Views: 0 Author: Site Editor Publish Time: 2026-08-24 Origin: Site
A sheet metal enclosure can look perfect before welding.
The panels are cut correctly.
The bends are formed.
The dimensions appear to be within the expected range.
Then the enclosure is welded.
After welding, something changes.
A panel is no longer perfectly flat.
A door does not align as expected.
A mounting hole appears slightly out of position.
A large enclosure seems to have twisted.
This can be confusing for buyers.
The question is often:
If the individual sheet metal parts were made correctly, why did the assembled enclosure change shape?
The answer is usually related to the welding process and the way heat affects the metal structure.
Welding is not simply joining two pieces together.
Heat is introduced into specific areas of the structure, and that heat can cause localized expansion and contraction.
For a custom metal enclosure, understanding this before production can help both the buyer and manufacturer make better design decisions.
When metal is welded, the area around the weld becomes very hot.
As the material heats up, it expands.
When it cools, it contracts.
If the heating and cooling are not evenly distributed throughout the structure, the contraction can pull the surrounding material.
This can result in:
Panel distortion
Warping
Twisting
Misalignment
Changes in flatness
The larger and thinner the panel, the more noticeable this can become.
This is why a large flat sheet can require more attention during welding than a small reinforced component.
Imagine two enclosure designs.
A small panel with several bends and reinforcement features.
A large flat sheet with minimal structural support.
Both may use the same material thickness.
But Design B may be more sensitive to deformation during welding.
Why?
Because a large unsupported surface has more freedom to move when welding heat is introduced.
This does not mean large flat panels cannot be manufactured.
It means the structure may need to be designed with manufacturing behavior in mind.
Depending on the product, this can involve:
Bends
Reinforcement structures
Internal supports
Different joint arrangements
The enclosure should be designed as a complete structure rather than treating every panel as an isolated piece.
More welding does not automatically mean a stronger or better enclosure.
A design may contain long continuous welds along several edges.
This can introduce a significant amount of heat into the structure.
Depending on the design, shorter or strategically arranged welds may sometimes reduce unnecessary heat input while still providing the required structural connection.
The correct approach depends on:
Structural requirements
Panel geometry
Material
Thickness
Joint design
Product application
For this reason, welding should be considered during the enclosure design stage.
Not simply added after the sheet metal structure has already been finalized.
The order in which different sections are welded can affect the final shape.
Consider an enclosure frame with several connected panels.
If one side is welded continuously before the opposite side is joined, the resulting heat and contraction may pull the structure in one direction.
A different welding sequence may distribute the effect differently.
This is why experienced manufacturers do not necessarily approach every welded enclosure in exactly the same way.
The production team may need to consider:
Where to weld first
Where to weld next
How the structure is supported
When to allow the part to cool
How the assembly is positioned during welding
For complex ODM projects, these manufacturing considerations can be discussed before the design enters production.
A 1.0 mm sheet and a 2.0 mm sheet do not necessarily behave the same way during welding.
Thinner material can be more sensitive to localized heat.
At the same time, increasing thickness is not automatically the correct solution.
The better approach is to consider the complete structure:
Material + thickness + joint design + welding method + enclosure geometry
For example, if a panel needs additional stiffness, the solution may involve structural design rather than simply increasing the thickness everywhere.
This can help balance:
Weight
Material cost
Strength
Manufacturing requirements
For an ODM enclosure, this is one area where structural optimization can create practical value.
The way two panels meet can affect the welding process.
A joint may be:
Easy to access
Difficult to access
Suitable for consistent welding
Difficult to position
More sensitive to visible deformation
This is particularly important for customer-facing products.
For example, if a visible front panel requires welding along a large surface, the final appearance may become more difficult to control if the structure is not designed appropriately.
A better approach is to consider:
How will these two parts actually be positioned, fixed, welded, and finished?
before the design is finalized.
This is one reason manufacturing review is valuable during ODM development.
One of the easiest mistakes is to evaluate every individual part separately.
The laser-cut panel looks correct.
The bent panel looks correct.
The mounting bracket looks correct.
But after welding everything together, the final enclosure may not behave exactly as expected.
The reason is that manufacturing processes interact.
For example:
Laser cutting → Bending → Positioning → Welding → Grinding → Powder Coating → Assembly
Each stage can influence the next stage.
A successful enclosure therefore needs to be evaluated as a complete manufacturing system.
A small amount of deformation may not matter for every product.
But it can become important when the enclosure contains:
Large doors
Display openings
Multiple mounting interfaces
Precision component locations
Sealing requirements
Panels that must align visually
For example, a door may still physically close after a small structural change.
But if the gap around the door becomes inconsistent, the finished product may not meet the expected appearance or sealing requirements.
This is why the acceptable amount of deformation depends on the actual product requirement.
This is an important distinction.
A buyer may see a slight deformation and immediately conclude:
The manufacturer made a mistake.
But the actual issue may have started much earlier.
For example:
The enclosure has a very large unsupported panel.
The design requires long continuous welds.
The material is very thin.
The joint structure concentrates heat in one area.
No allowance was made for the manufacturing process.
In these situations, the problem may be partly related to product design.
This is why ODM support can be useful.
Instead of asking only:
Can you manufacture this drawing?
the better question can be:
Can this design be manufactured reliably at the required production volume?
There is no single solution for every enclosure.
However, several design and manufacturing principles can help.
Where appropriate, structural features can improve panel stiffness.
Consider whether long continuous welds are actually necessary.
Tell the manufacturer which areas must remain visually consistent or dimensionally controlled.
Think about how the enclosure will be positioned and assembled before welding.
Do not evaluate each sheet metal component independently.
A prototype can reveal practical behavior before larger production quantities.
Consider a large outdoor EV charger enclosure.
It may contain:
Front door
Internal mounting plate
Electrical components
Cable entry areas
Side panels
Rear structure
The front door may be one of the most visible parts of the product.
If welding causes excessive deformation in the surrounding frame, it may affect:
Door alignment
Door gaps
Appearance
Sealing structure
The solution may not simply be:
Weld more carefully.
The design itself may need to be reviewed.
This is where manufacturing experience can become part of the product development process.
Industrial equipment housings can also contain large welded structures.
For example:
A machine enclosure may use multiple panels joined around a structural frame.
If the frame changes shape during welding, later assembly may become more difficult.
The issue may then appear as:
Why don't the panels line up?
But the root cause may have started during the welded frame stage.
This demonstrates why process planning matters.
If you are developing a welded metal enclosure, provide information about:
Critical dimensions
Critical mounting positions
Customer-facing surfaces
Door alignment requirements
Sealing requirements
Internal component locations
Expected production quantity
Also tell the manufacturer if certain areas are especially important.
For example:
The front door gap must remain visually consistent around the entire perimeter.
Or:
The internal mounting holes must align with the power module.
This allows the manufacturer to understand what should receive the most attention.
The best time is before production.
During the design review, ask:
Are there any areas of this enclosure that may be sensitive to welding distortion?
This simple question can start a useful engineering discussion.
It may lead to changes in:
Panel structure
Joint design
Reinforcement
Welding locations
Assembly sequence
Making a small change during the design stage is usually easier than correcting a structural problem after production.
Before approving a custom welded enclosure, review:
Are there large unsupported flat surfaces?
Can the joints be manufactured and welded consistently?
Are long continuous welds actually necessary?
Which dimensions must remain controlled after welding?
Which surfaces are highly visible?
Are door gaps and opening positions important?
Will the welded structure still allow the remaining components to be installed?
Will the design remain practical when moving from prototype to repeated production?
In a traditional manufacturing relationship, the buyer may provide a finished drawing and expect the factory to produce exactly what is shown.
In an ODM project, the relationship can be different.
The manufacturer can participate earlier in the process.
For example:
Product concept
↓
Structural development
↓
Manufacturing review
↓
Prototype
↓
Design adjustment
↓
Production
This can allow manufacturing considerations to influence the enclosure before the design is locked.
For welded sheet metal products, that can be particularly valuable because the final behavior depends on both the design and the manufacturing process.
Welding distortion is not simply a question of whether a welder is skilled.
For a custom sheet metal enclosure, the final result can be influenced by:
Panel geometry
Material thickness
Joint design
Weld length
Welding sequence
Structural reinforcement
Assembly requirements
The most effective approach is to consider these factors before production begins.
A good enclosure design should not only look correct in CAD.
It should also be capable of being manufactured repeatedly with the required structural and appearance results.
That is especially important when moving from prototype quantities to regular production.
Welding introduces localized heat. As the heated metal expands and then contracts during cooling, the surrounding structure can deform.
They can be more sensitive to localized heat, particularly when the panel is large and has limited structural support.
Manufacturing processes can be planned to reduce distortion, but the actual result depends on the material, geometry, thickness, joint design, and welding requirements.
Not necessarily. Additional welding can introduce more heat and may increase manufacturing complexity. Weld locations and structural design should be considered together.
Yes. Reviewing welding and structural requirements early can help identify potential manufacturing issues before prototype or mass production.
If your enclosure contains large panels, welded frames, doors, internal mounting structures, or critical alignment requirements, these factors should be considered before production.
Send us your drawing or product concept. Our ODM team can review the enclosure structure and manufacturing requirements before the design moves into production.
