Mapping Erosion in Gun Bores

The problem:

Today, more than ever, both end-users and manufacturers of high-performance gun tubes need reliable and quantitative measurement and inspection tools.  Unfortunately, most of the commonly used bore mapping tools in use today were developed in the 1940's.  Air gages and "star" gauges have been in common use for verifying dimensions of gun barrels for over 50 years.  Although these gauging tools can work well for certain types of simple and repetitive gauging applications, both methods are inherently limited in their range and flexibility — and neither method can generate a full three-dimensional map of a gun bore or chamber.

The solution:

LTC's laser bore mapping systems provide a superior alternative to conventional bore gauges.  Our laser profiling sensors, based on our Laser MicroMap™ system and supported by our LaserViewer™ software, have significantly larger measurement ranges than air gages and star gauges, can rapidly scan the gun tube surface in a non-contact manner, and generate a three-dimensional image that is quantitative and highly accurate.  These laser sensors project a tiny laser beam (approximately 0.002 inches in diameter) onto the part surface and can acquire thousands of measurements per scan.  Diameter and erosion data can be evaluated using our LaserViewer™ analysis software, or it can be automatically post-processed and displayed in a tabular summary report.  Results can be exported to Excel™, MATLAB™, or other programs for further analysis and display.                                                                  

Bore mapping data is provided in several operator-friendly formats, including:   

Cross-sectional display of the bore at any elevation

Tabular summary report

Contour view display of the full bore length

Zoom function for flaw magnification

Key advantages of laser mapping include:

Non-contact measurement

Automated data acquisition

Full-featured analysis and reporting functions

Quick changeover to new barrels

Complete surface characterization

Full length bore mapping

Photograph-quality bore and chamber image using LaserVideo™ imaging

Related applications:

Corrosion and pitting measurement

Crack detection in nuclear steam generator tubes

(click picture to enlarge)

LaserVideo™ image (left) reveals small chips on edges of lands, confirmed by dimensional image (right)