Charlotte Pipe Tech Tools App provides simple, on-the-go technical tools for the plumbing industry. Tools featured include an expansion and contraction calculator and a temperature de-rating calculator and other various calculators. Ideal for plumbing engineers, contractors, architects and other industry professionals.Charlotte Pipe Tech Tools App provides simple, on-the-go technical tools for the plumbing industry. Tools featured include an expansion and contraction calculator and a temperature de-rating calculator. Ideal for plumbing engineers, contractors, architects and other industry professionals.