Stainless Steel Thermos Flask Problems

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Stainless Steel Thermos Flask Problems

A stainless steel thermos flask is the best water bottle that can keep water ice cold to drink for a whole long and hot day. It is made from the stainless steel 18-8 (SUS304), which is highly resistant to rust and does not need a liner. This water bottle, non-toxic, BPA free, reusable, eco-friendly, complies with California Prop 65 regulations and Title 21 of the FDA Code of Federal Regulations.

But what problems can occur when using stainless steel thermos flask in our daily drinking? Let’s see what people complain when they are using the flask:

1. Rust corrosion inside of the metal bottle

2.Easy to get dents on the flask

3.Bottle cap is plastic rather than stainless steel

4.Too much heavy

5.Not that easy to clean



01.Rust Corrosion on the Stainless Steel Thermos Flask

It’s easy to get rust inside of the stainless steel water bottle, especially when you forget to wash it after drinking milk or juice. And after a couple of nights, you will find there’s terrible rust inside of the bottle. But don’t be worry, you can use white vinegar to remove the rust easily, following the steps of how to clean stainless steel water bottle to remove rust inside of the bottle.

Dent On Stainless Steel thermos flask bottle


02. Easy to Get Dents

It can’t avoid the dent on your stainless steel thermos flask. The dent may appear at home, at camping, or on the trip when you carelessly drop the bottle on the hard ground and thereby get one on the body, and it is possible to let your thermos flask stop working, that’s why it can not keep your water ice cold and easy to get warm.


03. The Bottle Cap Is Plastic Rather Than Stainless Steel

Although most of the stainless steel thermos flask brands claim that their bottles are reusable and made from recyclable stainless steel material, but most of them actually still use plastic material to make their bottle caps, why is that?


1.Plastic material doesn’t mean toxic or unsafe for hydration. The two kinds of plastic material “polypropylene,PP” and “Eastman Tritan” are both BPA free and comply with FDA/LFGB. They are widely used for tableware, baby feeding bottles, kitchenware and sports water bottle. You can use the plastic cap for your stainless steel bottle carefreely.

2. Plastic cap is technically easy to make. Stainless steel cap can be achieved for simple and regular round shape design, but it can not be made into complex designs such as a bottle cap and a lid with a straw.  That’s the reason why most of the bottle caps in the market is plastic made.

3.Plastic cap costs less. Because the plastic cap is easier to be produced, the cost is then cheaper to make a plastic cap than a stainless steel one in the same design.

4.Better performance of “no leaking, heat retention and screwing smoothness”.  It’s easy to guarantee the leaking proof for a plastic lid. And you can screw the plastic bottle cap or screw it off easily. The plastic cap also has better heat retention as the stainless steel has better “thermal conductivity”.

Anyway, we like the stainless steel thermos flask due to its stainless steel material. And we do not exclude the adoption of the plastic cap as is also eco-friendly and harmless to human health.



04.Too Much Heavy

When compared with a plastic water bottle, the stainless steel thermos flask is too much heavy. A thermos flask usually weighs from 200g to 400g, but a reusable plastic water bottle usually weighs from only 50g to 100g. Therefore, with help of numbers, we can see clearly that the thermos bottle is too much heavy. And that’s also one of the reasons why the metal bottle is much more likely to drop to the floor accidentally.


05.Not That Easy to Clean

When you wash the plastic water bottle, it is easy to see if you have cleaned it completely as the body is transparent. But for the stainless steel thermos flask, which is not transparent, requires you to pay more attention to the inner hygiene of it and wash the inside of the flask carefully.

It is also easy to scratch the surface of the stainless steel flask. Therefore, you should wash the bottle by hand with soft bottle brush or a soap.  But it is not a problem to wash it with dishwasher when your thermos flask is stainless steel color or powder coating color as these two colors won’t have discolor or painting off problem with dishwasher. Other colors, however, is better to wash by hand only.

Although there are some problems with the stainless steel thermos flask, we still love it as it is reusable, eco-friendly, food grade safe, and is the best option for keeping our water ice cold for 24 hours in hot Summer day. More information you want to know for the stainless steel thermos bottle products that how it works, how it is made, how much it cost to make, you can reach a manufacturer supplier like “Ecoshine Drinkware Limited” to get instant technique supports.

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