How to choose a reliable vacuum flask?

1. After adding water to the cup, tighten the bottle cap and cup lid in a clockwise direction, placing the cup flat on the table; there should be no water leakage. The connection between the cup lid and the cup mouth should be flexible, with no gaps. Check if the sealing is good.
2. Check if the vacuum insulation of the cup is good. After pouring hot water into the thermos and tightening the bottle cap or cup lid clockwise for 2-3 minutes, touch the outer surface of the cup with your hand. If the cup body shows obvious warmth, it indicates that the product has lost its vacuum and cannot achieve good insulation.
3. Identify the quality of plastic parts: the characteristics of food-grade new plastic are low odor, shiny surface, no burrs, long service life, and not easy to age. The characteristics of ordinary plastic or recycled plastic are strong odor, dull color, many burrs, and plastic that is prone to aging and breaking.
4. A heavier cup is not necessarily better. The depth of the thermos liner is basically consistent with the height of the outer shell (differing by 16-18MM), and the capacity should match the nominal value. Some lower-quality thermoses add sand or cement blocks to the cup to compensate for the missing weight.

How are stainless steel thermos cups produced?

1. Shell processing process
Picking the outer tube – cutting the tube – bulging – segmentation – bulging – rolling the center angle – shrinking the bottom – cutting the bottom – punching the ribs – flat top – bottom punching – flat bottom – cleaning and drying – inspection and knocking – qualified shell
2. Inner shell processing process
Inner pipe picking – pipe cutting – flat pipe – bulging – upper corner rolling – flat top opening – flat bottom opening – thread rolling – cleaning and drying – inspection and knocking – butt welding – water test and leak detection – drying – qualified inner tank
3. Assembly process of outer shell and inner shell
With cup mouth – welding joint – pressing midsole – welding bottom – inspecting welding joint welding bottom – midsole spot welding getter – vacuuming – temperature measurement – electrolysis – polishing – temperature measurement – inspection and polishing – pressing outsole – spray painting – Temperature detection – spray paint inspection – silk screen printing – packaging – finished product storage