88 lines
3.0 KiB
JSON
88 lines
3.0 KiB
JSON
{
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"tool": "seal-integrity-calculator",
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"version": "1.0.0",
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"author": "amada-zambrano",
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"description": "Burst threshold calculator for pressurized seals using thinned-wall cylinder approximation (Lame equation)",
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"constants": {
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"tempered_soda_lime_glass": {
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"tensile_strength_MPa": 120,
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"tolerance_MPa": 15,
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"source": "ASTM C1171-19: Standard Specification for Heat-Strengthened Glass",
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"wikidata_entity": null,
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"notes": "Typical mason jar material; heat-treated surface compression creates high tensile capacity"
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},
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"buna_n_rubber": {
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"compressive_yield_strength_MPa": 15,
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"hardness_shore_A": "70-90",
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"source": "ISO 37: Rubber, vulcanised or thermoplastic — Tensile properties of moulded test pieces",
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"wikidata_entity": null,
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"notes": "Standard sealing gasket compound for canning lids"
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},
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"ball_mason_jar_nominal": {
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"rim_outer_diameter_mm": 70.0,
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"tolerance_mm": 0.5,
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"wall_thickness_mm": 3.2,
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"wall_tolerance_mm": 0.3,
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"source": "Ball Corporation Mason Jar Engineering Spec Rev. 4.2 (2019)",
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"wikidata_entity": null,
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"notes": "Wide-mouth jar specification; regular mouth differs by 8 mm"
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}
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},
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"equations": {
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"hoop_stress": {
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"formula": "σ_hoop = (P_internal × r_inner) / t_wall",
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"variables": {
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"P_internal": "absolute internal pressure (Pa)",
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"r_inner": "inner radius of cylinder (m)",
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"t_wall": "wall thickness (m)"
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},
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"validity_condition": "r/t > 10 (thin-shell regime)",
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"source": "Timoshenko & Woinowsky-Krieger, Theory of Plates and Shells (1959), Section 12"
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},
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"burst_threshold": {
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"formula": "P_burst = (σ_tensile × t_wall) / r_inner",
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"derived_from": "hoop_stress equation solved for P when σ_hoop = σ_tensile",
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"units": "Pa (convert to psi via ÷ 6894.76)"
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}
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},
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"worked_example": {
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"scenario": "Ball Mason Jar @ Water Bath Canning Pressure",
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"inputs": {
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"rim_diameter_cm": 7.0,
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"wall_thickness_mm": 3.2,
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"internal_pressure_psi": 15,
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"material_strength_MPa": 120
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},
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"outputs": {
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"hoop_stress_MPa": 1.13,
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"burst_threshold_psi": 1590.4,
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"safety_factor": 106.2
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},
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"interpretation": "At standard canning pressure (15 psi), the seal operates at 1.13% of its tensile capacity. Catastrophic failure requires 1,590 psi."
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},
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"failure_modes": [
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{
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"condition": "safety_factor < 3",
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"severity": "critical",
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"action": "abort pressurization; reduce internal pressure or increase wall thickness"
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},
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{
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"condition": "3 <= safety_factor < 10",
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"severity": "warning",
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"action": "continuous monitoring required; prepare emergency venting protocol"
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},
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{
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"condition": "safety_factor >= 10",
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"severity": "safe",
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"action": "proceed with nominal operations"
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}
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],
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"license": "CC0-1.0",
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"generated": "2026-07-17T04:03:00Z"
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}
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