Azipod bearing failure pdf

Azipod is the registered brand name for abb groups range of electric podded azimuth thrusters. Processes for the monitoring of exciter unit condition were ineffective in detecting deterioration prior to unit failure. Each characteristic is described in detail and is shown in diagram form, accompanied by a color photograph. Azipod v propulsion system, experienced a bearing failure in year 2000. Timken bearing damage analysis with lubrication reference guide. Tensile stresses can be very high in tightly fitted bearing components.

Mar 15, 20 the carnival legend is cruising home to tampa slower than usual because of a problem with one of its azipod propulsion units. Attributed by high number of potential failure modes due to numerous. An electric motor and the associated variable frequency drive can be designed to provide. Of all modern large cruise ships, icebreakers and high iceclass cargo vessels, roughly twothirds are fitted with azipod propulsion, according to abb. Failure modes for bearing pads include crushing, delamination, and slippage. Finally, refer to the checklist that closes out the series for suggestions on how to avoid a repetition of the. The bearing outer races are solid with the structure of the gondola and are therefore steady. Read the text associated with the picture, so as to get a better understanding of why the bearing failed. Azipod is the registered brand name of the abb group for their azimuth thruster. Naturally, improper assemblyselecting the wrong thrust bearing thick. The propulsion motor, bearings and seals are directly cooled by the surrounding sea. Heavy duty truck and trailer bearing failure analysis an iso ts 16949 certi. Install the new bearing using an arbor press fitted with a hollow or stepped punch face to press only on the outer housing of the bearing.

Nov 20, 20 pods strike again rccls allure of the seas pulled for repairs posted on november 20, 20 by rick spilman royal caribbeans allure of the seas the largest cruise ship in the world, is being taken out of service in february due a failure in one of its azipod propulsion pods. Abb turbocharging tips for the operator dieselduck. In this webinar, jason tranter first discusses the most common reasons why rolling element bearings fail, including lubrication problems, lubricant. Advantages, disadvantages of azipods and design consequences the advantages of azipod drives in comparison with traditional diesel propelled vessel with fixed propellers are 9. May 31, 2016 the aim of the webinar is to highlight the fact that it is not enough to simply use vibration analysis and other condition monitoring techniques to detect when a bearing may fail. Ultrasonic frequency bands around 250 khz to 350 khz start to give signals. This process is a function of time, temperature, speed, load and environment. Developed in finland jointly by the shipbuilding company masayards and abb, azipod is a marine propulsion unit consisting of a fixed pitch propeller mounted on a steerable gondola pod which also contains the electric motor driving the propeller.

Bearing failures maintenance worldmaintenance world. Excessive operating load is not, however, the only reason for bearing overload. Bearing failure video 24 lubrication failures youtube. When thrust bearing failures have been experienced these have, in the. Thrust and support bearing failures have been determined by arguable bearing choices in arrangement, type. Typical azipod propulsors with pulling propellers 10. Bearing failure chart types of bearing damage and failures research work some other type of common failures. Early failure is mostly attributable to inadequate handling or maintenance. Listen to this pdf listen to this pdf using readspeaker. The causes of a thrust bearing failure can be traced to a single problem or a combination of problems. The first thing to look for is an illustration that depicts similar damage to the failed bearing.

Typical azipod propulsors with pulling propellers 10 bearing, shaft seals propeller electrical motor bearings installation. After a deep root cause analysis a complete bearing system redesign. Hybrid bearing, innovation which combines the advantages of two different types of bearings. The failure of the unit in its original asbuilt configuration, and the. Such analyses can help maintenance departments determine the root cause of a bearing failure and pinpoint action that can be taken to prevent future failures. The interspace concept is a really revolutionary innovation patent pending. The cranks are connected to the pins at the top platen with bush bearing. Due to geometry misalignment axial mismatch between journal and bearing centre lines misalignment of bearing housing or shaft journal deflection under load corrective actions realign bearings. Overload on the bearing premature failure of the bearings may result from the bearing being either radially or axially loaded beyond its normal capacity.

Bearing failure its causes and countermeasures prepared by. Severe brinell marks can cause premature fatigue failure. Heavy duty truck and trailer bearing failure analysis. The bearing pressure as high as 73 mpa is encountered at full load. Pod problems lead to more problems cruise industry news.

Roller bearings, which operate with rolling elements such as balls or rollers in a raceway, are reliable and durable. Carnival legends azipod issue isnt unusual south florida. Originally developed in finland by wartsila dockyards, these are marine propulsion units consisting of electrically driven propellers mounted on a steerable pod. Development of azipod propulsion for high power arctic offshore.

Types of failure bearing failures main cause reference failures failure details rolling fatigue flaking. To accommodate the relative movements, bearing rollers are barrel. The damage has been done, to the thrust bearing itself and likely to the crankshaft as well. Vibration analysis bearing failure analysis by mobius. The failure of the unit in its original asbuilt configuration, and the subsequent failure of the original port exciter unit on 24 january, were both probably due to a breakdown in electrical insulation. The azipod technology was developed by abb, a publicly traded swiss company, about two decades ago and is billed as the most energy efficient propulsion system in. Roller bearing service damage and causes figure 23 lubrication failure rollers this is an example of a less advanced stage of spherical roller bearing failure due to inadequate lubrication. Pods strike again rccls allure of the seas pulled for. This concept makes seal maintenance possible inside the azipod and gives the ship operator a huge advantage minimising risk in operation. The one consists of two radial roller bearings supporting the shaft placed respectively in front of and behind the electric motor a.

Any static overload or severe impact can cause brinelling. This ship is a platform support vessel and is designed to carry out regular supply and cargo transport functions for. Nevrlube bearing pack, the bore in the hub should be cleaned and inspected for visual damage replace as necessary. Problems of handling ships equipped with azipod propulsion systems 235 3. When a thrust bearing failure is discovered, its usually too late. Precision bearings are industrial components that carry loads in a variety of applications.

The main market for azipod is large cruise and the opening new seaways in the north, said sakari sorsimo, senior vice president, head of abb business unite marine and ports finland. All in all azipod hydrodynamic improvements from the first units to azipod xo have been improved by 9 percent when compared to the elation results. Fatigue failure in diagonally opposed areas in top and bottom halves causes load concentration on one area of bearing. This handbook shows how to prevent bearing failure, how to avoid replacement and downtime costs, and how to solve bearing failure problems quickly when they do occur avoiding delayed orders and lost business.

Attempting to remove such components by cutting the cone inner race may. Overload may also occur due to abusive operating conditions. Design of the propeller shaft bearings and seals to improve the life cycle. Rolling bearings handbook and troubleshooting guide. Bearings may fail earlier than the expected rolling fatigue life. Bearing monitoring with technical devices urgency of. Pdf a diagnostic of dieselelectric propulsion for ships. This product introduction provides system data and information for preliminary project planning of an azipod podded propulsion and steering system outfit.

Elimination of shaft line, steering gear, rudder and stern thrusters. Azipod propulsion units are celebrating 25 years in service, and will soon rack up 12 million hours of operating time with a remarkable availability of 99. Causes and cures to understand about failures series of bearing and what are the prevention for same. Furthermore, our project and sales departments are available to advise on more specific questions concerning our products and regarding the installation of the system components. We will be pleased if this guide book assists the user in preventing early. The rollers have started to spall on the ends in a comparatively fine grained pattern. How to analyze gear failures article pdf available in journal of failure analysis and prevention 26. The azipod system was applied in the viking avant ship. What started on an azipod unit on the oasis of the seas may have turned into a near month of cancelled carnival vista july cruises due to more pod issues. A diagnostic of dieselelectric propulsion for ships dialnet.

Understanding bearing failure a sound practice following a premature bearing failure is to send the failed bearing out for analysis to find out why it failed. Stage 2 signal appears at the first harmonic frequency of the bearing at 500 to 2,000 hz. Table 21 describes bearing failures, first assigning a general term to each type of failure, then adding more detailed classifications. The bottom portion of the cranks carrying the bronze bush bearings engage with the journal portion of the pins which form integral part of bull gears on either sides of the. One of the key issues in bearing prognostics is to detect the defect at its incipient stage and alert the operator before it. Azipod is an electric podded azimuth thruster produced by abb group. Bearing failure defects in the appearance of bearings are referred to as bearing failures. Rolling bearings handbook and troubleshooting guide raymond a. This booklet is intended as a guide to bearing maintenance, with the main consideration being onsite bearing maintenance. Failure to follow procedure will damage the bearing andor seals during installation. Note that the ends of the rollers start to spall first while the. Rolling bearing damage recognition of damage and bearing.