two controlled values · two controlled divisors · arithmetic comparison only

Controlled Strength-Ratio Comparison Worksheet

Divide two documented strength values by two documented divisors, compare the quotients and convert MPa/ksi. The worksheet does not select material properties, design factors or ASME allowable stress.

blank strict inputsMPa ↔ ksinot a code-allowable-stress formula

Not an ASME stress-table lookup, material selector, fatigue model or acceptance calculation. For ASME construction, obtain the applicable stress value from the current BPVC Section II Part D table/database and apply the governing construction Section, edition, addenda, Code Cases and jurisdictional requirements.

Controlled values, divisors and traceability

Controlled strength value Arequired positive plain decimal

Documented divisor nArequired plain decimal, at least 1

Controlled strength value Brequired positive plain decimal

Documented divisor nBrequired plain decimal, at least 1

Result display unit

Calculation record ID

Exact material specification, grade and edition

Product form, specification class and heat treatment

Thickness/diameter range and dimensional basis

Design/test temperature and unit

Governing construction code, edition, addenda and Code Cases

Value A source, table/column or controlled calculation

Divisor nA source and exact applicability condition

Value B source, table/column or controlled calculation

Divisor nB source and exact applicability condition

Material certificate, heat and test record

Jurisdiction, contract and acceptance basis

Responsible engineer / reviewer

Review date

Notes and exclusionsOptional: creep, time-dependent properties, weld joint, corrosion, cyclic service, instability, impact/toughness and load combinations.

Both strength values and divisors are copied from controlled sources applicable to the same material specification, product form, dimensions, condition and temperature.
If ASME construction applies, the actual allowable stress and required properties were obtained from the current BPVC Section II Part D stress table/database and governing construction Section—not generated by this worksheet.
Fatigue, impact/toughness, creep, buckling, weld/joint efficiency, corrosion, cyclic service, load combinations and other failure modes are outside this arithmetic comparison unless handled in separate controlled records.
The lower quotient will not be called an allowable stress, design stress or acceptance limit unless the governing current code explicitly defines that complete procedure for this exact case.

Arithmetic comparison

Lower quotient

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Lower arithmetic basis

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Quotient A = SA / nA

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Quotient B = SB / nB

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Normalized inputs

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Quotient separation

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Equations, units and classification

qA = SA / nA
qB = SB / nB
qmin = min(qA, qB)
1 ksi = 6.894 757 293 168 361 MPa

Quantity	একক	Meaning and boundary
SA, SB	MPa or ksi	user-supplied controlled strength-like values; this worksheet does not identify Rp0.2, Rm, S, Sm or another code property
nA, nB	dimensionless, ≥1	user-supplied divisors whose source and applicability must be documented; no safety factor is selected here
qA, qB, qmin	same stress unit	arithmetic quotients and their numerical minimum only; not automatically an allowable/design stress

Dividing a stress by a dimensionless number preserves stress units. The comparison is general arithmetic and is না presented as a formula from ASME BPVC, ISO 6892-1 or any other construction standard.

Removed unsafe claims

No invented steel-property database. The old page assigned one yield strength, tensile strength, elongation, hardness and density to each grade/condition without controlling product form, dimensions, heat treatment, temperature or material specification edition.
No universal ASME allowable-stress formula. The old code used min(Rp0.2/1.5, Rm/3.5) or Rm/2.4. ASME’s official resource identifies the BPVC Section II Part D stress-table database as the online version of the Code tables; the applicable table value and construction rules cannot be replaced by the old shortcut.
No fabricated fatigue endurance limit. The 0.5Rm/700 MPa rule, universal pulsating/reversed factors and impact factors were removed. Fatigue depends on the governing method, stress definition, cycles, geometry, surface, size, mean stress, environment, temperature, material data and modification factors.
No grade/condition presets. “Normalized”, “as-delivered” and “quenched and tempered” are not interchangeable property records across thicknesses and specifications.
No false room-temperature sufficiency. ASME material stresses and properties are selected for the exact material listing, product form, limits and design temperature; creep/time-dependent and other regimes require their governing rules.
No hidden state. Defaults, presets, automatic calculation, URL parameters, local history, clipboard output, dynamic HTML and external KaTeX were removed.

Source traceability

Claim	শ্রেণীবিভাগ	Evidence
The current ASME BPVC edition is 2025. ASME lists both BPVC Section II Part D—Properties (Customary and Metric) and Section VIII Division 1 in the 2025 edition.	Official ASME edition catalogue	2025 ASME BPVC
ASME’s BPVC Resources page states that the ASME BPVC Stress Tables database is the online version of the tables in Section II Part D—Properties, in customary and metric units.	Official ASME workflow; table values not reproduced	ASME BPVC Resources
BPVC Section VIII Division 1:2025 covers design, fabrication, inspection, testing and certification of pressure vessels under its scope, with specific requirements for materials and fabrication methods. A two-number shortcut is not a complete construction-code application.	Official ASME edition and scope	ASME BPVC VIII.1:2025
ISO 6892-1:2019 Edition 3, confirmed in 2025, specifies room-temperature tensile testing of metallic materials and defines mechanical properties obtainable by that test. It is not an allowable-stress design code.	Official ISO status and scope	ISO 6892-1:2019
NIST conversion guidance gives 1 ksi = 6.894757 MPa at its published precision; the worksheet carries the definition-derived factor 6.894757293168361 for round-trip numerical stability.	Official NIST unit conversion	NIST SP 811 Appendix B.9

Accessed: 15 July 2026. Exact ASME stress tables, bases for allowable stresses, material rows, temperature interpolation/rounding, notes, Code Cases and construction-Section rules remain NEEDS_LICENSED_SOURCE.

Reference check

For SA = 355 MPa, nA = 1.5, SB = 510 MPa and nB = 3.5, qA = 236.666666667 MPa, qB = 145.714285714 MPa and the lower arithmetic basis is B. This is deliberately not labelled an ASME allowable stress.

Questions

Why can I no longer select a steel grade?

A grade name alone does not determine design strength. Product specification, form, thickness, condition, temperature, certificate and governing code table/notes all matter.

Where do I get an ASME allowable stress?

Use the current licensed BPVC Section II Part D stress table/database for the exact material listing and temperature, then apply the governing construction Section, notes, Code Cases and jurisdictional requirements.

Does the lower quotient prove safety?

No. It is only the smaller of two divisions. The governing code must establish the properties, factors, failure modes, load combinations, geometry equations, examination and acceptance requirements.