| 摘要 |
A method of cleaning tubing in an operating heater, in which the tubing has an inlet and an outlet. While the heater is in operation, a hollow, metallic and/or tubular mesh pig is run through the tubing from the inlet to the outlet. Cleaning should be done before contaminant has hardened. An improved pipe pig, preferably hollow, metallic and/or made from tubular mesh, has scraping edges made from longitudinal edges of a wire. The tubular mesh may be a knit, weave or may be knotted. The pig is preferably radially expandable up to twice its fully compressed radius, and may have an expander to force it radially outward. The pipe pig is preferably made of a resilient wire having a polygonal cross-section. |
