Large compressor bundle assembly

Abstract

Sliding pads are installed at several convenient locations of a rotary machine comprising barrel casing, typically in the areas adjacent the external gasket on the outer diaphragm bundle periphery. The sliding pads, made of self-lubricating material, cast iron or others graphite filled materials, will be bearing the whole diaphragm bundle weight preventing any direct contact between barrel casing internal surface and diaphragm bundle external surface, both during assembly operations and also after the diaphragm bundle has reached its final location inside the barrel casing. In this way, it is possible to prevent possible damages to both diaphragm bundle and casing housing surfaces during diaphragm bundle insertion/extraction phase into/from the barrel casing.

What is claimed is: 
     
         1 . A rotary machine, comprising,
 a barrel casing comprising a cylindrical internal surface; and   a diaphragm bundle comprising a cylindrical external surface,   wherein the diaphragm bundle during an assembly of the rotary machine is insertable in axial direction into the barrel casing with its external surface in mating relation with the internal surface of the barrel casing, and   wherein the diaphragm bundle comprises a sliding section attached to its external surface bearing the whole diaphragm bundle weight while preventing any direct contact between the internal surface of the barrel casing and the external surface of the diaphragm bundle both during the assembly of the rotary machine and when the diaphragm bundle is in its final operating position.   
     
     
         2 . The rotary machine of  claim 1 , wherein the sliding section comprises sliding pads made of self-lubricating material either as sole sliding system or installed in addition to a set of rollers. 
     
     
         3 . The rotary machine of  claim 2 , wherein the sliding pads are made of cast iron, graphite filled bronze, graphite filled nickel, plastic material, or composite material. 
     
     
         4 . The rotary machine of  claim 2 , wherein the sliding pads are positioned at several locations on the outer diaphragm bundle surface to avoid contact at any time between a mating surface of the barrel casing and the diaphragm bundle. 
     
     
         5 . The rotary machine of  claim 2 , wherein the sliding pads are installed interspersed along the circumference of the diaphragm bundle. 
     
     
         6 . The rotary machine of  claim 2 , wherein the sliding pads are installed into recesses on the external surface of the diaphragm bundle and fixed there by screws in such a way that they can protrude from the external surface of the bundle from 2 mm to 10 mm. 
     
     
         7 . The rotary machine of  claim 5 , wherein the sliding pads have substantially the shape of a section of a cylinder that copies the internal surface of the barrel casing, with a longitudinal dimension parallel to the diaphragm bundle circumference greater than the transverse dimension. 
     
     
         8 . The rotary machine of  claim 2 , wherein the sliding pads present a contact surface of dimensions configured to minimize contact pressure when the diaphragm bundle reaches its final destination. 
     
     
         9 . The rotary machine of  claim 1 , wherein the cylindrical internal surface of the barrel casing and the cylindrical external surface of the diaphragm bundle are stepped, presenting circumferential surfaces of different diameters. 
     
     
         10 . The rotary machine of  claim 1 , wherein the sliding pads comprise a blended contact surface configured to minimize the Hertzian contact pressure when the diaphragm bundle approaches the diametric steps inside the barrel casing. 
     
     
         11 . The rotary machine of  claim 1 , wherein the sliding pads have a longitudinal length between D/ 35  and D/ 15 , where D is the internal diameter of the barrel casing, and a thickness between D/ 120  and D/ 60 . 
     
     
         12 . The rotary machine of  claim 1  wherein the rotary machine is a centrifugal compressor. 
     
     
         13 . A system for assembling a rotary machine, the system comprising:
 a barrel casing comprising a cylindrical internal surface; and   a diaphragm bundle comprising a cylindrical external surface,   wherein the diaphragm bundle during the assembly of the rotary machine is insertable in axial direction into the barrel casing with its external surface in mating relation with the internal surface of the barrel casing, and   wherein the diaphragm bundle comprises a sliding section attached to its external surface bearing the whole diaphragm bundle weight while preventing any direct contact between the internal surface of the barrel casing and the external surface of the diaphragm bundle both during the assembly of the rotary machine and when the diaphragm bundle is in its final operating position.   
     
     
         14 . A method for assembling a rotary machine comprising a barrel casing comprising a cylindrical internal surface, and a diaphragm bundle comprising a cylindrical external surface, the method comprising:
 inserting the diaphragm bundle during assembly of the rotary machine in axial direction into the barrel casing with its external surface in mating relation with the internal surface of the barrel casing;   attaching a sliding section to the external surface of the diaphragm bundle;   inserting the diaphragm bundle during assembly of the rotary machine in axial direction into the barrel casing, wherein the sliding section bears the whole diaphragm bundle weight; and   preventing any direct contact between the internal surface of the barrel casing and the external surface of the diaphragm bundle during assembly of the rotary machine and when the diaphragm bundle reaches its final operating position.   
     
     
         15 . The rotary machine of  claim 3 , wherein the sliding pads are positioned at several locations on the outer diaphragm bundle surface to avoid contact at any time between a mating surface of the barrel casing and the diaphragm bundle. 
     
     
         16 . The rotary machine of  claim 15 , wherein the sliding pads are installed interspersed along the circumference of the diaphragm bundle. 
     
     
         17 . The rotary machine of  claim 16 , wherein the sliding pads are installed into recesses on the external surface of the diaphragm bundle and fixed there by screws in such a way that they can protrude from the external surface of the bundle from 2 mm to 10 mm. 
     
     
         18 . The rotary machine of  claim 2 , wherein the cylindrical internal surface of the barrel casing and the cylindrical external surface of the diaphragm bundle are stepped, presenting circumferential surfaces of different diameters. 
     
     
         19 . The rotary machine of  claim 2 , wherein the sliding pads comprise a blended contact surface configured to minimize the Hertzian contact pressure when the diaphragm bundle approaches diametric steps inside the barrel casing. 
     
     
         20 . The rotary machine of  claim 2 , wherein the sliding pads have a longitudinal length between D/ 35  and D/ 15 , where D is the internal diameter of the barrel casing, and a thickness between D/ 120  and D/ 60 .