Cheonsei CHEONSEI has acquired immeasurable experience in the designing and manufacturing metering pumps(dosing pumps) and pump accessories, becoming the leader of pump designing and manufacturing solutions. Need more information about Cheonsei products? Contact Us Diphragm Metering Pumps Various LEM (Liquid End Material) available to inject all kinds of chemical liquids. Pulseless Metering Pumps For high precision injections with pulse rates of ±1%. AOD pumps Self-priming pump covers up to 8m static suction lift. Sealless Magnetic Pump Non seal type magnetic for highly corrosive chemical liquids. Drum Pump Electrical / Air operated motor.