In the manufacturing industry of metallic bellows, accurate cost estimation and quotation generation are crucial because the design dimensions and material specifications vary with each OEM order. This study aims to develop a Microsoft Excel-based software that automatically calculates production costs and generates quotations for single-type and double-type circular bellows based on the EJMA (Expansion Joint Manufacturers Association) 10th Edition design standards. The proposed program integrates the essential cost components — raw materials, forming processes, welding, assembly, inspection, and overhead — into a modular calculation system. Using VBA (Visual Basic for Applications), the system allows users to input design parameters (such as pitch, convolution height, mean diameter, and thickness), after which it automatically computes material consumption, manufacturing time, and total cost, providing an itemized quotation sheet. This automation not only reduces manual calculation errors but also significantly shortens the lead time for quotation preparation. The research demonstrates that the developed system achieves cost estimation accuracy within ±3% of actual production costs and can be easily adapted to different bellows configurations, thereby enhancing productivity and competitiveness in OEM manufacturing environments.

The most basic control algorithm of the electric power steering system in the Korean refrigerating cart CoCo was first commercialized as a prototype in 2022 after the Motor Driven Power Steering (Electric Power Steering) was verified and applied to automobiles. In order to overcome the heavy load of small machines such as refrigerating carts weighing 750Kgf, the driver's great power is required, which can cause muscle skeletal disorders, causing many female drivers to complain of pain, and recently applied electric steering technology because it was urgent. In this study, we study a control algorithm that complements the stability of the existing control algorithm applied to the electric power steering device for electric carts and analyze and verify the steering performance of refrigerated carts through analysis using MATLAB/SIMULINK.

EPS(Electric Power Steeing) has been a popular system in the automotive industry since 2000 after the technology and safety was validated. The Korean Refrigerated Carts like Hankook Yogurt Coco was developed for the first time in the world. However this carts system and other small tranporting carts has no EPS. Thus the drivers of carts needed a EPS to avoid the burden when steeing a big weighted cart with 750Kgf as many women drivers complain the pain on their shoulders. This paper describes the application of EPS on Korean refrigerated carts with simulation results and experimental data shows the improvement of steering efforts.

Bellows product is an important part in the area of plant engineering, shipbuilding and petrochemistry. For safety and durability it is necessary to consider lots of factors when designing it. This research developed a metal bellows design software based on EJMA 10th Edition manual. This Bellows software was developed by using Excel software and can be able to design U type of bellows which are Unreinforced Single Bellows, Unreinforced Double Bellows, Reinforced Single Bellows and Reinforced Double Bellows. The already proven bellows model were designed to verify this software. This software would predict the life cycle of a product and produce a company report to be provided to the demanding company. This suggested updated software will be helpful for design engineers to save time and effort.

MDPS control has been a difficult problem for the past two decades. Though there are many ways to control steering feeling, the MDPS control logic is still being upgraded or developed for steering feel improvement. A new point of view in MDPS is proposed by evolution logic, which is a new driver friendly improvement based on the analysis of driver’s driving pattern. As a result of the application of evolution logic, this paper shows that drivers behaviour effecting factors among MDPS parameters will efficiently lead to customers’ satisfaction.

This study performed a finite element stress analysis of pipe system connected by bellows based on APDL(ANSYS Parametric Design Language) customizing. The effects of different shapes of developed pipes for various parameters are studied using the finite element commercial package for this study. The structural behavior of complex pipe structures with bellows was also investigated to study the interactions between bellows and other parts. Based on the ANSYS APDL, the effect of initial axial and lateral displacements, and internal temperature and pressure on the Von Mises stress distribution is also analyzed.