Remanufacturing process

Every compressor that leaves the factory has gone through a specific procedure. It receives a unique number that is stamped on the casting. This number remains throughout its lifetime and is referenced in any related communication.

The remanufacturing process starts with oil draining, after which the compressor is completely disassembled. All components are inspected and measured, thus establishing their size and deviations, using micrometers. In certain circumstances it may be possible to rebuild the crankshaft and have the cylinder bores re-drilled in the casting. Components within the manufacturer-specified limits are remanufactured. All other components are replaced, unless there are contractual provisions requiring the replacement of certain parts. Slat valves and piston rings are discarded regardless of their condition. All disc valves have a flat surface. The stator windings are removed, identified with the compressor and sent to an electrical rewinding department where they are tested or rewound. Before unwinding each coil, the coils are lifted and measured using a micrometer and the number of turns is counted. The stator windings are unwound, the stator and the rotor are then cleaned. The coil size and helix information is entered into a special winding machine, which winds them up and prepares them for installation. The stator windings are then manually wound with the placement of class "F" insulation and impregnated with freon-resistant varnish. Each coil is tested to determine the 2000V-ground lightning flashover temperature by taking and recording ohms readings with several multimeters, then the coil is tested at full load in a transformer. All cast components i.e. body, heads, end caps are thoroughly cleaned using a Vaqua water jet containing abrasive powder or degreaser.

The compressor is assembled by an experienced worker, with checks carried out at each stage. Once assembled it is subjected to an electrical bench test with a flash point tester and the ohm readings are once again recorded. The compressor is then transferred to a testing center where it is subjected to the most rigorous testing procedure in our unique, customized stand, placed open and under load. At this stage, the operation of the compressor is recorded in an overhaul and test certificate:

• amperage readings are reported to ensure the three phases are balanced;
• oil pressure is reported while the compressor rotates clockwise and counterclockwise;
• oil return is checked through the monitoring glass;
• each unloading is checked for proper functioning;
• when the compressor reaches a minimum of 7 bar discharge pressure, it is switched off and restarted;
• a pumping test is performed to ensure that no amount leaves through the discharge valve plates.

The test oil is drained from the compressor and new oil is added up to the correct level. The compressor is then filled with 30 bar of oxygen-free dry nitrogen and submerged under water to ensure it is airtight before being dehydrated and purged up to 2 tors or lower. The compressor is filled with 2 bar of oxygen-free dry nitrogen before being powder coated in the original manufacturer color, unless otherwise specified.