Shaft Alignment Research Articles

A novel 4-DOF marine stern bearing support model considering discrete distribution effects

To address the issue of the traditional support model's inability to accurately describe the non-uniform dynamics behavior inside the bearing, this study proposes a novel 4-degree-of-freedom (DOF) bearing support model that incorporates the discrete distribution effects induced by the bi-directional misalignment and bending deformation of the journal. Additionally, a coupling algorithm is designed to study the interaction behaviors between the marine stern bearing lubrication performance and the shaft dynamics. Moreover, a full-size marine shaft alignment test rig for measuring dynamic bearing loads is designed to verify the validity of the present model. On this basis, the effects of different bearing models, rotational speeds, external loads, and bush elastic modulus on the shaft dynamic alignment and the static and dynamic characteristics of the stern bearing are investigated. The experimental results indicate that the 4-DOF model, which takes into account discrete distribution, exhibits a more precise prediction of the alignment characteristics of the shaft system, with a forecast error for the stern bearing load of 1.32%. Heavy loads or low rotational speeds significantly deteriorate the edge-loading effect and increase the stiffness and damping coefficient of the bearings. The bearing lubrication performance directly affects the alignment performance of the shaft system, particularly in low-speed conditions. A softer bush material can increase the minimum oil film thickness, carrying region, and damping coefficient, mitigate the phenomenon of edge-loading, and facilitate the vibration control of the shaft. Research results have made a great contribution to marine shaft alignment optimization and structure design.

Evaluating the safety of the redesigned shafting system following the propeller redesign aimed at enhancing CII and EEXI

In July 2023, the International Maritime Organization (IMO) set a target to achieve net-zero greenhouse gas emissions by 2050, introducing key measures such as the Energy Efficiency Design Index (EEDI), the Energy Efficiency Existing Ship Index (EEXI), and the Carbon Intensity Indicator (CII). The maritime industry explored adaptations, including engine de-rating, energy-efficient technologies, and propeller modifications, and beyond. This study assessed the safety implication of a redesigned shafting system, resulting in a propeller redesign to enhance the CII and EEXI on a 6500 TEU container ship built in 2006. Through an analysis of annual output per TEU from 2000 to 2015, the study focused on container ships built from 2005 to 2007 with high-output engines (9.4–9.5 kW/TEU). After selecting a sample ship, the study determined engine power limits according to the EEXI regulations and assessed their impact on the CII. Subsequently, the study redesigned the shafting system, performing torsional vibration calculations and shaft alignment analyses to ensure the safety of the modified system. While an enhanced CII rating was predicted, the tightening CII regulations imply this benefit may be short-lived, lasting approximately two years. Thus, additional measures are essential to prolong the improved CII rating.

Shaft alignment for rotary machines using wireless power transfer process: Foundations and design approach

The aim of this paper is to present the fundamentals of an original method of shaft alignment for rotating machines based on the principle of wireless power transfer (WPT) process. WPT alignment of shafts in rotating machinery is simple and more accurate than existing methods (conventional mechanical methods or Laser-optical method) and can result in reduced power consumption and minimized mean time between failures. Shaft alignment is an important factor in the proper functioning and longevity of machinery. Proper shaft alignment ensures that the rotating shafts of a machine are in a straight line and rotate on the same axis. This contributes to reducing the wear and tear on the bearings and other components of the machine, leading to improved reliability and longer service life. A high precision WPT alignment system has been designed with the primary coil placed in the driver machine, as an electrical motor, and the secondary coil placed in the driven machine, as a pump. The calculation of the magnetic interactions between both coils (primary and secondary coils), in particular the mutual inductance and coupling coefficient, perfectly explains deviations in the shaft (angular misalignment and parallel offset) and aligns entirely with measurement results, with a difference of approximately 4%. This new alignment method with magnetic interactions has proven effective in designing and implementing actual shaft alignment. WPT alignment offers precise shaft alignment tools for proper alignment of shafts and reduces troubleshooting issues.

Performance Evaluation of Hydrostatic Transmission Systems in Tidal Energy Conversion

The growing need for renewable energy has brought oceancurrent energy’s promise as a consistent and ecologically benign source front stage. One can effectively harness this energy with tidal energy conversion systems (TECS). This work examined the performance of a hydrostatic transmission (HST) system in a prototype tidal stream power producing configuration. Comprising a turbine simulator, hydraulic transmission, and permanent magnet synchronous generator (PMSG) with torque, power, and speed sensors, the experimental setup Under different torque settings, tests were performed to assess if the system could separate submerged components from those above sea level and improve rotational speed. According to the findings, the HST system has rather poor efficiency, averaging about 22%, even as it delivers the intended speed gain. Efficiency loss results from elements including hydraulic fluid viscosity, internal wear, and shaft alignment. These results highlight the need of more study to maximize HST systems for improved dependability and performance in tidal energy uses.

A Study on the Characteristics about Shaft Deflection According to the Change in Manufacturing Sequences

Recently, the amount of orders for large container ships based on eco-friendly fuel is increasing. Container ships have very different characteristics of cargo as comparing other type cargo carriers, having a unique arrangement of structural members. In this reason, the classification societies propose major governing conditions that affect independent shaft alignment calculations based on detailed analysis. In this study, the change in displacement around the shaft system, which occurs in the manufacturing process, was investigated using structural analysis modeling. The manufacturing process is divided into PE (Pre-erection), welding according to the erection sequences, lifting the block, setting on the dock, and finally reviewing the launching conditions. The results of this study, the displacement of the shaft system during the manufacturing stages were confirmed. The change in the number of block supports had the greatest effect on the change in deflection rather than the effect of welding heat, and the final results were similar to those of the PE condition. The shaft centering analysis can be predicted correct value in advance if the characteristics of deflection change according to the process are known, and accurate prediction can be made in a short time by using the proposed procedure.

High rate of avascular necrosis but excellent patient-reported outcomes after open reduction and internal fixation (ORIF) of proximal humerus fracture dislocations: should ORIF be considered as primary treatment?

Proximal humerus fracture dislocations, excluding 2-part greater tuberosity fracture dislocations, are rare injuries. Outcomes after open reduction and internal fixation (ORIF) of these injuries have not been well described in the literature. The purpose of this study was to report the radiographic and functional outcomes of patients who underwent ORIF of a proximal humerus fracture dislocation. All skeletally mature patients who underwent ORIF of a proximal humerus fracture dislocation between 2011 and 2020 were identified. Patients with isolated greater tuberosity fracture dislocations were excluded. The primary outcome was American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score at a minimum of 2 years. Secondary outcomes were the development of avascular necrosis (AVN) and reoperation rate. Twenty-six patients met the inclusion criteria. The mean age was 45 years (standard deviation 16), and 77% were men. Median time to reduction and surgery was 1 day (interquartile range [IQR] 1-5). There were 2 (8%) Neer 2-part fractures, 7 (27%) 3-part, and 17 (65%) 4-part fractures. Fifty-four percent (54%) involved the anatomic neck and 31% included a head-split component. Thirty-nine percent (39%) were anterior dislocations. The rate of AVN was 19%. The reoperation rate was 15%. Reoperations included removal of hardware (2), subscapularis repair (1), and manipulation under anesthesia (1). No patients went on to arthroplasty. ASES scores were available for 22 patients (84%) including 4 of 5 patients with AVN. The median ASES score at a mean of 6.0 years postoperatively was 98.3 (IQR 86.7-100, range 63.3-100) and was not different in those with or without AVN (median 98.3 vs. 92.0, P=.175). Only the presence of medial comminution and nonanatomic head shaft alignment on postoperative radiographs were associated with increased risk of AVN. Radiographic rates of AVN (19%) and reoperation (15%) were high in this series of patients undergoing ORIF of proximal humerus fracture dislocations. Despite this, none of the patients required arthroplasty, and patient-reported outcome scores at an average of 6 years postinjury were excellent, with a median ASES score of 98.5. ORIF should be considered as primary method of treatment in proximal humerus fracture dislocations not only in young patients but also middle-aged patients.

Balancing and Alignment Analysis of Vertical Wind Turbine Helix Type and Savonius Type

Electrical energy is one of the basic needs that is very important in life, in addition to the physiological development of living things, electricity is also an input for various efforts or activities in order to produce something for survival. Therefore, renewable energy that is more environmentally friendly and an inexhaustible source of energy is needed, namely wind energy. This power generator is called a wind turbine with a vertical shaft. This turbine converts wind energy into mechanical and electrical. In order to obtain a turbine design with high efficiency. It is also necessary to balance and align each component frame attached to the turbine rotor to produce a perfect/ideal rotation, so as to minimize the occurrence of vibrations caused by the imbalance. the results of calculations with the analytical method on Darrius Helix type obtained value = 0.125 Newton, and = 0.175 Newton, and the value of the angle = 63.43490. Alignment testing is carried out to determine the value of the misalignment between one blade with another blade. The results of the balancing test with the blade ballast obtained additional value, the blade D was 70 grams and the results from the plate addition test were obtained according to the calculation of the analytical method but also less than the maximum requiring additional load on the blade body to get blade A = 12 grams, blade B = 0, blade C = 40 grams, and a spoon D = 90 grams. For the results and discussion of the balancing and alignment method on the savonius type using the static balancing and alignment method using a dial indicator, the values obtained are in the fields A and B, the addition of mass is 59,007 grams and 59.007 grams with angles A and B 11.88 ° , and the value The misalignment deviation in the A, B and center planes is A: 4mm, B: 0.04mm, middle: 0.52mm, while the shaft alignment value is 0 because the value of the alignment of the shafts is the same or parallel.

Study of the Hull Structural Deformation Calculation Using the Matrix Displacement Method and Its Influence on the Shaft Alignment

The analysis of the influence of hull deformation on shaft alignment is predominately conducted using the finite element method (FEM), which is time-consuming, labor-intensive, and challenging to use for iterative hull design optimization. In this paper, hull deformation is separated into two parts—global deformation and local deformation, simplified to a single-span beam model and a grillage beam model, respectively—then solved using the matrix displacement method (MDM). Compared to FEM, the proposed method has a small calculation error, proving its correctness, while the calculation time is greatly reduced. The proposed method has been used to calculate the hull deformation of a ship under various conditions and evaluate its influence on shaft alignment. The results indicate that under certain conditions, the bearing reaction forces are constant, whereas the bearing pressure changes as a consequence of the change in shaft-to-bearing angle. The comparison between local rotation and shaft-to-bearing angle reveals that bearings in various positions follow distinct laws. We suggest that the shaft-to-bearing angle be used as an additional parameter in the evaluation of shaft alignment calculations. Moreover, when optimizing bearing pressure, bearings in different positions are affected differently by global and local deformation, and their optimization priorities are distinct.

Faults prevention for the gear coupling of the azimuth thruster L-drive through a study of shaft alignment measurements

The propulsion system is one of the most important systems in a vessel. It is considered critical, since if it fails, directly compromises the operation and safety. A common fault on the azimuth propulsion L-drive system is the gear coupling failure, where on the last stage of damage the shaft can broke causing propulsion loss. The two main reasons of this problem are the shaft misalignment and lack of gear coupling teeth lubrication. Through a specific alignment measurement procedure, performed on three different vessels and 17 azimuth thruster L-drive, this study will prove that the shaft alignment between motor and thruster is affected by the steering rotation of the azimuth system. The alignment changes due to steering position sometimes can be greater than alignment tolerance values, generating gear coupling damages. Then a specific procedure is proposed to measure, evaluate, and correct the alignment to prevent gear coupling failures and improve the system reliability.

40MW급 디젤 발전 장비의 실용적인 축계정렬 연구

Diesel power plants come in a variety of shapes, from moveable mini-power plants installed in 40-feet standard container boxes to large capacity power plants. The world's largest diesel power plant listed in the Guinness Book of World Records is Jordan's Amman Asian power plant, which produces a total of 573 MW of electric power. It consists of 38 units of 15MW capacity, and KEPCO achieved high profitability through the power plant. If a large capacity of 40MW clsss is applied, it will be newly listed in the Guinness Book of World Records even if only 15 units are constructed. Therefore, large-scale overseas orders for diesel power plants that require large capacity are expected in the future. The purpose of this study is to derive a practical offset by performing the shaft alignment analysis for large capacity 40MW shaft system, and to infer the change of offset for larger capacity shaft system through the comparison with the 30MW shaft alignment which is the result of the previous research. As a result, the practical offset of shaft system for the 40MW diesel power generation equipment was derived through the bearing influence assessment. From the comparison of shaft alignment between 30MW and 40MW, it is considered to be a complex offset to calculate the height of the engine bearing from 50MW class.

A real-time shaft alignment monitoring method adapting to ship hull deformation for marine propulsion system

Shaft alignment states are strictly stipulated in the marine propulsion system. However, there are relatively limited studies on shaft alignment monitoring and control considering the effects of ship hull deformation (SHD). SHD can be caused by wave load, loading, depth, speed, etc., and leads to various relative displacements at different shaft supporting points between the ship foundation and the support bearings of the propulsion system. It leads to shaft misalignment, increases shaft vibration and noise, and even endangers the safety of shaft system during the operation stages. To overcome this problem, a real-time shaft alignment monitoring method based on laser displacement sensors (SAMM/LDS) is proposed. Firstly, the defects of a present shaft alignment monitoring method based on eddy current displacement sensors (SAMM/ECDS) are analyzed when considering the effects of SHD. The structure and working principle of a shaft alignment monitoring system adapted to SHD (SAMS/SHD) are proposed. It consists of three sub-systems: the shaft alignment monitoring sub-system adapting to SHD (SAMSS/SHD), the present shaft alignment monitoring sub-system (SAMSS/P), and the shaft alignment correcting sub-system (SACSS). Based on SHD data-driven, SAMS/SHD can not only take advantage of SAMSS/P for long-time operations but also reflect SHD by exploiting the advantages of SAMSS/SHD. Secondly, SAMM/LDS is deduced. Two laser displacement sensors (LDS) are placed on the driving shaft and the driven shaft to reflect the spatial relative displacement and attitude information affected by SHD. Therefore, two reference coordinate systems are fixed at the center of LDS, and the coordinate expressions of their imaging points are derived using a 4 × 4 homogeneous coordinate transformation matrix. For reducing computing complexity in engineering applications, a simplified monitoring model is proposed for very small rigid-body rotational angularities. Finally, the effectiveness and testing accuracy of the SAMM/LDS is verified on a five-DOF platform which can simulate the effects of SHD. The SAMM/LDS can be used to realize real-time and high-precision shaft alignment monitoring for marine propulsion system which can adapt to the effects of SHD and so on. Based on the foundation of this research, compensation control algorithms to solve the misalignment effects deduced by SHD will be studied for marine propulsion system with resilient mounts in the next few years.

Machine learning performance comparison for main propulsive shafting systems alignment

The ship shaft alignment is crucial to achieve a high-performance propulsion system. This alignment is carried out, still in drydock, by adjusting the bearings' offsets. However, there are numerous available combinations sets of vertical offsets which results in good alignment final condition. Defining an optimum set of vertical displacements is costing shipyards a valuable time. Therefore, this work proposes the use of machine learning algorithms to predict if a given set of offsets, following the mandatory rules in force, should be implemented or not. In this manner, this paper presents a case study where a finite element model of an Anchor Handling Tug Supply (AHTS) vessel’ shaft line was assembled in order to obtain the bearings reactions, shaft line deflections, shear forces, bending moments and, finally, the influence coefficients matrix (ICM). Those data were used to feed machine learning (ML) models based on four different algorithms, namely, K-Nearest-Neighbors, Extremely Randomized Trees, Random Forest and Gradient Boosting in order to solve multiclass classification problems concerning the offset's set to be applied in the alignment of the shaft line. Results showed that the Gradient Boosting and Random Forest algorithms presented the best results, achieving up to 98.1% of precision in one of the 36 scenarios tested, and an average precision above 96.0%. Such results corroborated with the authors' proposal to implement ML techniques as a way to speed up the currently very time-consuming shaft alignment process.

Measurement of Vibration and Improving the Shaft Vibration Dynamics of Gear and Belt Drive Using a Vibration Analyzer

Rotating elements are essential components in the industrial sector, where vibration is a common occurrence. Vibration has its bad impacts, which include damages, disturbances, noise, etc. As a result, every industry must quantify the effect of vibration and keep it below a certain threshold. To study the effect of vibration, a system is developed that consists of power transmitting elements such as a belt-pulley mechanism, spur gear, ball bearing, shaft, and a motor for power production. This rotating element's vibration is analyzed by a vibration analyzer, which contains three types of sensors that measure the vibration characteristics along three axes (X, Y, and Z) at a particular point and return the vibration characteristics in waveform and spectrum at different points. This article describes the vibration of the shaft during shaft misalignment, mechanical looseness, and mass unbalancing. During this condition, the vibration level at a specific point crosses the ISO standard. After shaft alignment, mass balancing, and using damper materials, these vibration levels reduce to a certain level lower than those of the previous conditions, which have been studied in this paper. The vibration analyzer evaluates these vibration levels to determine whether or not the machinery is in optimal condition. This study provides analysis and design engineers with practical guidance for considering noise and vibration in gear and belt drives.

A novel pre-processing modelling method for the finite element analysis of the thermal deformation of large structures in the erection stage

The manufacturing process of ships and offshore structures comprises several stages, which include plate cutting, sub-assembly, block assembly, pre-erection, and erection. Accuracy and quality control management are crucial issues in the manufacturing process. Welding-induced distortion and deformation complicate the assembly stage in shipyards. Through conventional finite element (FE) analysis, the manufacturing process can be predicted and controlled up to the sub-assembly stage; however, applying the FE method to the stages between block assembly and erection is difficult. In this study, a new FE analysis method for predicting welding-induced thermal deformation of large blocks, which was difficult to predict with traditional methods, was proposed. In addition, based on this result, we developed a novel pre-processing modelling system that can automatically extract the erection weld lines and automatically divide blocks, which are necessary for the thermal deformation analysis of large blocks. Validation experiments confirmed the applicability of the proposed method to the shaft alignment of a container ship and LNG carrier, with industrial accuracy and quality control in the manufacturing process. Compared with existing methods, the proposed method increases the accuracy of the analysis and reduces the total pre-processing time.

Design and testing of a smart rubber stave for marine water-lubricated bearings

Abstract The water-lubricated bearing is mainly installed at the stern of the ship to support the rotation of the main shaft of the ship, which is an important component of the ship’s power plant. The rubber stave of the water-lubricated bearing acts as an elastic body, which can effectively suppress the rotational vibration of the rotating shaft and improve the shaft alignment effect. To monitor the operational status of the water-lubricated bearing at the stern of a ship, a design method of smart rubber stave for water-lubricated bearings is proposed in this article. According to the structure of the rubber stave, the packaging and protection form of the optical fiber, the forming process of the rubber stave, and the mechanical analysis were carried out to determine the distribution design principle of the fiber Bragg grating (FBG) in the rubber stave. Then, FBGs were packaged, protected, and implanted with an uneven distribution into the rubber stave to achieve force sensing in the bearing. With reference to the force state of the water-lubricated bearing during shipbuilding and ship operation, various types of condition monitoring tests were conducted on the smart rubber stave using an elastomer testing machine, which were to analyze the effects of load sizes, frequencies, and ambient temperatures. The tests showed that the FBGs in the rubber stave could monitor the static and dynamic loads of the bearing under the seawater environment or inland water environment below 30°C. This method can be used for the smart designing and online load condition monitoring of water-lubricated bearings.

META analysis of mobile bearing and fixed bearing unicondyle replacement for medial knee osteoarthritis

To evaluate of the clinical effects of mobile-bearing(MB) and fixed-bearing(FB) unicompartmental knee arthroplasty(UKA) in the treatment of knee osteoarthritis by Meta-analysis. The literature on FB UKA and MB UKA in the treatment of knee osteoarthritis in PubMed, CNKI, Wanfang, Cochrane and EMBASE database were searched by computer from January 2000 to April 2020. According to the inclusion and exclusion criteria, two authors were selected independently and the selected literature was evaluated for quality.After literature data were extracted, Review Manager 5.3 software was used to analyze knee function score, postoperative activity, revision rate, polyethylene wear rate, pad dislocation, aseptic loosening, postoperative pain, knee arthritis progression, mechanical shaft alignment of lower limbs, and imaging clarity line respectively. A total of 13 literatures were included in this meta-analysis, including 2 randomized controlled studies and 11 cohort studies. A total of 1 871 patients were included, including 913 in FB UKA group and 958 in MB UKA group. Meta analysis results showed that:postoperative knee joint function score[MD=-0.84, 95%CI(-1.46, -0.21), P=0.008] and postoperative knee joint range of motion [MD=-1.51, 95%CI(-2.84, -0.18), P=0.03] in FB UKA group were better than those in MB UKA group. Compared with FB UKA group, MB UKA group had a higher lower limb mechanical axis alignment rate[OR=2.08, 95%CI(1.27, 3.39), P=0.003], and the wear rate of polyethylene [OR=0.11, 95%CI(0.01, 0.91), P=0.04] was lower. There were no differences between two groups in the renovation rate [OR=1.16, 95%CI(0.75, 1.80), P=0.50), liner dislocation rate[OR=3.78, 95%CI(0.93, 15.29), P=0.06], aseptic loosening [OR=2.11, 95%CI(0.81, 5.51), P=0.13], postoperative pain[OR=1.13, 95%CI(0.37, 3.43), P=0.83], osteoarthritis progression[OR=1.28, 95%CI(0.67, 2.47), P=0.46)and imaging radiolucent line[OR=1.62, 95%CI(0.09, 30.22), P=0.75]. FB UKA has a higher postoperative functional score and range of motion.MB UKA has more advantages in the correction of lower limb mechanical axis, and the wear rate of polyethylene is also lower. There was no significant difference between the two groups in revision rate, dislocation of the liner, aseptic loosening, postoperative pain, progression of osteoarthritis, and postoperative translucency.

A Study on Shaft Alignment of Diesel Power Generation Equipment with 30MW Class Installed on LandA Study on Shaft Alignment of Diesel Power Generation Equipment with 30MW Class Installed on Land

디젤 엔진은 기동 정지 시간이 빠르고 좋은 내구성과 높은 신뢰성으로 발전용이나 대형 선박용에 적합할 뿐만 아니라 원자력 발전소의 비상 발전기 또는 도서지방과 같이 제한된 지역에서의 발전용 엔진으로 유용하게 활용되고 있다. 디젤 엔진을 이용한 세계 최대 발전소는 15㎿ 용량으로 구성된 요르단의 암만아시아 발전소이며 이를 통해 높은 수익을 경험한 바 있다. 본 연구의 목적은 디젤 발전소의 대규모 해외 수주에 대비하여 대용량인 30㎿ 급 디젤 엔진 및 발전기를 구동하는 축계에 대한 축계해석을 수행하고, 오프셋(offset)의 변화에 따른 베어링에 발생하는 하중의 영향을 분석하여 최적의 오프셋을 도출하는 것이라 할 수 있다. 최적의 오프셋이란 작업자의 실수 및 작업 횟수를 최대한 줄일 수 있고 발전기 및 엔진 제작업체의 제한조건을 모두 만족하는 복잡하지 않은 오프셋을 의미한다. 연구 결과 대용량 디젤 엔진 및 발전기를 구동하는 축계에서도 베어링 영향 평가를 통해 충분히 단순한 오프셋을 도출할 수 있게 됨을 확인하였다.

Application of Deep Reinforcement Learning to Predict Shaft Deformation Considering Hull Deformation of Medium-Sized Oil/Chemical Tanker

The enlargement of ships has increased the relative hull deformation owing to draft changes. Moreover, design changes such as an increased propeller diameter and pitch changes have occurred to compensate for the reduction in the engine revolution and consequent ship speed. In terms of propulsion shaft alignment, as the load of the stern tube support bearing increases, an uneven load distribution occurs between the shaft support bearings, leading to stern accidents. To prevent such accidents and to ensure shaft system stability, a shaft system design technique is required in which the shaft deformation resulting from the hull deformation is considered. Based on the measurement data of a medium-sized oil/chemical tanker, this study presents a novel approach to predicting the shaft deformation following stern hull deformation through inverse analysis using deep reinforcement learning, as opposed to traditional prediction techniques. The main bearing reaction force, which was difficult to reflect in previous studies, was predicted with high accuracy by comparing it with the measured value, and reasonable shaft deformation could be derived according to the hull deformation. The deep reinforcement learning technique in this study is expected to be expandable for predicting the dynamic behavior of the shaft of an operating vessel.

Indicator type device for aligning of pump shafts

An indicator centering device based on neodymium magnets is developed, which makes it possible to control the axial and radial clearances. The general methods of alignment used in production are considered. Keywords: shaft alignment, dial indicator, electric motor, pump, half-coupling gystomyasov@mail.ru

ANALISIS PENGARUH KELURUSAN POROS KOPLING POMPA HIDRAULIK TERHADAP VARIASI TEKANAN PADA PLTA MANINJAU

Vibration due to misalignment in the hydraulic pump is detected as the main problem of damage to the pump. Resolved a problem with the alignment of the pump, shaft alignment as an action in overcoming the problem. Vibration measurements are carried out during alignment and misalignment conditions by using a vibration measuring instrument, namely vibration analysis fluke 810. Voltage, current, electrical power, motor & pump rotation, and other operating parameters are observed. Vibration analysis is done by observing the velocity and frequency of the wave signal for alignment and misalignment conditions. Vibration analysis is performed using a comparison method to the ISO 10816-3 tester standard. Finally obtained an ideal vibration in the operation of hydraulic pumps based on the above standards.The method used to analyze using the tool RCFA (root cause failure analysis) which is an investigation process to determine the main causes of a failure mode. From the analysis, we concluded that the formulation RCFA rise broken of coupling.