A drawing specifies one grade. A quotation names another and calls it equivalent. Purchasing does not choose the alloy; that belongs to the technical function. The buying decision is whether the proposed casting meets the drawing, the heat-treatment requirement and the test regime you are paying for.
This checklist covers cast steel grade equivalents: what to put in the RFQ, what to check on a mill or material test report, and what to verify before an equivalence claim is accepted for a cone or jaw liner, an HSI blow bar or a VSI wear part. For alloy selection itself, use our guide to crusher wear parts materials.
Why “Equivalent” Is a Purchasing Claim
Different standards describe similar steel and iron families with their own chemistry limits, property minimums, heat treatment and test methods. Two grades can share a hardness range or tensile target and still differ in carbon, alloy content, toughness or inspection.
An equivalence statement is a claim to verify, not a synonym to accept. The cost of a wrong claim rises with duty severity and casting size. A manganese cone liner or a high-chrome blow bar is not a place to discover a missing test requirement after the first failure.
What the RFQ Needs to Say
The RFQ and its specification sheet define what equivalence will be judged against. A grade name alone lets a supplier meet the name and miss the condition, test or section property that matters. Put these five items in writing.
| RFQ item | What to state | Why it matters |
|---|---|---|
| Part, drawing and duty | Part name, crusher type and size, reduction stage, feed size, mounting position, annual volume; drawing reference and revision, critical dimensions and wear-face datum | Prevents a wrong-duty profile or an obsolete drawing |
| Grade and condition | Original standard and grade, heat-treatment condition, mandatory and open callouts; for a proprietary designation, chemistry and property requirements in words | A grade label is not a specification |
| Chemistry | Element ranges, phosphorus and sulfur limits, residuals, and any element the supplier intends to vary | A generic chemistry can meet the name but not the part |
| Tests | Tensile, yield, elongation, reduction of area, hardness scale and location, specimen source, impact test where required | Properties from an unrepresentative specimen prove little |
| Reports and change control | Chemistry, mechanical, heat-treatment, dimensional and examination records; heat or lot identity; first-article approval; deviation list | Untraceable documents or a silent substitution |
Three callouts buyers leave vague
Drawing revision. A wear profile can change while the grade stays the same. Quote the revision you will inspect against.
Specimen location. A separately cast test bar that cools faster than a thick liner section does not represent that section. State whether the specimen must be attached.
Deviation list. Ask for every element, property, test and condition that differs. A summary that says “equivalent” is not a deviation list.
What to Verify on a Mill or Material Test Report
The mill or material test report is the first document to check, and the easiest place for a generic grade name to hide a shortfall. Read it against the RFQ, not a supplier summary.
| Check | What good looks like | Red flag |
|---|---|---|
| Heat or lot identity | Identifies the heat or lot in your castings and matches the marking and packing list | A grade-only report |
| Chemistry | Measured values for every specified element, including phosphorus, sulfur and residuals | “Typical” values, missing elements, or an over-wide range |
| Supplied condition | States the required condition: normalized, annealed, quenched and tempered, solution treated or stress relieved | Condition omitted or different from the drawing |
| Specimen source | Location stated and matches the agreed plan | No location, or a separately cast bar used for a heavy section |
| Scope | Covers your heat or lot, with all pages and signature | A different heat, missing page or unsigned copy |
What to Verify on Mechanical and Heat-Treatment Records
Chemistry alone does not establish equivalence. The mechanical and heat-treatment records must show the properties required by the drawing and how they were obtained.
- Results against minimums. Read actual values, including elongation and reduction of area, not only a pass stamp.
- Hardness. Confirm the scale and location. On a manganese liner, pre-service hardness is not work-hardened hardness; on a high-chrome blow bar, a traverse can show section variation.
- Heat-treatment record. Check temperature, holding time, cooling method and the condition supplied. The same chemistry given a different cycle can behave differently.
- Examination records. If the drawing requires non-destructive examination, confirm method, coverage, acceptance criteria and the operator record.
Cross-Reference Traps Specific to Wear Castings
Austenitic manganese steel and high-chromium white iron are the two families where grade names travel worst. Both appear in cone and jaw liners, HSI blow bars and VSI wear parts, and both are often quoted by a name that means something different elsewhere.
| Family | Typical specification basis | Common wear parts | Cross-reference risk |
|---|---|---|---|
| Austenitic manganese steel | About 1.0-1.4% carbon, 11-14% manganese; alloying varies by grade | Cone and jaw liners, blow bars, VSI wear parts | Work-hardening depends on impact; higher manganese is not automatically better |
| High-chromium white iron | About 12-28% chromium and 2-4% carbon, sometimes with molybdenum, copper or nickel | HSI blow bars, VSI wear parts, some liner and wear plates | Hardness can match while carbide structure and toughness differ |
| Martensitic and low-alloy cast steel | Medium-carbon, alloy steel; hardness set by heat treatment | Blow bars, jaw plates, wear plates | A close name can hide a different hardness and toughness balance |
| Carbon or low-alloy structural cast steel | Strength grade plus an impact requirement at a stated temperature | Frames, housings, non-wear components | Impact temperature, section size and heat treatment are often omitted |
A carbon or low-alloy frame casting may cross-reference more closely, but elongation, hardness and test frequency can still differ. A non-wear grade does not make the report optional.
Compare chemistry, condition, properties and test method together. A shared hardness number or a similar name is not enough.
How to Approve or Reject a Proposed Equivalent
Ask for a written deviation list: every element, property, test and heat-treatment condition where the proposal differs. Review it against the RFQ, not a supplier’s summary.
For a first article, check the mill report, mechanical report and measured dimensions together. If the failure mode is cracking, add a limited field trial under the same duty and track wear, breakage and fit. Approve the change through the technical function and record the deviation for the next order.
If a required report is missing or does not trace to the lot, treat it as a nonconformance. Do not let a production deadline turn a documentation gap into an accepted equivalence. Our crusher parts quality documents checklist covers the document set in more detail.
FAQ
Is a grade equivalent the same as a material substitution approval?
No. An equivalence claim compares specifications on paper. A substitution approval accepts a specific change for a part and duty, after the documents and, where needed, a trial are reviewed.
What is the first thing to check on a mill test report?
Traceability. Confirm it identifies the heat or lot used for your castings and the supplied condition, then compare measured chemistry with the specification.
Can a supplier meet the grade and still supply a poor cone liner?
Yes. Chemistry within the grade does not establish soundness, section properties or correct heat treatment. That is why the RFQ should require inspection records and, for critical parts, a first article.
Do I need impact testing on every HSI blow bar?
It depends on duty and failure mode. A bar that fails by cracking may need impact or toughness evidence; one that wears gradually may not. State the requirement in the RFQ.
How do I compare two quotes that name different grades?
Ask both suppliers to quote against the same specification and list deviations element by element. Compare chemistry, condition, reports and commercial terms, not grade names alone.
Request a Quote for Your Casting Project
Send your drawing, grade, heat-treatment requirement, test regime and annual volume through our contact page to request a quotation. Our team will review the specification and the reports we can supply. For help matching a grade to HSI or VSI duty, read our guide to HSI and VSI wear-part material selection; for the manganese family, read our guide to austenitic manganese steel crusher wear parts, or browse cone crusher liners.
