Case Overview

Longwang has successfully provided a comprehensive manufacturing and sub-component assembly solution to a number of global heavy machinery customers. By integrating multi-station deep drawing, progressive stamping, precision riveting, and automated surface electroplating (yellow zinc and transparent zinc coatings) processes, Longwang strictly adhered to the TS16949/ISO9001 quality standards.

Case Details

Project Background

Given the critical role of industrial machinery, the complex load-bearing components within them must be manufactured by reliable and stable suppliers. Although these parts may appear to be merely "simple" stamped components, their manufacturing involves significant technical challenges—primarily due to the fact that they operate under conditions of intense vibration and high stress. Consequently, the operating environment demands exceptional structural integrity, strict dimensional tolerances, and superior salt-spray corrosion resistance.

Manufacturing Challenges

Processing Challenges: These components require multiple deep-drawing stages, necessitating high precision and excellent formability to prevent thinning, micro-cracking, or surface wrinkling in high-stress radius areas. Furthermore, the process involves significant and non-uniform material deformation; without process optimization, localized necking, cracking, or thinning can occur, directly compromising the part's structural load-bearing capacity.

Surface Treatment: As this batch consists of components with varying shapes and thicknesses, achieving uniform zinc coating thickness and consistent color—while avoiding bare spots or surface scratches—is difficult; these are common quality issues in the small-batch production of mixed hardware parts. Furthermore, given features such as deep cavities, internal threads, and overlapping riveted seams, meeting the requirement for 96 to 120 hours of neutral salt spray resistance without causing zinc buildup or hydrogen embrittlement poses a significant challenge.

Supply Requirements: The client's monthly demand fluctuates by up to 40% depending on the project cycle. Suppliers require flexible production scheduling to avoid stockouts and overstocking, while maintaining a stable defect rate during periods of significant capacity scaling.

Customer Pain Points

The client’s previous projects utilized a model involving multiple suppliers for segmented processing. Consequently, issues such as axial misalignment and non-compliant geometric tolerances frequently arose. These defects led to problems during subsequent assembly—such as poor interlocking, inadequate coaxiality in riveting, or insufficient pull-out force—thereby increasing costs associated with manual re-assembly and rework. As a result, delivery times significantly exceeded expectations.

Longwang Solution

Process Optimization: The Longwang engineering team optimized the blanking, deep drawing, and embossing processes using advanced CAE stamping simulation, effectively preventing material fatigue and springback.

Automated Riveting: Riveting fixtures are customized to requirements, allowing bushings and locking hooks to be assembled directly into the stamping process while ensuring 100% concentricity and pull-out strength.

Surface Treatment: We have implemented a fully automated electroplating production line to ensure uniform current distribution and consistent zinc coating thickness across all components. A 100% visual and dimensional inspection step is performed after plating to eliminate parts with surface defects.

Quality Inspection: We subject all components to Coordinate Measuring Machine (CMM) inspection, optical image measurement, and 100% torque/push-pull testing. We also utilize a comprehensive MES-based traceability system and maintain safety stock levels for semi-finished stamped parts. This enables us to effectively manage demand fluctuations, shorten lead times for finished products, and maintain consistent quality standards even during peak periods.

Targeted Services

As a one-stop service provider, Longwang integrates the entire process of "pressing - deep stretching - tapping - riveting - surface treatment - assembly" and takes full responsibility for it. This eliminates the ambiguity of responsibilities and unclear rights between multiple factories as well as the time-consuming process of intermediate material circulation. At the same time, Longwan has its own independent inspection process, using a three-coordinate measuring instrument (CMM) and an optical image measuring instrument to conduct comprehensive inspections or frequent spot checks on form and position tolerances as well as GD&T specifications. At the same time, 100% push and pull force/torque tests are introduced to ensure the firmness of the assembly and prevent non-conforming products from flowing to the next process. Therefore, in this cooperation, Longwan has significantly shortened the original 45-day delivery cycle to within 21 days.

Results Achieved

Zero-defect Delivery: Achieved a production yield of 99.4% on the first run, fully meeting all GD&T specifications with zero instances of coaxiality misalignment.

Cost Reduction: By utilizing progressive stamping processes, automated in-line riveting technology, and an integrated one-stop supply solution, Longwang eliminated secondary manual assembly steps. This reduced the customer's total procurement costs by 18% and eliminated additional expenses associated with incoming quality inspections, rework, and assembly mismatches.

Product Quality: All components passed the 120-hour Neutral Salt Spray (NSS) test with no white rust observed.

Rapid Scaling: The average order lead time was reduced from 45 days to 21 days, and the client lodged no formal quality complaints during the first full year of partnership.

Why This Project Matters

This project demonstrates Longwang’s ability to go beyond supplying individual stamped parts; the company can provide industrial equipment manufacturers with perfectly matched, ready-to-assemble component kits, effectively addressing key supply chain pain points. At the same time, the project further expands Longwang’s solution design capabilities within the industrial infrastructure sector. Longwang is now equipped to provide robust, cost-effective metal manufacturing services—fully compliant with global market standards—for applications ranging from automotive powertrains and heavy agricultural machinery to industrial enclosures. For global industrial clients, the project showcases Longwang’s strengths in manufacturing capabilities, procurement process simplification, total cost reduction, and the enhancement of long-term product reliability.