• Joint must fulfill its function and withstand working load
Aim of Calculation
Determine bolt dimension allowing for: • Strength grade of the bolt • Reduction of preload by working load • Reduction of preload by embedding • Scatter of preload during tightening • Fatigue strength under an alternating load • Compressive stress on clamped parts
Beam Geometry, Ex. 2
• Axial force, FA • Transverse force, FQ • Moment of the plane of the beam, MZ
Rotation of Flanges
• Axial force, FA (pipe force) • Bending moment, MB • Internal pressure, p
Flanged Joint with Plane Bearing Face, Ex. 1
• Axial force, FA (pipe force) • Torsional moment, MT • Moment, MB
Flanged Joint with Plane Bearing Face, Ex. 2
Determining Bolt Dimensions
• Once working load conditions are known allow for:
– Loss of preload to embedding – Assembly preload reduced by proportion of
1. Range of Validity
• Steel Bolts • M4 to M39 • Room Temperature
2. Choice of Calculation Approach
• Dependent upon geometry
– Cylindrical single bolted joint – Beam connection – Circular plate – Rotation of flanges – Flanged joint with plane bearing face
axial bolt force – Necessary minimum clamp load in the joint – Preload scatter due to assembly method
Calculation Step R1
• Estimation of bolt diameter, d • Estimation of clamping length ratio, lK/d • Estimation of mean surface pressure under
Definitions
• Covers high-duty bolted joints with constant or alternating loads
• Bolted joints are separable joints between two or more components using one or more bolts
• Axial force, FA (pipe force) • Transverse force, FQ • Torsional moment, MT • Moment, MB
Flanged Joint with Plane Bearing Face, Ex. 3
• Axial force, FA (pipe force) • Transverse force, FQ • Torsional moment, MT • Moment, MB
3. Analysis of Force and Deformation
• Optimized by means of thorough and exact consideration of forces and deformations including:
– Elastic resilience of bolt and parts – Load and deformation ratio for parts in
Cylindrical Singl源自 Bolted Joint• Axial force, FA • Transverse force, FQ • Bending moment, MB
Beam Geometry, Ex. 1
• Axial force, FA • Transverse force, FQ • Moment of the plane of the beam, MZ
assembled state and operating state
4. Calculation Steps
• Begins with external working load, FB • Working load and elastic deformations may
cause:
– Axial force, FA – Transverse force, FQ – Bending Moment, MB – Torque moment, MT
Important Note
This summary of the VDI 2230 Standard is intended to provide a basic understanding of the method. Readers who wish to put the standard to use are urged to refer to the complete standard that contains all information, figures, etc.