X-Ray Crawler is similar to conventional radiography however an x-ray source tube on a crawler device is run inside the pipe to each weld. Film is wrapped around the welds and the source tube is excited. The technique is quick and can inspect on average 100 welds per day. The advantages of X-ray crawlers are their speed and the short exposure time. The film is also crisper and much less grainy when compared to conventional radiography using Iridium type sources.