Pump Assembly Research Articles

A study into the feasibility of using the oxygen-hydrocarbon engine 11D58M as a basis for development of a high-performance multifunctional gas-generatorless rocket engine with oxygen cooling

The paper presents results of engineering studies and research and development efforts at RSC Energia to analyze and prove the feasibility of using the mass-produced oxygen-hydrocarbon engine 11D58M with 8.5 ton-force thrust as a basis for development of a high-performance multifunctional rocket engine with oxygen cooling and 5 ton-force thrust, which is optimal for upper stages (US), embodying a system that does not include a gas generator. The multi-functionality of the engine implies including in it additional units supporting some functions that are important for US, such as feeding propellant from US tanks to the engine after flying in zero gravity, autonomous control of the engine automatic equipment to support its firing, shutdown, adjustments during burn and emergency protection in case of off-nominal operation, as well as generating torques for controlling the US attitude and stabilizing it during coasting, etc. Replacing conventional engine chamber cooling that uses high-boiling hydrocarbon fuel with the innovative oxygen cooling makes it possible to get rid of the internal film cooling circuits and eliminate their attendant losses of fuel, while the use of the oxygen gasified in the cooling circuit of the chamber to drive the turbo pump assembly permits to design an engine that does not have a gas generator. Key words: Multifunctional rocket engine, oxygen cooling, gas-generatorless design, upper stage.

Warranty Cost Estimation using K-Means Cluster Analysis for Automobile Industry: Technical Note

When a vehicle under warranty comes for service, the technician identifies the potential fault and the corresponding service is done. From the raw information of customer complaint, the complaint codes are identified and allocation of qualified technician involves considerable man hours and cost per hour for the technician to do the service. Around 1059 vehicles under warranty were studied starting from customer complaint to the study of warranty cost to the manufacturer. In this paper, initially, we present the results of classifying the complaint code master into several classes using K-means cluster analysis and subsequently cluster analysis for a specific component say, water pump assembly was carried out. Then, analysis of cost to the automobile manufacturer on warranty claims are also presented here.

Ontological model-based optimal determination of geometric tolerances in an assembly using the hybridised neural network and Genetic algorithm

Traditional Geometric tolerance allocation method assumes the parts of the assembly are purely rigid. Upon assembly and function, it is realised that the rigidity of the parts is non-ideal which leads to severe variations. Hence the performance of an assembly declines and is associated with the parts performance in the assembly. An assembly always experiences deformations due to internal and external forces/loads and drop in efficiency is critically observed. This paper proposes a methodology to predict such variations in assembly and integrate geometric tolerance design to it. First, the Ontological model of the assembly is predicted through Finite Element Analysis, and the near net shape of the assembly is obtained. Second, a set of features of an assembly which plays a vital role is selected, to determine the optimal geometric tolerances through the hybridised neural network and Genetic algorithm. Finally, a gear pump assembly is chosen, the proposed method is demonstrated. This method will be useful for design and new product development engineers in reducing the assembly variations and associated manufacturing cost.

Recent paradigm shift in the assembly of bacterial tripartite efflux pumps and the type I secretion system.

Tripartite efflux pumps and the type I secretion system of Gram-negative bacteria are large protein complexes that span the entire cell envelope. These complexes expel antibiotics and other toxic substances or transport protein toxins from bacterial cells. Elucidating the binary and ternary complex structures at an atomic resolution are crucial to understanding the assembly and working mechanism. Recent advances in cryoelectron microscopy along with the construction of chimeric proteins drastically shifted the assembly models. In this review, we describe the current assembly models from a historical perspective and emphasize the common assembly mechanism for the assembly of diverse tripartite pumps and type I secretion systems.

Flexibility of Free and AcrB-Bound AcrA in the AcrAB-TolC Multidrug Efflux Pump of Escherichia coli Determined using 3D PMFs

Key components of the emerging global epidemic of antibiotic resistance are the multidrug efflux pumps of pathogenic, Gram-negative bacteria, which span the periplasmic region between the inner and outer membranes of the cell. These protein complexes are an innate resistance mechanism, removing harmful antibiotics from bacteria. Until 2014 many aspects of the mechanisms for pump activity remained elusive due to the lack of structural data. Since then several increasingly detailed electron microscopy maps of an entire efflux pump complex, AcrAB-TolC, have been resolved, resulting in atomic-level structural models. Using these new models, we performed molecular dynamics simulations to study one of the key components of the protein complex, AcrA, which connects the inner-membrane-bound AcrB to the outer-membrane-bound TolC. We determined the flexibility of free AcrA by calculating a three-dimensional potential of mean force (PMF) focused on three angles that govern AcrA's conformational dynamics. AcrA shows a wide range of accessible orientations, with two main energy basins separated by a low (< 4 kT) barrier, consistent with previously reported equilibrium simulations. The conformation in one of the basins is similar to the AcrB-bound state, suggesting that assembly proceeds by conformational selection. Additional 2D PMFs of AcrA monomers bound to AcrB reveal differences in flexibility at the two distinct binding sites on AcrB, similar to the TriABC efflux pump, which contains a heterodimer membrane fusion protein where the two subunits exhibit unique properties and play different roles in efflux activity (Weeks et al. Mol. Micriobio. 2015). Lastly, equilibrium simulations of wild-type and mutant AcrA monomers elucidate the role of its two terminal domains in pump assembly.

Characterization of crosslinked hard gelatin capsules for a structural assembly of elementary osmotic pump delivery system

The objective of this study was to characterize the crosslinked hard gelatin capsules (HGCs) for use as a structural assembly of elementary osmotic pumps (EOP). HGCs were crosslinked in formaldehyde vapor for 6, 12, and 24 h. Weight loss after immersing in various mediums, water soluble protein fraction, loss on drying, and formaldehyde residue were investigated. Fourier transform infrared (FTIR) spectra were used to detect the crosslinking formation. The EOP capsules were prepared for delivery of diltiazem hydrochloride (DIL HCl) and ambroxol hydrochloride (AMB HCl), which are freely and sparingly water soluble drugs, respectively. Physicochemical stability of storage crosslinked HGC shells was investigated. All crosslinked HGC shells were water insoluble. FTIR spectra exhibited intermediate lysine methylol and arginine methylol peaks. Storage time increased, moisture content increased and formaldehyde residue decreased. The developing EOP capsules were more appropriate for delivery of high water soluble rather than low water soluble drug. EOP capsule contained 100 mg DIL HCl using HGCs crosslinked for 12 h provided release profiles for 12 h with a lag time of 2.6–3.1 h. It was also found that DIL HCl EOP capsules prepared using crosslinked HGC shells stored for 90 days maintained the similar drug release profiles. AMB HCl EOP capsules exhibited low drug release. In summary, the crosslinked HGCs were applicable as a structural assembly of the osmotic controlled drug delivery system.

Analysis of the Leakage-Flow-Induced Vibration of a Slip Joint in a Jet Pump of a Boiling Water Reactor

The purpose of this analysis is to evaluate the structural integrity of the jet pump assembly of a BWR during the performance of its operational and safety functions. The natural frequencies and vibration modes of the jet pump assembly immersed in water were determined. It was observed that the fourth mode shape was torsional, and its associated resonance frequency was 41.82 Hz. Also, the vibration induced by the flow in the leakage of the slip joint was analyzed with an axisymmetric model. The gap of the slip joint was varied from 0.2 mm until 0.65bmm. A gap between 0.6 and 0.64, would cause flow-induced vibration because this excitation frequency matches with the fourth natural frequency of the jet pump assembly. The above was carried out using computational fluid dynamics, as well as the finite element method, with ANSYS Structural and ANSYS Fluent codes.

Solar PV Fed Induction Motor Drive Using Modified SEPIC Converter

Nowadays for energy generation solar PV based system has came up as an important alternative. A solar PV fed water pumping system using an induction motor drive has been discussed in this paper. Solar PV array, modified SEPIC DC-DC Converter, a three phase voltage source inverter and a motor pump assembly are the main parts of the water pumping system. In a solar array fed water pumping system there are two stages. The first stage is to control the duty ratio of the dc-dc modified SEPIC converter to extract the maximum power from the Solar PV array. Under varying irradiance and temperature conditions, INC control method is utilized for maximum power point tracking (MPPT) of PV systems to control the duty ratio. In the second stage, switching pulses of the VSI is controlled by v/f controller based on the sinusoidal pulse width modulation. The frequency of SPWM is controlled for controlling the stator frequency of the IM.

Improvement of mud pump valve

The valve assembly is the weak point of the drilling pump. The analysis of the reasons for the failure of the hydraulic part of the drilling pump was carried out, it was shown that the valve assembly of the drilling pump accounts for a significant part of the failures. A three-dimensional geometric model of the valve assembly and a finite-element model of the valve assembly on its basis are developed. According to the results of the calculation, the effect of changing the inclination angle of the axis of the guide tray to the axis of the landing hole in the valve seat on the stress-strain state of the valve assembly was determined. To exclude axial deviations, an improvement in the valve is suggested by changing the design of the upper guide bushing body, which will increase the durability and reliability of the mud pump assembly by self-centering the pylon and the polyurethane seal.

Motion Analysis System (MAS) for production and ergonomics assessment in the manufacturing processes

Nowadays the Smart Factories operating within the Industry 4.0 revolution, require more and more reliable, fast and automatic tools for production analysis and improvement. Manufacturing companies, in which the human labour has a crucial role, need instruments able to manage complex production systems in terms of resource utilization, product mix, component allocation and material handling optimization.In this context, this work presents an original hardware/software architecture, Motion Analysis System (MAS), aimed at the human body digitalization and analysis during the execution of manufacturing/assembly tasks within the common industrial workstation. MAS is based on the integration of the Motion Capture (MOCAP) technology with an ad hoc software developed for productive and ergonomic analysis of the operator during his work. MAS hardware integrates a network of depth cameras initially developed for gaming (Microsoft Kinect v2™, conceived for markerless MOCAP) and now used for industrial analysis, while an original software infrastructure is programmed to automatically and quantitatively provide productive information (human task analysis in terms of time execution and used space within the workplace, movements of hands and locations visited by the operator) and ergonomic information (full body analysis implementing all the internationally adopted indexes OWAS, REBA, NIOSH and EAWS). This double perspective makes MAS a unique and valuable tool for industrial managers oriented to the workplace analysis and design (in terms of productivity) without neglecting the operator health. This proposed contribution ends with a real industrial application analysing a water pump assembly station: the system setup is discussed and the key results obtained adopting MAS are presented and analysed.

基于Gabor和灰度共生矩阵混合特征叶片泵装配质量检测

基于Gabor和灰度共生矩阵混合特征叶片泵装配质量检测

Virtual postural assessment of an assembly work in a small scale submersible pump manufacturing industry.

Depletion of groundwater has increased the depth of bore wells drilled to meet water requirements. Water from these bore wells are accessed by operating submersible pumps with multi-stages. The number of stages of submersible pump directly depends upon the depth of bore well. Health-related risk such as Musculoskeletal Disorders (MSDs) arises during the manual assembly of these pumps in an awkward posture. The objective of this paper is to eliminate or reduce risk in the manual assembly of submersible pumps using virtual postural analysis. Secondary objective is to redesign the existing workstation incorporating ergonomic interventions. It reports a case study in which postural analysis is carried out with the help of Rapid Upper Limb Assessment (RULA) method. It is observed that inserting the stage casing weighing around 1.5 Kg through top end of the shaft is the awkward working posture involving a flexion of the arm about 152°. RULA score (7) indicate a high level of risk exists in the workstation, calling for investigate and change the working posture immediately. In order to reduce this risk, a redesigned workstation has been proposed. This study results help in minimizing the awkward postures, thereby reducing the health-related risk. This will also increase the efficiency of the worker and his productivity.

Time and Motion Study Methods for Manufacturing a Pump

The purpose of the study was to compare conventional time study method and MOST analysis on oil pump assembly in a manufacturing company. The results showed that the time study resulted in 0.239 minutes and MOST resulted in 0.18 minutes.

Dynamics of Intact MexAB-OprM Efflux Pump: Focusing on the MexA-OprM Interface

Antibiotic efflux is one of the most critical mechanisms leading to bacterial multidrug resistance. Antibiotics are effluxed out of the bacterial cell by a tripartite efflux pump, a complex machinery comprised of outer membrane, periplasmic adaptor, and inner membrane protein components. Understanding the mechanism of efflux pump assembly and its dynamics could facilitate discovery of novel approaches to counteract antibiotic resistance in bacteria. We built here an intact atomistic model of the Pseudomonas aeruginosa MexAB-OprM pump in a Gram-negative membrane model that contained both inner and outer membranes separated by a periplasmic space. All-atom molecular dynamics (MD) simulations confirm that the fully assembled pump is stable in the microsecond timescale. Using a combination of all-atom and coarse-grained MD simulations and sequence covariation analysis, we characterized the interface between MexA and OprM in the context of the entire efflux pump. These analyses suggest a plausible mechanism by which OprM is activated via opening of its periplasmic aperture through a concerted interaction with MexA.

Adaptor protein mediates dynamic pump assembly for bacterial metal efflux

Multicomponent efflux complexes constitute a primary mechanism for Gram-negative bacteria to expel toxic molecules for survival. As these complexes traverse the periplasm and link inner and outer membranes, it remains unclear how they operate efficiently without compromising periplasmic plasticity. Combining single-molecule superresolution imaging and genetic engineering, we study in living Escherichia coli cells the tripartite efflux complex CusCBA of the resistance-nodulation-division family that is essential for bacterial resistance to drugs and toxic metals. We find that CusCBA complexes are dynamic structures and shift toward the assembled form in response to metal stress. Unexpectedly, the periplasmic adaptor protein CusB is a key metal-sensing element that drives the assembly of the efflux complex ahead of the transcription activation of the cus operon for defending against metals. This adaptor protein-mediated dynamic pump assembly allows the bacterial cell for efficient efflux upon cellular demand while still maintaining periplasmic plasticity; this could be broadly relevant to other multicomponent efflux systems.

ASSESSMENT AND PREDICTION OF INDUSTRIAL WORKERS’ FATIGUE IN AN OVERHEAD ASSEMBLY JOB

This paper intends to predict time-related fatigue experienced among workers involved in the overhead assembly of submersible pumps. Borg’s CR-10 scale, the Samn-Perelli fatigue scale (SPFS), and dimensions of the Swedish occupational fatigue inventory (SOFI) were used to assess and predict fatigue. The results of a temporal analysis indicate that fatigue levels in this type of job increase throughout the work at a diminishing rate. Exploratory analysis revealed that Borg’s CR-10 scale is more reliable than SPFS in predicting fatigue. It was also observed that the physical discomfort dimension of SOFI is the predominant one for predicting fatigue in the selected task. Older and more experienced groups of workers showed significantly increased fatigue, while body mass index (BMI)- based groups did not show such differences.

Fuzzy control applied to water distribution systems with a view to reducing the waste of water and energy

This paper presents an application of fuzzy control technique in order to control pressure at entrance of a Water Distribution Pilot Network (RPDA, for its acronym in spanish), mesh with several points of consumption. Same is pressurized by a pump and motor assembly has power variation, which makes it difficult to stabilize control. Fuzzy controller implemented in system selects an optimum condition of operation regarding pressures available and engine output while maintaining pressure for network to meet demand. Evaluation of operating system energy gain with controller action was performed in comparison with operating system without control. Based on these results, fuzzy controller was satisfactory in controlling operating pressure during operation of distribution network.

An appraisal of physicochemical parameters and some trace metals at the disposal points of five industrial effluents in Trans-Amadi Industrial Area of Port Harcourt, Nigeria

Industrial effluent samples collected from the disposal point of five different companies in Trans-Amadi industrial area of Port Harcourt were analyzed to investigate effect on the environment. The analyzed effluent samples showed results of the physicochemical parameters and trace metals in the ranges : (pH 3.60 - 6.90), electrical conductivity (406.00 – 722.00 μs/cm), total dissolved solid (194.00-347.00 mg/l); total suspended solid (>1067.00), chloride (14.20-151.10mg/l), sulphate (20.40-25.30 mg/l), nitrate (3.00-3.20 mg/l), total organic carbon (4.57-1556.00 mg/l), chemical oxygen demand (20.00-6225.00 mg/l), iron (1.26-1.68 mg/l), zinc (0.02 mg/l), copper (0.06 mg/l), lead (0.38mg/l), nickel (0.56-0.93mg/l), cadmium (0.09-0.34mg/l), chromium (0.19 mg/l) and sodium (11.45-20.77mg/l). The results obtained were compared with World Health Organization and United State Environmental Protection Act (USEPA), maximum permissible limits. Results showed that pH, chloride, conductivity and total organic carbon values of samples from three industries were above the maximum permissible limit while TSS values of samples from the five industries were above specification. Only one Industry produced an effluent with a chemical oxygen demand within the allowable limit. Some heavy metals like Nickel, Cadmium, and Chromium were also above the USEPA maximum permissible limit. Total suspended solids were determined using Pressure Millipore Vacuum Pump Assembly (NACE TM-01-73), Concentrations of Chloride, Sulphate, Nitrate, Total organic carbon (TOC) and Chemical Oxygen Demand (COD) were determined using a DR 2800 Spectrophotometer. Heavy metals were determined using Atomic absorption spectrometer (Perkin–Elmer model 2280/2380 model). Keywords: Heavy metals, Industrial effluents, Pollution, Spectrophotometer, Physicochemical, Concentration

Design and Experiment Study of High Power Automobile Water Pump Based on CFD

A high power automobile cooling water pump is designed and developed based on the theory of centrifugal pump design and computational fluid dynamics (CFD). The structure of the automobile cooling water pump adopts a curved guide rib structure, so as to avoid the dry friction of the automobile cooling water seal of the pump. The structural elements and flow field of the automobile cooling water pump assembly are optimized by simulation analysis. The peak efficiency of the automobile cooling water pump assembly is more than 51%, the automobile cooling water pump performance has been significantly improved. The effective methods and means of product verification have been developed to ensure the high reliability and durability of the automobile cooling pump assembly.

Reviving Antibiotics: Efflux Pump Inhibitors That Interact with AcrA, a Membrane Fusion Protein of the AcrAB-TolC Multidrug Efflux Pump.

Antibiotic resistance is a major threat to human welfare. Inhibitors of multidrug efflux pumps (EPIs) are promising alternative therapeutics that could revive activities of antibiotics and reduce bacterial virulence. Identification of new druggable sites for inhibition is critical for the development of effective EPIs, especially in light of constantly emerging resistance. Here, we describe EPIs that interact with periplasmic membrane fusion proteins, critical components of efflux pumps that are responsible for the activation of the transporter and the recruitment of the outer-membrane channel. The discovered EPIs bind to AcrA, a component of the prototypical AcrAB-TolC pump, change its structure in vivo, inhibit efflux of fluorescent probes, and potentiate the activities of antibiotics in Escherichia coli and other Gram-negative bacteria. Our findings expand the chemical and mechanistic diversity of EPIs, suggest the mechanism for regulation of the efflux pump assembly and activity, and provide a promising path for reviving the activities of antibiotics in resistant bacteria.