Unveiling the Tests Conducted on Vacuum Flasks Before Leaving the Factory: Part One

There are stories in every cup, and warmth in every life. Hello everyone, "Dong Dong's Cup Talk" is here! Today, we've invited Minister Li Hang from our factory's Quality Inspection Department to specifically discuss the tests that stainless steel vacuum flasks undergo before leaving the factory. https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlThe following content is based on Minister Li's narration and has been compiled by me. Due to the extensive content, I will share it in multiple parts.

Hello everyone, I'm Li Hang. I've been working in quality inspection at this factory for fifteen years. Over these years, I've led my team in testing millions of cups, from orders for major domestic supermarkets to stringent projects exported to Europe, America, Japan, and South Korea. https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlAlmost every day, I deal with data related to salt spray, drop tests, and thermal insulation performance. At the same time, I'm also a mother of a six-year-old boy. Every day, when I prepare warm water for my child to take to kindergarten, what concerns me most, just like you, is whether the cup is truly safe, durable, and healthy.

Today, I want to take you behind the scenes of the "graduation ceremony" that every vacuum flask must undergo before leaving the factory, https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlsharing my insights both as a professional and as a mom.

Part One: The "Baptism of Fire" Journey of a Qualified Vacuum Flask

In our factory, every vacuum flask that is about to leave the factory must pass a series of tests comparable to a "baptism of fire." https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlThis is not just a standard requirement but also our commitment to consumers.

1. Salt Spray Test – The Cup's "Corrosion Resistance" Endurance Race

This test simulates extreme environments with high humidity and salt content (such as coastal areas or kitchens), https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlexamining the corrosion resistance of the stainless steel body and paint finish of the cup.

Data Requirements:

We place the cup in a salt spray test chamber and spray it with a 5% sodium chloride solution continuously for 24 to 72 hours. https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlAfter the test, the cup body must not show corrosion points larger than Φ0.5mm, and the paint finish must not blister or peel.

Practical Case:

- Domestic Orders: Typically require a 24-hour test.

- Export Orders to Japan: Japanese clients are extremely meticulous about details. They often require 48-hour or even 72-hour "neutral salt spray tests," with stricter judgment criteria for subtle areas like the cup rim and welding seams. https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlWe once had an order rejected by a Japanese client due to an almost invisible minor discoloration on the inner wall of the cup rim. Since then, we've become even more stringent in our attention to detail.

Mom's Advice:

When choosing a vacuum flask, pay special attention to the cup rim and the welding seams on the cup body (you can focus on the internal welding seam at the bottom of the cup). https://www.zhanyict.com/en/ProductsDetail-VB-10529.htmlIf these areas appear rough or have uneven coloring, it’s likely that the anti-rust工艺 is subpar, making them prone to harboring dirt and rust over long-term use.