Client Background
MINGHANG, a reliable glass mason jars manufacturer, has recently joined hands with a boutique dried fruit workshop located in the USA. The customer wanted a tailor-made glass mason jar with the body covered in the fruit pattern embossed and an airtight aluminum lid with the natural bamboo feature. Their purpose was to promote their organic, artisanal brand image and, at the same time, provide freshness and attractive shelf appearance. MINGHANG was selected by the brand due to our demonstrable skill in precision glass molding, top-quality airtight sealing technology, and uniform product clarity throughout large production batches.
Challenge
The mason jars had the challenges in two major aspects:
- Thread Precision for Airtight Sealing: Air leaks or lids that have become loose as a result of even the tiniest thread measurements variations are the situations, which, because of product freshness, are most likely to be the cause of failure.
- Embossing Clarity on Curved Surfaces: The company brand embossing clarity on the curved mason jar body to be very crisp and detailed was the reason for exact mold depth and the pressure being evenly distributed during forming.
Cause Analysis
Following the thorough examination, our technical team came to the conclusion that the main source of the problem was the tiny variances of the thread cooling and contraction rates at different places along the threads during production that caused sealing. As for the embossing clarity issue, it was due to the uneven application of the pressure inside the mold cavity, especially the areas where the curvature was more steep. To fix this issue, we performed numerous molding trials, adjusted the temperature for the annealing process, and enhanced the mold polishing in order to get uniform texture and depth. Throughout this time, our engineers cooperated closely with the client’s design team to make sure that each embossed detail was a reflection of their brand identity.
The Mason Jar with Lid – 70-280ml Glass Food Storage
Embossed Glass Mason Jars – Custom120-620ml Containers
Solution
- Facilitated the use of precision CNC-machined molds for achieving the thread tolerance to be within ±0.05mm.
- Started a new multi-stage annealing schedule as a way of glass contraction stabilization and the removal of sealing inconsistencies.
- Used laser-assisted embossing alignment to make sure that the pressure was always evenly distributed on the curved surfaces.
- They carried out sealing pressure tests and vacuum leakage simulations prior to large-scale production.
Result
The sealing of the custom glass mason jars along with the outstanding clarity of the fruit motif being embossed has been successfully achieved in the final batch. The jars not only retained the freshness for long periods but also visually supported the brand’s premium, eco-conscious identity. The US client was very happy with the product both in terms of the functionality and the design which is a reason for the long-term cooperation with MINGHANG as their preferred glass mason jars manufacturer.
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