The distortion of the product led to the separation of the assembled parts, and further degraded the image quality. To address this issue, Lite-On Technology used Moldex3D Advanced Solution Package and Moldex3D FEA Interface incorporating LS-DYNA to explore how the process-induced residual stress affects the product deformation. As a result, Lite-On Technology was able to deliver defect free products on time by utilizing Moldex3D to improve the injection molding process.

Challenges

  • Strip products tend to cause flow imbalance
  • The deformation range should be under 0.4mm in the horizontal and 0.8mm in the vertical
  • The deformation would lead to the separation of the assembled parts

Solutions

With the assistance of Moldex3D and LS-DYNA, the warpage of the product can be reduced by changing different gate locations and process conditions without increasing any cost.

 

Benefits

  • Resolved mold flow-imbalance issues
  • Reduced X-axis deformation by 50% (from 0.34 mm to 0.17 mm)
  • Solved the separation problem of the assembled parts
  • Ensure a high level of product precision

Case Study

The Contact Image Sensor (CIS) holder usually requires high precision. Lite-On Technology combined Moldex3D simulation capabilities and LS-DYNA structural analysis to improve the dimensional stability of the CIS holder of a scanner and ensure it to be within tolerance after molding.

using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-1Fig. 1  A CIS holder part (in red circled)

With Moldex3D Advanced Solution Package, Lite-On Technology simulated the molding conditions of the original design based on the traditional injection molding method. The results showed that unbalanced flow and high volumetric shrinkage occurred in the main region of the part and might cause potential deformation risks. At 99.9% of the filling stage, the filling time of the unfilled areas is 0.7 sec slower than the filled area (Fig. 2). The inadequate gate number resulted in concentrated pressure near the melt inlet. It is observed from Fig. 3 that high volumetric shrinkage occurred in the red area near the gates. The local high shrinkage areas can cause internal voids or sink marks when the part cools. In this case, high precision and the external appearance quality are very important, so warpage has become more critical than ever before.

using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-2Fig. 2  The flow front of original design at 99.9% of the filling stage 
using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-3Fig. 3  The volumetric shrinkage for the cross section of this original design

In order to minimize flow imbalances and improve warpage, Lite-On Technology changed the gate locations and removed the center gates as shown in Fig. 4. The outer gates were moved 40 mm outward from the original locations. According to Moldex3D simulation results in Fig. 5, the revised design was able to effectively diminish the warpage displacement significantly.

using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-4Fig. 4  The model of the revised design
using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-5Fig. 5  The X-axis deformation of the revised design

Lite-On Technology conducted experiments to validate the simulation results. In Fig. 6, the analysis results of the original design show prominent deformation. On the contrary, in the revised design shown in Fig. 7, there is no obvious high shrinkage area; the warpage can be lessened greatly. Based on the above verification, Moldex3D simulation results are in a good agreement with the results from the actual mold trial.

using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-6Fig. 6  The actual deformation measured and the simulation result of Moldex3D for the original design
using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-7Fig. 7  The actual deformation measured and the simulation result of Moldex3D for the revised design

Moldex3D allows users to map the simulation data onto structural analysis models to simulate the effects of mounting a part during an assembly operation. Lite-On Technology carried out the structural analysis through LS-DYNA. Thus, the assembly-induced deformation and stress can be considered in the linear elastic analysis in LS-DYNA as shown in Fig. 8. The deformation of CIS Holder can lead to compression forces on the glass part, so the large deformation can make the glass part separate from the CIS Holder. In addition, the glass part of the revised design requires approximately 75% less stress than that of the original design.

using-moldex3d-and-ls-dyna-to-reduce-warpage-in-an-injection-molded-scanner-part-8Fig. 8  Stress variation in assembly position after the glass part is mounted on the CIS holder

Results

With the integration of Moldex3D and LS-DYNA, the warpage of the part alone or the warpage of the assembly can be predicted. With Moldex3D FEA Interface, the users can export the process-induced fiber orientation, thermo-mechanical properties and residual stress data from Moldex3D to LS-DYNA for more realistic structural analysis. Moldex3D helps ensure that structural analysis can fully consider process-induced material properties. As a result, the integration of Moldex3D injection molding simulation and LS-DYNA structural analysis helps Lite-On produce quality parts in a cost-effective manner. This also gives Lite-On Technology greater confidence in plastic part design and manufacturing.


Excavator Travel Reducer

Excavator travel reducer are used in construction machinery such as wheel excavators, crawler excavators, and skid steer loaders, as well as in the fields of mining machinery and port machinery.

I. Product Advantages

1. Complete production line

ZHTE HYDRAULIC has a complete set of production and processing equipment from raw material processing to manufacturing.

2. Complete models

ZHTE HYDRAULIC excavator travel reducer have a wide range of models, which are widely applicable to different brands and models of wheel excavators, crawler excavators, skid steer loaders and other equipment on the market, meeting diverse market demands and providing users with great convenience and flexibility in choice.

3. Product quality assurance

ZHTE HYDRAULIC excavator travel reducer have obtained EU CE certification. From the purchase of steel to production and processing, each process has been strictly inspected by professionals to ensure the high quality and reliability of the products.

4. Production process

1) Forging blank (inspection)
2) Rough turning (inspection)
3) Normalizing (inspection)
4) Finish turning (inspection)
5) Gear shaping (inspection)
6) Drilling (inspection)
7) Chamfering (inspection)
8) Carburizing treatment (inspection)
9) Gear chamfering and deburring (inspection)
10) Shot blasting treatment (inspection)
11) Inspection according to drawings, warehousing, and rust prevention (inspection)
12) Pre-assembly inspection
13) Pre-assembly cleaning
14) Assembly and installation
15) Product form and product performance test, pre-delivery test
16) Adding lubricating grease
17) Painting treatment (inspection)
18) Packaging and boxing (inspection)
19) Finished product warehousing after packaging
ZHTE HYDRAULIC excavator travel reducer conducts full-process inspection with strict quality control and guaranteed quality.

II. Structural Composition:

1. Gear:

The gear is the core component of the excavator travel reducer and is responsible for transmitting power and realizing the deceleration function. Different types of excavator travel reducer may use different gear types, such as planetary gears. The hardened gear can withstand a large load and ensure the service life of the reducer.

2. Housing:

The housing plays a role in protecting the internal structure and also provides installation and support for gears and other components. The material and manufacturing process of the housing have an important impact on the strength and sealing performance of the reducer. ZHTE HYDRAULIC has a professional casting line, and each process is inspected by professionals to ensure quality.

3. Shaft:

It is used to connect gears and other components and transmit power. The material and processing accuracy requirements of the shaft are relatively high to ensure stability and reliability under high-speed rotation and high load.

4. Bearing:

It supports the rotation of the shaft and reduces friction and wear. High-quality bearings can improve the operating efficiency and service life of the reducer.

III. Working Principle:

Excavator travel reducer usually use the meshing of gears to achieve the function of deceleration and torque increase. When the high-speed rotating power provided by power sources such as motors or engines is input into the reducer, through the gear transmission system inside the reducer, the speed is reduced and the torque is increased at the same time to meet the power requirements of walking equipment under different working conditions. For example, planetary gear reducers achieve efficient deceleration transmission through the cooperation of the sun gear, planetary gears, and ring gear.

IV. Performance Characteristics:

1. Large reduction ratio:

It can reduce the input high-speed rotation to a low speed suitable for walking equipment and provide sufficient torque for the equipment to overcome various resistances.

2. Strong load-carrying capacity:

Since walking equipment usually needs to carry a large weight and load, excavator travel reducer need to have a high load-carrying capacity. By using high-quality materials and advanced manufacturing processes, excavator travel reducer can operate stably for a long time in harsh working environments.

3. Reliable operation:

After strict design and testing, excavator travel reducer have good reliability and stability and can ensure the normal operation of walking equipment.

V. Maintenance:

1. Regularly change lubricating oil:

Lubricating oil can reduce friction and wear between gears and extend the service life of the reducer. Lubricating oil needs to be changed regularly according to the usage of the reducer and the manufacturer's recommendations.

2. Check the wear condition of parts:

Regularly check the wear condition of parts such as gears, shafts, and bearings, and replace severely worn parts in time.

3. Keep clean:

Keep the reducer clean and avoid dust, debris, etc. from entering the reducer and affecting its normal operation.

Our products

include: Excavator Hydraulic Pump, Excavator Final Drive ,Excavator Swing Motor, Excavator Travel Reducer, Excavator Swing Reducer, Swing Bearing ,Hydraulic Breaker

Excavator Travel Reducer,Original Excavator Travel Reducer,Travel Reducer For Excavator,Excavator Travel Reducer Assembly

XINGTAI ZHONGWEI ZHUOTE HYDRAULIC TECHNOLOGY CO.,LTD , https://www.zwzhtehydraulic.com

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