Abstract: A measuring tube for a flowmeter. The measuring tube is lined with a tubular lining of thermoplastic material, particularly PTFE or PFA, which comes into contact with the measured substance which flows through the tube. The ends of the tubular lining are flanged around end flanges of the measuring tube after the ends of the tubular lining have been plasticised by heating. The plasticised ends of the tubular lining are turned outward by more than 90.degree. and then forced into undercuts in the end faces of the end flanges. Upon cooling, the ends of the lining are in intimate contact with the end faces of the end flanges and the undercuts in the end faces.

Abstract: An armored rotameter capable of accurately measuring low flow rates, the meter including a metal body provided with a bore defining a vertical flow tube having a lower inlet into which a fluid to be metered is admitted and an upper outlet from which the fluid is discharged. Disposed in the flow tube is a float having a guided stem which includes a lateral pin projecting through a slot in the front wall of the meter body, the pin riding up and down the slot as the float moves up and down the tube as a function of flow rate. The pin is coupled to one end of a bar magnet link that is external to the meter body and is swingable about a center pivot, the link being caused to swing to an extent and direction in accordance with float movement. The slot and link are sealed by a pressure plate secured to the front face of the meter body.