摘要 |
An apparatus for cleaning tubing in an operating heater, in which the tubing has an inlet and an outlet. While the heater is in operation, a pig is run through the tubing from the inlet to the outlet and then returned to the inlet along return tubing, in parallel connection to the heater tubing. A combined pig launcher and receiver mounted parallel to the tubing, and controlled with three-way full port valves, is used to launch pigs into the tubing and remove them from the tubing. A boost pump is used to force pigs back from outlet to inlet. |