Precise measurement of upper and lower axial profiles
PGI NOVUS Dual Bias Gauge
The ball screw is aligned using its shaft or its thread and measured. The precise relationship between the upper and lower thread profiles is established following automated alignment, measurement and helix angle corrections.
Axial analysis
Full surface and dimensional assessment, including pitch circle diameter (PCD)
User defined analysis templates are automatically applied and ‘Pass / Fail’ criteria and tolerances can be set to design requirements.
Analysis solutions
• Helix angle correction
• Contact points
• Axial surface finish
• Radius
• Form
• Gothic arch
• Pitch
• PCD and tolerances
Precise auto-alignment ensures true axial thread profiles
1. Alignment on shafts - Crest positions on the shaft are used to determine the angular rotation required for perfect alignment using the Form Talysurf® PGI NOVUS rotary stage. This ensures that the true thread profile is measured.
2. Alignment on threads section - Crest positions on the thread are used to find the angular rotation required.
Helix angle correction and thread analysis
Helix angle correction uses the axial measurement taken along the gothic thread profile, transforming it so that it represents a measurement taken perpendicular to the thread.
This allows for tolerancing and analysis of the profile against the design drawing and software simulation of the ball bearing fit within the gothic thread.
Critical gothic arc features such as contact angle, arc radii and distance between centres can be determined as shown in the diagram below.