The compressor bearing abnormal wear analysis and processing

Analysis and deal with 2020 - compressor bearing abnormal wear 12 - 01 moor-jankowski Lv Bing 1 2 ( 1. CPC JiChai group, chengdu compressor factory, 2. The Great Wall drilling engineering co. , LTD. Gas projects department) in a 1 provides an overview of a number of 200851 # ZTY470 compressor unit, is mainly composed of dynamic compression, instrumentation, air cooler assembly and parts. Unit for the level of compression, equipped with three import power cylinder, two compression cylinders are 7 ', the air gap opening, two-cylinder double-acting, unit is mainly used for gas pressurization processing. Unit design parameters are as follows: model: ZTY470MH7x7 medium: sour gas emissions: 17 x104nm3 / d inlet temperature: 0 to 35 ℃ inlet pressure: 1. 8 MPa exhaust pressure: 5. 5 MPa2 problems arising from the operation on April 23, 2012, the unit suddenly appeared in the process of running without oil flow alarm, then the unit automatically stop immediately. Stop after disassembly check, found that the 3 pair of spindle watts, 1 pair of thrust tile wear in different situation, take a typical thrust tile samples ( Figure 1 shows the thrust tile surface alloy in large area of spalling, figure 2 so far on tile surface have no obvious wear) 。 The booster station ZTY470 compressor thrust tile, spindle watts has been normal use, as of downtime, run 9065 unit. 8h。 3 the cause of the problem analysis of 3. 1 site condition according to the site conditions, the use of A - integrated natural gas compressor JAX software line condition, unit load rate is about 80% ( Figure 3) , therefore, eliminate overload use. 3. Cause analysis, the failure parts (2 ZSnSbllCu6） The chemical composition analysis, the chemical composition of bearing materials meet the GB/T1174 - basically 92 ZSnSbllCu6 chemical composition of the standard requirements; Size detection alloy thickness of 0. 3 - 0. 6 mm, comply with the design requirements; Testing abrasion hardness HB31 - bearing materials 32, meet HB&ge product design; The requirements of 27. The thrust tile alloy strip parts failure characteristics: bearing alloy surface tear, rolling local irregular lump, flake dot, remains of parts of the peeling and irregular and matrix alloy layer, the surface has significant residual conchoidal fracture morphology ( Figure 4) 。 To sum up, the thrust tile phenomenon of alloy spalling failure judgement to fatigue spalling. Damage mechanism analysis: extend from sliding surface crack in the area of high load, high rendering and may render the mesh extended to alloy layer is rolling or erosion phenomenon, the reticular crack in combination with change of direction on the surface, lead to bearing alloy lining pieces on peeling, flaking edge is clear. Due to the machine itself bearing hole and shaft neck deformation factors, such as uneven distribution of load bearing working surface produce local peak pressure; Excessive oil pulse pressure fluctuations, accompanied by high pressure gradient, lead to more than the bearing fatigue limit, cause metal fatigue spalling; Poor quality lubricating oil ( Booster station of lubricating oil is the product of a certain refinery of the oil analysis, according to a report in the lubricating oil containing water) Lubrication part, lubrication performance, local temperature rise will increase, sharply reduce the friction properties of the alloy, greatly accelerate the tiles failure, shorten the service life of the tiles, and other several compressor has a similar phenomenon occurs. As a result, can be concluded that the booster station compressor load is normal, lubricating oil quality is not stable, causing tiles lubrication performance, temperature rise, is the main cause of tiles to accelerate the failure. 4 fault handling ( 1) Replace worn bearing; （ 2) Crankcase oil change; （ 3) Requirements in a timely manner to replace oil and regularly make oil analysis. 5 conclusion after the replacement of bearing and lubrication oil, the unit running well so far. In order to reduce the fault occurs, it is recommended that the user strictly monitoring the change of the unit operation parameters, check the oil regularly, tracking product quality, at the same time to add perfect maintenance content, to ensure the long-term and stable operation of unit. Source: the compressor technology