Pre-heating oven. Oil heating for bronzing plate, constant temperature auto control, oilpumpcirculation.
烫金版油加热，恒温自动控制，油泵循环。
2
At the initial stage of development, the main oil production methods give priority to hydraulic piston pump and closed hot water circulation.
开发初期，主导开采方式主要以“水力活塞泵、闭式热水循环”等采油工艺为主。
3
A smoke extractor with an oil-stain cleaning device consists of a shell, a motor, an impeller, a cleaning circulationpump, an oil sump, a liquor-collecting container and an air inlet cap.