a length of pipe的用法和样例：
- A length of pipe with a sharp bend in it.
- He fished a length of string out of his pocket.
- He fish a length of string out of his pocket.
- A length of pipe isolated at both ends by a valve may also suffer from over pressurization.
- Do not attempt to get extra leverage on a spanner or pipe wrench by slipping a length of pipe over the handle of the tool.This can strain the tool to breaking point.Use torque adjustable wrenches.