Overview
A stainless steel insulated bottle is built through a series of forming, welding, vacuum, surface treatment, assembly, and inspection processes. The exact manufacturing route depends on how the bottle body is initially formed.
Based on the production process, there are two main routes:
l Tube-Based Process
Tube Manufacturing → Hydroforming → Metalworking → Cup Welding → Vacuumization → Electrolysis → Polishing → Spray Coating → Assembly → Packaging → Final Inspection
l Deep-Drawing Process
Blanking → Deep Drawing → Metalworking → Cup Welding → Vacuumization → Electrolysis → Polishing → Spray Coating → Assembly → Packaging → Final Inspection
Two Main Bottle-Forming Methods
The main difference between the two manufacturing routes is how the stainless steel material is formed at the beginning of production.
Tube Forming
In the tube-based route, stainless steel is first made into tubes for the inner and outer shells. The tube is then shaped through hydroforming before moving to subsequent metalworking and welding processes. One visible characteristic of this route is the straight welding seam on the inner liner, which can be seen visually.
The basic route is:
Tube Manufacturing → Hydroforming → Metalworking
Round-Sheet Deep Drawing
In the deep-drawing route, the process starts with round stainless steel sheet blanks. The blanks are formed directly through deep drawing to create the required bottle components. Unlike the tube-based route, the resulting inner liner has no visible straight welding seam.
The basic route is:
Blanking → Deep Drawing → Metalworking
These two forming methods provide different starting points for the rest of the manufacturing process.
The Complete Manufacturing Flow
1. Tube Manufacturing or Blanking
The production route begins either with stainless steel tubes or with round sheet blanks. The choice depends on the forming method used for the bottle.
2. Hydroforming or Deep Drawing
The selected forming process creates the initial geometry of the bottle components. Hydroforming is used in the tube-based route, while deep drawing is used when the bottle starts from round stainless steel sheet.
3. Metalworking
After initial forming, the components undergo metalworking to achieve the required dimensions and geometry. This prepares the components for the following welding and assembly processes.
4. Cup Welding
The inner and outer components are joined through welding to create the double-wall bottle structure. This structure provides the enclosed space needed for the subsequent vacuumization process.
5. Vacuumization
After the bottle structure has been welded, air is removed from the interlayer between the inner and outer shells. The cavity is then sealed to establish the vacuum insulation layer. Vacuumization is a key stage in creating the thermal structure of an insulated bottle.
6. Electrolysis
The inner surface undergoes electrochemical treatment to refine its surface condition. This process is particularly relevant to the inner liner, where surface quality is an important part of the finished product.
7. Polishing
The external surface is polished according to the required appearance. Depending on the product specification, polishing can help create the required surface finish and prepare the bottle for subsequent treatment.
8. Spray Coating
The bottle receives its required exterior coating according to the product requirements. This is where the selected surface finish and color system are applied to the bottle exterior.
9. Assembly
After surface treatment, the bottle body is assembled with its corresponding components.
10. Packaging
The finished product is packaged according to the required packaging configuration.
11. Final Inspection
Before shipment, the completed products undergo final inspection to verify that they meet the required product and manufacturing specifications.
Why Are There Two Manufacturing Routes?
The two routes use different starting materials and forming methods:
Tube-Based Route
Tube → Hydroforming → Metalworking
Deep-Drawing Route
Round Sheet → Deep Drawing → Metalworking
The resulting inner liner appearance is also different:
· Tube forming: visible straight welding seam
· Deep drawing: no visible welding seam
The actual production route depends on the required bottle structure and manufacturing approach.
What Happens After the Bottle Body Is Formed?
Initial forming is only the beginning of the manufacturing process. After hydroforming or deep drawing, the components still need to be processed into a complete insulated bottle. Metalworking brings the formed components to the required dimensions, while welding creates the double-wall structure.
The bottle then enters vacuumization, where the interlayer is evacuated and sealed. After that, surface treatments such as electrolysis, polishing, and spray coating are carried out before assembly, packaging, and final inspection.
The overall manufacturing route can be understood as:
Forming → Metalworking → Welding → Vacuumization → Surface Treatment → Assembly → Packaging → Inspection
What Does This Mean for B2B Drinkware Development?
For brands and product developers, understanding the manufacturing route helps explain why two bottles with similar overall designs may be produced differently. A bottle developed from a tube and a bottle developed through deep drawing do not start from the same material form, and their inner liner appearance may also differ. For OEM and ODM projects, the forming route is therefore part of the product development process. The choice of manufacturing route needs to work together with the bottle structure and subsequent production requirements.
At Ansune, tube-based and deep-drawing routes are integrated with metalworking, welding, vacuumization, surface treatment, assembly, and final inspection to support the production of stainless steel insulated drinkware.