GB1426441A - Tube grinding and polishing machines - Google Patents

Abstract

1426441 Grinding tubes DELANEY GALLAY Ltd 4 May 1973 [5 May 1972] 21175/72 Heading B3D An apparatus for grinding or polishing the internal surfaces of welded tubes, such as used in brewery, process and chemical industries, comprises a main drive shaft 1 for driving at least one gear train 5, 6 carried by a cage 4, the output shaft 8 of the or each gear train carrying a grinding/polishing head 7, the arrangement being such that on rotation of the drive shaft the cage and the or each head are rotated around the axis of the drive shaft as and until the head engages a tube wall whereupon the head is counter-rotated about its axis. As described, the apparatus has two grinding/polishing heads 7 on shafts 8 connected by flexible joints 10 to the shafts of gears 6 which are rotatably mounted in the cage 4 and connected by intermediate gears 5 to a gear 2 attached to a coupling member 1 of the drive shaft. A shield 9 is secured to the cage and has slots permitting radial movement under centrifugal action of the shafts 8 which may be flexible. When the coupling is rotated, the cage 4 and heads 7 rotate about the axis of the coupling until the heads engage the tube wall and the resistance causes an epicyclic effect and the heads to counter-rotate about their axes, the mass of the cage assembly, being greater than that of the grinding head shaft assemblies, causing, the unit to rotate freely about the axis of the coupling while the grinding heads counter-rotate.