Spreader Beam Design Calculator report

Example project · Rev A

2026-08-06 00:19:15 UTC

SI (mm · kN · MPa)

Mechanics solve + ASME BTH-1 route

Inputs summary

Configuration

Spreader beam (two top slings)

Solve mode

Level lift (asserted attitude)

Rated load (WLL)

98.1 kN

Span

6000 mm

Section

CHS 273 × 12.7 (UNKNOWN)

$F_{y}, F_{u}$

Fy 355 MPa · Fu 490 MPa

BTH-1 basis

Design Category B, Service Class 0

Load CoG

x = 3000 mm, −500 mm below lift points

Schematic

Lift arrangement elevation: beam with 2 top slings to the hook and 2 bottom slings to the load, hanging level. Drawn to scale from the solved arrangement.

Governing summary

Governing check

Sling angle within declared limits

Utilisation

0.759 (75.9%)

Overall status

pass

FEA recommended

Checks

Check	Demand	Capacity	U	Status
Static determinacy of the lift arrangement	—	—	—	Pass
Arrangement is statically determinate — solved exactly.
Equilibrium tilt angle	0.00 deg	6.00 deg	0.000	Pass
Level-lift mode: the beam is asserted level; the solver placed the hook over x = 3000 mm and reports the sling lengths that realise it. Required top sling lengths: 5874 mm / 5874 mm.
Equations used $\sum M_{hook} = 0, \sum M_{CoG, load} = 0$ (Rigid-body equilibrium of the suspended assembly)
Sling tensions and angles	60.13 kN	—	—	Info
top-1: 60.1 kN at 30.7° from vertical; top-2: 60.1 kN at 30.7° from vertical; bottom-1: 49.3 kN at 0.0° from vertical; bottom-2: 49.3 kN at 0.0° from vertical. Slings, shackles, and hooks are rated proprietary gear — verify each against its manufacturer rating at the reported angle.
Sling angle within declared limits	59.29 deg from horizontal	45.00 deg minimum	0.759	Pass
Flattest sling: 59.3° to the horizontal; declared minimum 45°. DNV-ST-N001 §16.3.4.2 recommends ≥ 45° generally (informational here unless the DNV overlay is active).
Beam axial force and sense	30.71 kN compression	—	—	Info
Beam is in COMPRESSION (30.7 kN governing) — buckling-family checks apply.
Internal force envelope at critical sections	8.20 kN·m	—	—	Info
Max \|M\| = 8.20 kN·m at midspan; max \|V\| = 2.4 kN at top lug 1. Padeye eccentricity couples (H·e): -4.61 kN·m at x = 0 mm; 4.61 kN·m at x = 6000 mm; 0.00 kN·m at x = 0 mm — included in the moment diagram.
Equations used $M (x) = \int_{0}^{x} V d x, m_{pin} = H \cdot e$ (Piecewise-analytic beam statics with pin transfer couples)
Suspended-assembly roll stability (diagnostic)	500.00 mm CoG below lift points	—	—	Info
Load CoG sits 500 mm BELOW its lift points — the load hang is roll-stable in this plane. Diagnostic only — this is public-domain mechanics, not a code clause.
Deflection (serviceability)	2.07 mm	30.00 mm (L/200)	—	Info
Max sag 2.1 mm vs user limit 30.0 mm (ratio 0.07). Serviceability information — BTH-1 §3-5.3 places deflection limits with the qualified person.
Rigid-body solve validity screen	2.07 mm	30.00 mm (L/200 screen)	—	Pass
Deflections are small relative to the geometry — the rigid-body attitude solve holds.
Width–thickness classification — BTH-1 Table 3-2.2-1	—	—	—	Pass
CHS D/t = 23.1 on the §3-1.7 design wall — compact for flexure (limits 0.07·E/Fy = 39.4, 0.31·E/Fy = 174.6); fully effective for axial compression (0.11·E/Fy = 62.0).
Hollow-section design wall thickness — BTH-1 §3-1.7	—	—	—	Pass
Manufacturing method UNKNOWN: design wall = 0.93 × nominal = 11.81 mm (nominal 12.70 mm). All section properties in this route use the design wall — method unknown, so the smaller value governs as §3-1.7 directs.
Axial tension — BTH-1 §3-2.1	—	—	—	Info
No net axial tension at any critical section — the compression family governs this arrangement.
Axial compression — BTH-1 §3-2.2	3.17 MPa	85.56 MPa	0.037	Pass
Governs at top lug 1. Slenderness Kl/r = 64.9 about the weak (out-of-plane) axis (Cc = 105.5, inelastic eq. (3-3) branch).
Equations used $C_{c} = \frac{2 π ^{2} E}{F _{y}}, F_{a} = {eq. (3-3) \frac{π ^{2} E}{1.15 N _{d} ( K l / r ) ^{2}} K l / r < C_{c} K l / r \geq C_{c}$ (BTH-1 §3-2.2)
Major-axis bending incl. LTB — BTH-1 §3-2.3	13.52 MPa	130.17 MPa	0.104	Pass
Governs at midspan; allowable from eq. (3-6). Circular section — eq. (3-6)/(3-9) applies at any unbraced length; a CHS spreader has no lateral-torsional buckling check (§3-2.3.1).
Equations used $C_{L T B} = \frac{2.00 E I _{x} / ( G J )}{( L _{b} / b _{f} ) ^{2}} + 0.275 \leq 1.00$ (BTH-1 eqs. (3-16)/(3-17), ends not braced against twist)
Shear — BTH-1 §3-2.3.6	0.39 MPa	68.32 MPa	0.006	Pass
Governs at top lug 1 (tube shear area 2A/π; the plate h/t validity limit is not applicable).
Equations used $F_{v} = \frac{F _{y}}{N _{d} 3}$ (BTH-1 eq. (3-28))
Combined axial + bending — BTH-1 §3-2.4	0.14 interaction	1.00 limit	0.141	Pass
Governs at midspan via eq. (3-34) (cylindrical family; Cm = 1.0 per §3-2.4 unless justified by analysis).
Equations used $\frac{f _{a}}{F _{a}} + \frac{C _{m} f _{b}}{( 1 - \frac{f _{a}}{F _{e}^{'}} ) F _{b}} \leq 1.0$ (BTH-1 eqs. (3-32)–(3-34)/(3-36))
Combined normal + shear — BTH-1 §3-2.5	16.69 MPa	118.33 MPa	0.141	Pass
Governs at midspan. Peak normal and peak shear stress are conservatively combined at the same point (they occur at different fibres of the section).
Equations used $f_{cr} = f_{x}^{2} - f_{x} f_{y} + f_{y}^{2} + 3 f_{v}^{2} \leq \frac{F _{y}}{N _{d}}$ (BTH-1 eq. (3-37))
Connection eccentricity accounted for — BTH-1 §3-3.1	—	—	—	Pass
Per-pin eccentricity ledger (offset e from the centroidal axis, horizontal component H, transfer couple H·e — all included in the moment diagram): x = 0 mm: e = 150 mm, H = 30.7 kN, H·e = 4.61 kN·m; x = 6000 mm: e = 150 mm, H = -30.7 kN, H·e = 4.61 kN·m; x = 0 mm: e = -150 mm, H = 0.0 kN, H·e = 0.00 kN·m; x = 6000 mm: e = -150 mm, H = 0.0 kN, H·e = 0.00 kN·m.
Fatigue — BTH-1 §3-4	—	—	—	Pass
Service Class 0 (up to 20 000 load cycles) — fatigue analysis is not required per §3-1.4.
Padeye pinhole tension — BTH-1 §3-3.3.1	60.13 kN	239.25 kN	0.251	Pass
Governs at the top-1 pin (x = 0 mm) (highest pin force).
Equations used $P_{t} = C_{r} \frac{F _{u}}{1.20 N _{d}} 2 t b_{e f f}$ (BTH-1 eq. (3-45))
Padeye single-plane fracture — BTH-1 §3-3.3.1	60.13 kN	268.63 kN	0.224	Pass
Governs at the top-1 pin (x = 0 mm) (highest pin force).
Equations used $P_{b} = C_{r} \frac{F _{u}}{1.20 N _{d}} [1.13 (R - \frac{D _{h}}{2}) + \frac{0.92 b _{e}}{1 + b _{e} / D _{h}}] t$ (BTH-1 eq. (3-49))
Padeye double-plane shear-out — BTH-1 §3-3.3.1	60.13 kN	281.53 kN	0.214	Pass
Governs at the top-1 pin (x = 0 mm) (highest pin force).
Equations used $P_{v} = \frac{0.70 F _{u}}{1.20 N _{d}} A_{v}, A_{v} = 2 [a + \frac{D _{p}}{2} (1 - cos ϕ)] t$ (BTH-1 eqs. (3-50)/(3-51))
Padeye pin bearing — BTH-1 §3-3.3.4	60.13 kN	118.33 kN	0.508	Pass
Governs at the top-1 pin (x = 0 mm) (highest pin force). Service Class 0 — static coefficient 1.25 (eq. 3-53).
Equations used $F_{p} = \frac{1.25 F _{y}}{N _{d}} (static); \frac{0.63 F _{y}}{N _{d}} (rotating)$ (BTH-1 eqs. (3-53)/(3-54), projected area Dp·t)
Padeye attachment weld — BTH-1 §3-3.4	44.87 MPa	80.50 MPa	0.557	Pass
Governs at the top-2 pin (x = 6000 mm): direct 17.7 MPa + weld-group bending 27.1 MPa from the beam-local in-plane pin force × pin height (conservative linear combination on the throat). Weld group modelled as two parallel fillet lines under the plate — the in-plane moment from the pin's horizontal component is the §3-3.1 eccentricity provision applied to the weld.
Equations used $F_{v} = \frac{0.60 E _{xx}}{1.20 N _{d}}$ (BTH-1 eq. (3-55), fillet weld throat)
Load-cycle basis — EN 13155 §5.1.2.1 / §5.1.2.2	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Elastic condition — EN 13155 §5.1.2.1 at 2 × load	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Yielded condition — EN 13155 §5.1.2.1 at 3 × load	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Design-tilt load case — EN 13155 §5.1.2.3 / §5.2.6.3.1	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Verification route and static tests — EN 13155 Table 9 / Annexes A, E	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Cross-section class — EN 1993-1-1 §5.5, Table 5.2	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Flexural buckling — EN 1993-1-1 §6.3.1	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Bending and lateral-torsional buckling — EN 1993-1-1 §6.3.2	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Shear — EN 1993-1-1 §6.2.6	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Elastic yield criterion — EN 1993-1-1 §6.2.1(5)	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Combined axial + bending — EN 1993-1-1 §6.2.9 / §6.3.3	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Padeye pin connection — EN 1993-1-8 §3.13	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Padeye attachment weld — EN 1993-1-8 §4.5.3	—	—	—	Info
EN hybrid route not selected — this check runs on the EN hybrid route.
Declared load factor — CSA hybrid basis	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Section class — S16-09 Cl.11, Tables 1 and 2	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Axial tension — S16-09 Cl.13.2	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Axial compression — S16-09 Cl.13.3	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Bending — S16-09 Cl.13.5 / 13.6	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Shear — S16-09 Cl.13.4	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Combined axial + bending — S16-09 Cl.13.8 / 13.9	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Padeye pin connection — S16-09 Cl.13.2(b) / 13.11 / 13.10 / 13.4.4	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
Padeye attachment weld — S16-09 Cl.13.13.2.2	—	—	—	Info
CSA route not selected — this check runs on the CSA hybrid route.
DNV dynamic amplification factor (Table 16-1)	—	—	—	Info
DNV overlay off (the default — decision D-6). No DNV factor is applied to any demand.
DNV skew load factor SKL (§16.2.6)	—	—	—	Info
DNV overlay off (the default — decision D-6). No DNV factor is applied to any demand.
DNV consequence factor γ_c (Table 16-5)	—	—	—	Info
DNV overlay off (the default — decision D-6). No DNV factor is applied to any demand.

Lift arrangement solution

Beam tilt 0.00°; hook over x = 3000 mm; hook load 103.4 kN (rated load + rigging + 4.8 kN beam self-weight). Required top sling lengths for the level attitude: 5874 mm / 5874 mm.

Factor ledger
Factor	Value	Acts on
Rated load (WLL, below the beam)	98.10 kN	demand
Below-the-beam rigging weight	0.50 kN	demand
Beam self-weight (lifter component, additive per §3-1.2)	4.80 kN	demand
Hook load	103.40 kN	info
Design factor Nd (Category B)	3.00	resistance
Connection / fracture design factor	1.20·Nd = 3.60	resistance
Additional impact factor	none — §3-5.1: the design factors already embed peak impact of 50 % (Cat A) / 100 % (Cat B) of the lifted load	demand

Rigging solution
Sling	Tension (kN)	Angle from vertical	H (kN)	V (kN)
top-1	60.1	30.7°	30.7	51.7
top-2	60.1	30.7°	-30.7	51.7
bottom-1	49.3	0.0°	0.0	-49.3
bottom-2	49.3	0.0°	0.0	-49.3

Critical sections
Station	x (mm)	N (kN)	V (kN)	M (kN·m)
top lug 1	0	-30.7	2.4	4.61
top lug 2	6000	-30.7	-2.4	4.61
midspan	3000	-30.7	0.0	8.20
max \|M\| (x = 3000 mm)	3000	-30.7	0.0	8.20

Beam axial

compression 30.7 kN

Deflection (serviceability)

2.1 mm vs user limit 30.0 mm

Rated-capacity envelope

WLL at utilisation 1.00 versus span, from the same check engine as every number above. Spans 2400–12000 mm in 8 steps; the arrangement shape scales with the span (sling angle preserved); everything outside this grid is uncomputed, not passing.

WLL vs span (arrangement shape held)

WLL at U = 1.00
this design

Governing checks along the curve: Padeye attachment weld — BTH-1 §3-3.4.

Sling and shackle schedule

The load each piece of rigging gear must be rated to carry at this geometry. Required ratings only — slings, shackles and hooks are rated proprietary gear and are not designed here.

Sling	Tension	Angle from horizontal	Angle from vertical	Required rating
top-1	6.13 t	59.3°	30.7°	≥ 6.13 t at this angle — apply the manufacturer's angle/configuration factors; shackle WLL likewise.
top-2	6.13 t	59.3°	30.7°	≥ 6.13 t at this angle — apply the manufacturer's angle/configuration factors; shackle WLL likewise.
bottom-1	5.03 t	90.0°	0.0°	≥ 5.03 t at this angle — apply the manufacturer's angle/configuration factors; shackle WLL likewise.
bottom-2	5.03 t	90.0°	0.0°	≥ 5.03 t at this angle — apply the manufacturer's angle/configuration factors; shackle WLL likewise.

Marking and proof-load block

The information the nameplate and test certificate need (ASME B30.20-2021 §20-1.2.1 and §20-1.3.9.2) — reported as obligations, not computed checks.

Rated load (WLL)

10.00 t

Span

6000 mm

Lifter self-weight

0.49 t

Permitted sling angle

45°–90° to the horizontal

Permitted tilt

± 6°

ASME BTH-1 Design Category

ASME BTH-1 Service Class

Load test (ASME B30.20 §20-1.3.9.2)

Recommended before first use at 125 % +5/−0 % of rated load (12.50 t); OSHA 29 CFR 1926.251 mandates proof testing separately for US construction use.

Also required on the marking

Manufacturer name and contact, serial number, and product-safety labels per ANSI Z535.4 (B30.20 §20-1.2.1).

Awaiting source / out of scope

Check	Demand	Capacity	U	Status
Fatigue — EN route	—	—	—	Out of scope
Not computed, by design: ≤ 16 000 cycles EN 13155 §5.1.2.1 itself waives the fatigue proof; above that the route gates on the EN 13001 chain (§5.1.2.2) — EN 1993-1-9 S-N mathematics must not pretend to substitute for it.
Fatigue — CSA route	—	—	—	Out of scope
Not computed, by design: S16-09 Cl.26 is live-load-induced fatigue under specified loads with NBCC cycle bases; a lifting device's spectrum is the qualified person's. The ASME route offers a computed fatigue check.
Local web yielding / crippling at load introduction	—	—	—	Awaiting source
BTH-1 has no explicit web local yielding/crippling provision — the honest options are a user-supplied capacity or a declared AISC 360 cross-reference; neither is wired yet.
Minor-axis bending — BTH-1 §3-2.3.4	—	—	—	Out of scope
The vertical-plane solve produces no minor-axis bending; the check activates with the future transverse CoG-offset feature (eq 3-25).

Assumptions

The beam and the lifted load are treated as rigid bodies for the attitude solve — beam deflection does not feed back into the tilt. Valid while deflections are small relative to the geometry; the small-deflection validity screen warns when they are not.
Slings are straight, inextensible, and weightless in the geometry solve (no catenary, no elongation compatibility). Below-the-beam rigging weight is lumped at the load's centre of gravity.
With more than two bottom attachment points the load distribution is statically indeterminate: the declared per-point shares are the engineer's own, and the bottom slings are treated as vertical.
The hook is a frictionless point at which the top slings meet; shackle pins are frictionless and transmit no moment.
The solve is in the vertical plane containing the beam axis. A transverse (out-of-plane) centre-of-gravity offset is outside the current solve and must be assessed separately.
Beam self-weight is applied as a uniform line load over the span (prismatic member), resolved into axial and perpendicular components under the solved tilt.
The deflection diagnostic integrates bending curvature only (no shear deformation), relative to the chord between the beam ends, and is serviceability information — never a code pass/fail (BTH-1 §3-5.3 places deflection limits with the qualified person).
The axial-buckling length is the full span with K = 1.0 about both axes unless overridden — shackle pins restrain neither end rotationally, and using the full span is exact for end lugs and conservative for inboard ones.
For the §3-2.5 critical-stress check, the peak normal stress and peak shear stress at a section are conservatively combined at the same point, although they occur at different fibres.
Fatigue stress ranges assume full 0 → rated-load cycles. A measured or spectrum loading basis belongs to the §3-4.6 cumulative method, which this pack does not compute.
One padeye specification (plate, hole, pin, edge distance, weld) is applied at every lug; each pin is evaluated with its own solved force and the governing pin is named.
The padeye weld group is modelled as two parallel fillet lines under the plate; the pin force's direct shear and the in-plane moment from its horizontal component at the pin height are combined linearly on the throat — a conservative weld-line treatment.
EN HYBRID route: design loads use the EN 13155:2020 §5.1.2.1 coefficients (2 × elastic / 3 × yielded, incl. the 6° design-tilt case) but resistances come from EN 1993-1-1/-1-8 with the recommended partial factors (γ_M0 = γ_M1 = 1.00, γ_M2 = 1.25; National Annexes may differ) — NOT from EN 13001-1/-3-1, which EN 13155 Annex A.1 nominates and which are not part of this assessment. Full EN 13155 compliance is not claimed. Annex A.1's own NOTE routes buckling and stability guidance to the EN 1993-1 series.
The EN design-tilt case re-closes the statics with the beam held at the design tilt (both signs) and envelopes the demands — a strength load case per EN 13155 §5.1.2.3/Annex A.1, not a claim that the free hang equilibrates at that angle.
EN route classification: elements are classified against the pure-compression Table 5.2 limits whenever the member carries net axial compression anywhere, else the pure-bending limits — conservative with respect to the exact combined bending-plus-compression columns, which need the plastic stress-block position α.
EN route LTB: EN 1993-1-1 defines but does not give M_cr. It is computed from the classical doubly-symmetric fork-support elastic critical moment with C₁ = 1.00 (uniform moment — conservative); closed sections take I_w = 0. Equivalent-uniform-moment factors C_my = C_mLT = 1.00 in the Annex B interaction for the same reason.
CSA HYBRID route: factored resistances per CSA S16-09 (the held edition — S16-14 and S16:24 are later editions) against demands multiplied by the USER-DECLARED load factor α_f. S16-09 Cl.7.2 takes load factors from NBCC Art. 4.1.3.2 and Canada has no below-the-hook device standard, so the load side is the project's engineering decision — the route gates until α_f is declared, and no S16 compliance is claimed for the load side. ω₂ = 1.00 conservative; ω₁ = 1.0 per Cl.13.8.5(b).

Source traceability

MECH_STATICSRigid-body statics
Equilibrium of the suspended beam + load + inextensible-sling system: a stable attitude is a constrained minimum of potential energy; sling tensions follow from force balance on each rigid body. Public-domain mechanics identities; no code coefficients.
DOC_DNV_ST_N001DNV-ST-N001 · 2018-09, amended 2020-01 · §16.3.4.2 (sling angle ≥ 45° to horizontal); §16.2.2.2 (CoG-above-lift-points stability warning); §16.9.3.1 GN3 (in-rigging spreader lateral-load exemption with padeye offset check obligation)
Operational guidance references for the diagnostics. The computed overlay factors cite the dedicated Table 16-1 / §16.2.6 / Table 16-5 entries below.
MECH_BEAMEuler–Bernoulli beam identities
Piecewise-analytic N/V/M diagrams from point pin forces (with the H·e transfer couple at eccentric pins), uniform self-weight resolved under tilt, and double integration of M/EI for the chord-relative bending deflection. Public-domain mechanics identities.
MECH_SUSPENSION_STABILITYSuspended-assembly roll stability
Pendulum/metacentric argument for a body hung from flexible slings: the hang is roll-stable when the effective suspension axis sits above the centre of gravity. Reported as a DIAGNOSTIC, not a code check (decision D-10). DNV-ST-N001 §16.2.2.2 flags the same hazard.
ASME_BTH1_DESIGNASME BTH-1 · 2020 · §2-2 (Design Category), Table 2-3-1 (Service Class), §3-1.2 (loads incl. lifter component weights), §3-1.3.1 (N_d = 2.00/3.00/6.00), §3-1.3.2 (1.20·N_d fracture/connection), §3-1.4 (SC0 fatigue exemption), §3-1.7 (design wall thickness 0.93×nominal ERW / nominal SAW / smaller when unknown), §3-5.1 (impact embedded in design factors), §3-5.3 (deflection limits are the qualified person's)
Design-basis clauses verified against the licensed PDF 2026-08-05. Category and Service Class selection remain the qualified person's.
ASME_BTH1_MEMBERASME BTH-1 · 2020 · §3-2.1 eqs (3-1)/(3-2); §3-2.2 eqs (3-3)/(3-4)/(3-5); §3-2.3.1 eqs (3-6)/(3-7)/(3-8) incl. the any-length rule for compact tubes/boxes; §3-2.3.2 eqs (3-9)–(3-17) with the C_LTB not-braced branch; §3-2.3.4 eq (3-25); §3-2.3.5 eqs (3-26)/(3-27); §3-2.3.6 eq (3-28) with its h/t validity limit; §3-2.4 eqs (3-29)–(3-36) with F_e′ and C_m = 1.0; §3-2.5 eq (3-37); §3-2.6 + Table 3-2.2-1 width–thickness limits
Chapter 3 member provisions for I, box, and circular-hollow sections, verified equation-by-equation against the licensed PDF 2026-08-05.
BENCH_SDC_BTH1SDC Verifier BTH-1 spreader benchmark · published (BTH-1-2023 basis)
Independent published benchmark adopted as validation case SB-VC-BTH1-01. BTH-1-2020's Summary of Changes does not touch §3-2.3, so eqs (3-6)/(3-7) match the 2023 basis used by the benchmark.
ASME_BTH1_CONNECTIONASME BTH-1 · 2020 · §3-3.1 (eccentricity provision; eq (3-38) bearing); §3-3.3.1 eqs (3-45)–(3-52) pin-connected plates; §3-3.3.2 (combine pinhole and member stresses); §3-3.3.3 (pinhole fatigue at Stress Category E on the net area); §3-3.3.4 eqs (3-53)/(3-54) pin bearing on the projected area; §3-3.4 eq (3-55) weld shear
Connection provisions for the padeye/pinned end checks. Verified against the licensed PDF 2026-08-05; the pin-plate equations also match the platform's benchmark-validated lifting-lug implementation.
ASME_BTH1_FATIGUEASME BTH-1 · 2020 · §3-4, Tables 3-4.3-1 / 3-4.4-1, eqs (3-56)/(3-57)
Fatigue provisions; Service Class 0 exempt per §3-1.4.
EN_13155_CONDITIONSBS EN 13155 · 2020 · §5.1.2.1 (≤ 16 000 load cycles: elastic condition 2 × the sustained load without permanent deformation; yielded condition 3 × without releasing the load; coefficients cover load uncertainty and the hoisting impact factor, and fatigue proof is not necessary); §5.1.2.2 (> 16 000 cycles: proof per EN 13001-1/-2/-3-1 with γ_n = 1.4 — not part of this assessment); Annex A.1 (calculation verification: both conditions, allowable-stress / limit-state methods, max tilting angle in the calculation, buckling guidance routed to the EN 1993-1 series)
The EN HYBRID route's load basis, verified against the licensed PDF 2026-08-05. Resistances come from EN 1993 (see the member/connection sources) — full EN 13155 compliance is not claimed.
EC3_MEMBEREN 1993-1-1 · 2005 (+AC:2006/2009) · §3.2.5(3)/§3.2.6 (nominal dimensions; E, G = E/2.6); §5.5.2 + Table 5.2 (classification); §6.1 (γ_M0 = γ_M1 = 1.00, γ_M2 = 1.25 recommended); §6.2.1(5) eq (6.1); §6.2.3–§6.2.10 (eqs 6.5–6.45 cross-section resistances incl. shear areas and the M–N/M–V reductions); §6.3.1 (eqs 6.46–6.51, Tables 6.1/6.2); §6.3.2 (eqs 6.54–6.56, Tables 6.3/6.4, §6.3.2.1(2) and §6.3.2.2(4) exemptions); §6.3.3 eqs (6.61)/(6.62) with Annex B Method 2 (Tables B.1/B.2)
Member resistances for the EN HYBRID route, transcribed clause-by-clause from the licensed PDF 2026-08-05 into the shared platform implementation. M_cr is not given by the standard — see the elastic-stability mechanics source.
EN_13155_TILTBS EN 13155 · 2020 · §5.1.2.3 (attachments intended to tilt: design for ≥ max working angle + 6°; not intended: ≥ 6°); §5.2.6.3.1 (a lifting beam intended for horizontal use shall tolerate a tilt of up to 6° from the horizontal); Annex A.1 (the maximum permissible tilting angle shall be taken into account in calculations)
The mandatory design-tilt load case. Verified against the licensed PDF 2026-08-05.
EN_13155_VERIFICATIONBS EN 13155 · 2020 · Table 9 (lifting beams: mechanical strength verified by A.1 calculation OR E.2 type test / E.1 individual test); Annex A.2 (generic type test F₃ = 3 × WLL ± 2 %, ≥ 1 min, no shock, several positions); Annex A.3 (individual test F₂ = 2 × WLL, no permanent deformation); Annex E.1/E.2 (lifting-beam-specific tests; E.2 at 1.5 × F_S); §7.2.1 (minimum marking)
Verification-route and marking obligations reported to the user. F_S in Annex E.2 is not defined in the standard's §3 terms — the report presents the test options without inventing a resolution. Verified against the licensed PDF 2026-08-05.
MECH_MCRElastic lateral-torsional stability
Elastic critical moment of a doubly symmetric beam between fork supports: $M_{cr} = C_{1} \frac{π ^{2} E I _{z}}{L ^{2}} \frac{I _{w}}{I _{z}} + \frac{L ^{2} G I _{t}}{π ^{2} E I _{z}}$ — the classical elastic-stability solution (Timoshenko), public-domain mechanics. EN 1993-1-1 §6.3.2.2(2) defines M_cr but gives no formula. C₁ = 1.00 (uniform moment) is the conservative default; closed sections take I_w = 0.
EC3_PINEN 1993-1-8 · 2005 (+AC) · §3.13, Table 3.9 (Type A geometric requirements, a and c from the hole edge), Table 3.10 (bearing F_b,Rd = 1.5·t·d·f_y/γ_M0, f_y the lower of pin and part; pin shear/bending/combined criteria), Figure 3.11 (pin bending model)
Pin-connection provisions, verified against the licensed PDF 2026-08-05; identical formulas to the platform's lifting-lug EC3 route. Pin shear/bending need the shackle fork geometry and are reported as the engineer's obligation on the pin row.
EC3_WELDEN 1993-1-8 · 2005 (+AC) · §4.5.3.3 simplified method, eqs (4.2)–(4.4) with Table 4.1 β_w (0.8 / 0.85 / 0.9 / 1.0 by parent grade); §4.5.1(2) minimum effective length; §4.5.2(2) minimum throat 3 mm
Fillet-weld design resistance for the padeye attachment weld, verified against the licensed PDF 2026-08-05. The simplified method is direction-independent and conservative relative to the directional method.
CSA_S16_DESIGNCSA S16 · S16-09 (held edition; S16-14 and S16:24 are later editions) · Cl.2.2 (E = 200 000 MPa, G = 77 000 MPa assumed; C_e = π²EI/L²); Cl.6.1.1/Cl.7.2 (limit states: φR ≥ Σα_i·S_i with load factors from NBCC Division B Art. 4.1.3.2 — the NBCC is not part of this assessment, so the load factor is a declared project value); Cl.6.3.3.1 (provision for impact-inducing live loads); Cl.10.3/10.4 (effective length; KL/r ≤ 200)
Design-basis clauses of the CSA HYBRID route, verified against the licensed PDF 2026-08-05. Canada has no below-the-hook device standard: the demand-side load factor is the user's declared project value (undeclared gates the route), and no S16 compliance is claimed for the load side.
CSA_S16_MEMBERCSA S16 · S16-09 · Cl.11 + Tables 1/2 (classification incl. the web limits' coincident-axial term and the 11.3.2(b) HSS flat convention b = nominal − 4t); Cl.13.2 (tension); Cl.13.3.1/.2 (C_r unified curve, n = 1.34/2.24; F_e incl. torsional F_ez); Cl.13.4.1.1/.3 (shear, unstiffened branches; tubes); Cl.13.5 (M_r = φZF_y / φSF_y); Cl.13.6 (LTB: M_u, the 1.15·φ·M_p·(1−0.28·M_p/M_u) cap, 13.6(c) closed-section exemption, C_w = 0 for RHS); Cl.13.8.2/.3/.4/.5 (interaction, three cases, U₁, ω₁); Cl.13.9 (tension + bending)
Member resistances transcribed clause-by-clause from the licensed PDF 2026-08-05 into the shared platform implementation. ω₂ = 1.00 conservative default; ω₁ = 1.0 per Cl.13.8.5(b) for a series of point loads between supports.
CSA_S16_CONNECTIONCSA S16 · S16-09 · Cl.13.2(b) (pin connections T_r = 0.75·φ·A_n·F_y); Cl.13.11 (block shear; the clause's note endorses the second term for plate tear-out along parallel planes toward the edge); Cl.13.10(a) (bearing B_r = 1.5·φ·F_y·A on the contact area); Cl.13.4.4 (pins V_r = 0.66·φ·A·F_y); Cl.13.13.2.2 + Table 4 (fillet welds, φ_w = 0.67; base-metal fusion face); Cl.12.4 (fitted-pin proportion rules — reported as information, see the pin row)
Padeye/pin/weld provisions, verified against the licensed PDF 2026-08-05. The fillet-weld directional bonus (1 + 0.5·sin^1.5 θ) is deliberately not claimed (θ = 0, Mw = 1.0 — conservative).
DNV_N001_TABLE_16_1DNV-ST-N001 §16.2.5 · 2018-09, amended 2020-01 · §16.2.5, Table 16-1 (DAF in air, minimum values, single hook)
Dynamic amplification factor by environment column and static hook load. For $3 < SHL \leq 100$ t: onshore $1.10$ , inshore $1.07 + 0.05 100/ SHL$ , offshore $1 + 0.25 100/ SHL$ ; banded constants above 100 t. Items lighter than 3 t are taken as 3 t (note 1). SHL here = rated load + rigging + beam self-weight from the solved model. Shared platform implementation, cross-checked against the lifting-lug calculator's independently verified values.
DNV_N001_SKLDNV-ST-N001 §16.2.6 · 2018-09, amended 2020-01 · §16.2.6.9 (SKL = 1.00, statically determinate lift incl. a single spreader bar, sling length tolerance within ±0.5 %); §16.2.6.2/3 (simplified values valid only for sling angles 45°–80° to the horizontal; otherwise case-by-case)
Skew load factor. This pack derives SKL = 1.00 only for a statically determinate arrangement inside the angle-validity band; anything else requires the project rigging analysis value to be entered.
DNV_N001_TABLE_16_5DNV-ST-N001 §16.8.3 · 2018-09, amended 2020-01 · Table 16-5 row 1 (γ_c = 1.30 — the row's scope covers lifting equipment that is not load-tested, naming spreader frames and beams among its examples); §16.8.5.1 (spreader bars/frames and lifting beams treated the same way as lift points)
Consequence factor for the spreader itself: 1.30 per Table 16-5 row 1 scope. A load-TESTED spreader falls out of row 1 but stays at 1.30 as a lift-point attachment per §16.8.5.1 — the factor is deliberately not a user knob.

This is a preliminary design and verification tool, not a replacement for a lift plan, a proof test, independent engineering review, or a competent person's approval. Slings, shackles and hooks are rated proprietary gear and are not designed here.