Key & Keyway Shear/Bearing Stress Calculator implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-clean

Evidence ID

t5-074

Effect

Computation or source lookup only

Input and validation requirements

The specification provides no safety-factor formula or allowable-strength input, so SF cannot be computed honestly. It also requires rejection of zero geometric dimensions; otherwise the stress formulas produce undefined division-by-zero results. Torque-sign handling is unspecified and can reverse both reported stresses.

Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "T": 100000,
    "T_unit": "N·mm",
    "d": 50,
    "w": 10,
    "h": 6,
    "L": 40,
    "length_unit": "mm"
  },
  "expected_outputs": {
    "tau_MPa": 10,
    "sigma_bearing_MPa": 33.3333333333,
    "SF": "undefined: no allowable-stress input or safety-factor formula"
  },
  "working": "τ = 2T/(d·w·L) = 2(100000)/(50·10·40) = 200000/20000 = 10 N/mm² = 10 MPa. σ_bearing = 4T/(d·h·L) = 4(100000)/(50·6·40) = 400000/12000 = 33.3333333333 N/mm² = 33.3333333333 MPa. SF cannot be calculated because no allowable stress or SF definition is supplied."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche5/tranche5-results.json