Find rugged industrial diaphragm pumps at Grainger to help handle a wide range of water-based and petroleum-based applications. Automatic demand pumps can meet U. S. Coast Guard (USCG) electrical standards for marine and RV use. Find petroleum-based pumps to help handle liquid transfer, dewatering circulation, warm oil changing and diesel fuel transfer. Pumps feature polypropylene housings and sealed motors for efficient operation. Get reliable industrial diaphragm pumps at Grainger!