Allowable Equipment & Tank Nozzle Loads

Allowable nozzle force and moment reference tables and interactive evaluation engine according to API 610 (Pumps Table 5 & Annex F), API 661 (Air Coolers), NEMA SM 23 / API 612 (Steam Turbines), API 617 (Centrifugal Compressors), API 618 (Reciprocating Compressors), and API 650 Annex P (Atmospheric Storage Tanks).

Equipment Standard

Nozzle Load Compliance Evaluator

Interactive

Evaluate piping reaction forces and moments against governing allowable standard limits.

SATISFACTORY (PASS)Max Ratio: 36.8%

Nozzle Size (NPS)

API 610 Annex F Multiplier

Load Presets

Fx, Fy, FzPiping Reaction Forces (F)

Fx (Axial)

Fy (Vertical)

Fz (Transverse)

Mx, My, MzPiping Reaction Moments (M)

N·m

Mx (Torsional)

N·m

My (Bending Y)

N·m

Mz (Bending Z)

N·m

Resultant Force (Fr)36.8%

1,414 N/ 3,840 N

Resultant Moment (Mr)35.1%

949 N·m/ 2,700 N·m

Governing Axis & Status

Mz (Bending Moment Z)

✅ Reaction loads are within safe limits. Low risk of casing strain or shaft misalignment.

8-Axis Component BreakdownNPS 4" (SI Units)

Fx38%

800

Max: 2,130

Fy37%

1,000

Max: 2,670

Fz34%

600

Max: 1,740

Fr37%

1,414

Max: 3,840

Mx35%

700

Max: 1,995

My33%

500

Max: 1,500

Mz39%

400

Max: 1,020

Mr35%

949

Max: 2,700

API 610 Table 5 Allowable Nozzle Loads

SI (N, N·m)

Click any row to automatically load nozzle size into evaluator above.

Swipe the table sideways to see all axes

Size		Allowable Forces (N)				Allowable Moments (N·m)
NPS	DN	Fx	Fy	Fz	Fr	Mx	My	Mz	Mr
NPS 2"	DN 50	710	890	580	1,280	460	350	230	620
NPS 3"	DN 80	1,070	1,330	890	1,930	950	720	470	1,280
NPS 4"	DN 100	1,420	1,780	1,160	2,560	1,330	1,000	680	1,800
NPS 6"	DN 150	2,490	3,110	2,050	4,480	2,300	1,750	1,180	3,120
NPS 8"	DN 200	3,780	4,710	3,110	6,800	3,530	2,680	1,760	4,770
NPS 10"	DN 250	5,340	6,670	4,360	9,600	5,020	3,800	2,490	6,780
NPS 12"	DN 300	6,670	8,340	5,470	12,000	6,100	4,630	3,050	8,270
NPS 14"	DN 350	7,560	9,450	6,230	13,600	6,910	5,250	3,460	9,350
NPS 16"	DN 400	8,900	11,120	7,300	16,000	8,130	6,170	4,070	11,000
NPS 18"	DN 450	10,230	12,790	8,380	18,400	9,360	7,090	4,680	12,660
NPS 20"	DN 500	11,570	14,460	9,470	20,800	10,580	8,010	5,290	14,310
NPS 24"	DN 600	14,230	17,790	11,650	25,600	13,020	9,870	6,510	17,610

Engineering Guidance & Nozzle Load Best Practices

API 610 Coordinate System: The X-axis is parallel to the pump shaft centerline, the Y-axis is vertical (pointing upwards), and the Z-axis is horizontal and perpendicular to the shaft.
API 610 Annex F Multipliers: Table 5 limits may be multiplied by 1.5× or 2.0× provided the pump baseplate design and anchorage meet Annex F rigidity criteria to prevent shaft seal deflection.
API 650 Annex P Storage Tank Shell Nozzles: Large atmospheric storage tank shell nozzles are vulnerable to shell local buckling from radial force ($F_R$) and bending moments ($M_L, M_C$).
API 617 / 618 Compressor Nozzle Loads: High-speed centrifugal and reciprocating compressor casings require stringent nozzle reaction limits to safeguard rotor dynamic alignment and shaft seal integrity.
Load Mitigation Strategies: If reaction loads exceed allowable limits, re-route piping to enhance flexibility, install variable or constant spring hangers to relieve deadweight, or place pipe anchors and directional guides to isolate thermal expansion forces from the nozzle flange.