What This Part Is And Why It Is Made This Way
Large steel structural castings carry the main load path of a machine, which means a single internal defect can take the whole assembly out of service. These parts are produced in sand casting or shell moulding routes from grades such as G20Mn5, 42CrMo4 and G18NiMoCr3-6, in weights from 50 kg up to 20 tonnes.
Because the part is expensive to replace, the inspection plan is agreed before the mould is made: melting route, heat treatment, NDT scope and the certificates that travel with the part.
What You Get From This Route
One casting replaces a welded fabrication, removing weld seams as a fatigue starting point.
EAF + LF + VD / AOD melting routes give control over cleanliness on heavy sections.
Per part certificates and traceable quality documents support incoming inspection at the destination.
Application Scenarios
- Mining crushing and grinding equipment frames
- Cement mill and kiln support structures
- Construction machinery load bearing bodies
- Energy equipment structural housings
Who It Is For
- Equipment builders replacing heavy welded fabrications with a single casting
- Buyers who need NDT and material certificates before goods are accepted
- Maintenance teams sourcing replacement structures for installed machines
Technical Features
- Sand casting and shell moulding routes
- Zero draft sand casting reaches CT9 on automated lines
- Automated heat treatment line
- UT, MT and PT inspection by certified operators
What Buyers Run Into Without This Specification
- Heavy sections solidify slowly and trap porosity that only UT will find.
- A welded substitute cracks at the seam after a few thousand load cycles.
- Certificates arrive after the goods and hold up incoming inspection.
Published Material Weight And Process Data
Figures below are the published capability for steel castings and forgings. Part specific values — tolerance on individual features, finish, packing — are confirmed at drawing review and marked TBC until then.
| Material | 42CrMo4, G20Mn5, G26CrMo4, G18NiMoCr3-6, G22CrNi2Mo5-6, AISI 4340, AISI 4140, AISI 4325 and similar grades |
|---|---|
| Weight Range | Steel casting 50 kg - 20 T; forging 50 kg - 50 T |
| Process | Sand casting; shell moulding; open-die and closed-die forging; roll forging |
| Melting | High automation production lines with EAF + LF + VD / AOD melting routes |
| Tolerance | Zero draft sand casting to CT9 on automated heat treatment lines |
| Inspection | NDT with certified operators, single part certificates and quality document traceability |
| Part Specific Tolerance | TBC — confirmed against the customer drawing |
| Minimum Order Quantity | TBC — depends on the process route selected |
| Lead Time | TBC — confirmed with the production base at quotation |
How The Part Is Made And Checked
- Production — Highly automated production lines with EAF + LF + VD / AOD melting equipment.
- Quality — Certified NDT capability, supporting per-part certificates and traceable quality documents.
- Process Control — Automated heat treatment lines; zero draft sand casting reaches CT9.
Quality management is based on ISO 9001 and covers supplier management, raw material inspection, production process control and final inspection. Inspection results are archived and traceable.
Options And Alternatives
Parts are produced to the customer drawing rather than to a fixed catalogue item, so material grade, machining scope, surface treatment and packing are all specified per order. Machining, dimensional control, surface treatment and necessary pre-assembly can be added to the same supply route.
Where another process family would suit the part better — for example a forging in place of a casting for a shock loaded connector — that comparison is raised during drawing review rather than after tooling is committed.
How To Specify This Part
Send the drawing together with the load case and the acceptance standard. The critical decision on a part this size is the NDT class and the zone map — which areas are inspected to which level — because that fixes the casting method, the feeding design and the price far more than the raw weight does.
- Send the drawing with material, quantity, quality standard and target delivery date.
- State the inspection class and the zones it applies to, rather than a general note.
- Confirm the packing requirement and the lifting equipment available at the destination.
Related Guides
Other Parts In This Range
Slewing Support Structural Castings
Rotating support bodies with machined bearing seats
View specifications
Forged Shafts
Stepped shafts with continuous grain flow
View specifications
Flanges and Sleeve Components
Connection flanges and sleeve bodies
View specifications
Large Gear Rings
Cast and forged ring gears for heavy drives
View specificationsLarge Steel Structural Castings — Frequently Asked Questions
What is the largest steel casting you can supply?
Steel castings are supplied from 50 kg up to 20 tonnes. Forgings in the same business run from 50 kg up to 50 tonnes.
Can you supply material certificates for each part?
Yes. The production base supports single part certificates and traceable quality documents, and the NDT scope is agreed before production starts.
What do you need to prepare a quotation?
Drawings, material, quantity, quality standard and target delivery date.
Which inspection is included?
The inspection scope is agreed during drawing review. Automated heat treatment lines; zero draft sand casting reaches CT9.
Get A Quotation For Large Steel Structural Castings
Send the drawing and the application. We will confirm the process route, the production base and the inspection scope before quoting.