Sheet metal

Custom sheet metal fabrication

Sierxi fabricates electrical enclosures, equipment housings and energy-storage cabinets in Suzhou with in-house fiber laser cutting, CNC press brakes and laser welding. We cut sheets up to 1500 × 3000 mm and 20 mm thick, bend lengths up to 3 m, and build cabinets up to 3000 mm tall and 1500 mm wide.

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CNC press brakes in the Sierxi sheet metal workshop

Capabilities at a glance

Cutting	In-house fiber laser cutting
Max sheet size	1500 × 3000 mm
Max thickness	20 mm
Bending	CNC press brakes, up to 3 m
Welding	5 laser welders + conventional welding
Largest cabinet	3000 mm tall × 1500 mm wide
Finishing	Powder coating, painting, plating, brushing via partners

Sheet metal

Custom electrical enclosures

Control boxes, cabinets and automation-equipment housings.

Sheet metal

Energy-storage cabinet fabrication

Frames, doors, shelves and skins for battery cabinets.

Fiber laser cutting machine used for stainless steel sheet

Sheet metal

Stainless steel sheet metal fabrication

Laser cut, bent and laser welded stainless enclosures, panels and frames.

Sheet metal

Laser welding for stainless and steel parts

Low-distortion laser welding of enclosures, frames and stamped assemblies.

Sheet metal

Sheet metal prototypes and low-volume production

Tool-free prototypes and small batches, with a path to stamping.

From flat blank to finished cabinet

Blanks are cut on a fiber laser, formed on CNC press brakes and joined by laser or conventional welding. Inserts, studs and hardware are fitted in-house before parts go out for coating, then come back for final assembly and inspection.

What is done in-house and what by partners?

Step	Where
Fiber laser cutting	In-house
CNC bending (up to 3 m)	In-house
Laser welding (5 machines) and conventional welding	In-house
Hardware insertion and assembly	In-house
Inspection and dimensional report	In-house
Powder coating, painting, plating, brushing	Qualified finishing partners

Sheet metal design guidelines

These rules of thumb keep parts within tolerance and avoid extra cost. They are typical values for air bending of steel and aluminium; we check each drawing against the actual tooling before quoting.

Inside bend radius: about equal to material thickness (t) is a safe default; aluminium A5052 and thick stainless may need more
Minimum flange length: as a rule of thumb about 4 t, depending on the V-die used
Hole-to-bend distance: at least about 2 t plus the bend radius, or the hole distorts during bending
Laser-cut hole diameter: at least about the material thickness; smaller holes may need drilling
Bend relief: add a relief cut where a bend meets an edge, at least t wide and slightly deeper than the bend radius
Self-clinching nuts and studs: follow the fastener maker’s minimum sheet thickness and edge distance
Use one bend radius across the part where possible so it can be formed with one tool set
General tolerances: reference JIS B 0408 or ISO 2768 and tighten only critical dimensions

Which sheet material should I use?

Qualitative comparison. Other grades are quoted on request.
Material	Corrosion resistance	Weldability	Typical use
SPCC cold-rolled steel	Low — needs coating	Good	Indoor enclosures, painted or powder coated
SGCC galvanized steel	Moderate	Fair (zinc fumes at welds)	Mounting plates, internal frames, cabinets
SUS304 stainless steel	High	Good — suits laser welding	Food, outdoor and wash-down equipment
A5052 aluminium	Good	Fair — needs care	Light covers and housings

Laser welding or conventional welding?

Laser welding puts less heat into the part than MIG or TIG welding, so thin panels distort less and stainless seams need less grinding and polishing. It suits visible seams, thin sheet and precise assemblies. Conventional welding is still used for thick sections and structural frames where gap tolerance is larger. We choose the method per joint and show it on the process plan.

Prototypes and low volume

Laser cutting and bending need no hard tooling, so sheet metal is the right process for prototypes and runs of a few to a few hundred units. When a part moves to tens of thousands a year, we can review it for conversion to stamping.

Inspection and documents

We work under an ISO 9001:2015 quality system. First articles are measured against the drawing; production lots are inspected by AQL sampling. Small parts are measured on a vision measuring system, threads are checked with JIS 6H thread gauges, and a dimensional report can ship with each lot. Material certificates (mill test certificates) are supplied with every lot on request.

What to send with a sheet metal RFQ

3D model (STEP) and 2D drawing (PDF) with tolerances
Material grade and thickness
Finish: coating type, colour (for example a RAL code), texture and masked areas
Hardware list: nuts, studs, hinges, locks, gaskets
Quantity per order and per year
Destination country, for packing and freight

Shipping large parts

Cabinets and enclosures are bulky and dent easily, so packaging and freight are quoted per market. We do not promise one global lead time; tell us the destination and we will quote packing and freight with the parts.

Frequently asked questions

Is laser cutting done in-house?

Yes. Fiber laser cutting, CNC bending and laser welding are all done in our own workshop. Surface finishing is done by qualified partners.

What is the largest enclosure you can build?

Up to 3000 mm tall and 1500 mm wide, from sheets up to 1500 × 3000 mm.

Can you build one prototype?

Yes. Sheet metal needs no hard tooling, so we quote prototypes and small batches from your drawing.

What is the thickest sheet you can cut?

Up to 20 mm, on sheets up to 1500 × 3000 mm. Bending length is up to 3 m.

Which tolerance standard do you use?

Your drawing first. Where general tolerances are not stated, JIS B 0408 or ISO 2768 is agreed in the quote.

How are lead time and payment terms set?

Sample cost, lead time and payment terms are confirmed per project in the quote.

Sheet metal