ESP Mechanical Shaft Seals: Trials and Tribulations of Lab Testing

2021 ◽  
Author(s):  
John W. Sheldon ◽  
Francisco Alhanati ◽  
Jared Schoepp
Keyword(s):  
System Reliability ◽  
Influential Factors ◽  
Operating Conditions ◽  
Test Apparatus ◽  
Interesting Phenomenon ◽  
Factors Affecting ◽  
Operational Conditions ◽  
Wide Range ◽  
Design Selection ◽  
Shaft Seals

Abstract Mechanical Shaft Seals (MSSs) are critical sub-components in Electric Submersible Pump (ESP) Seal Chamber Sections (SCSs), as they are the primary barriers used to isolate wellbore fluids from the motor oil. However, several ESP operators have observed relatively high MSS failure rates in certain applications, resulting in significant impacts on overall ESP system reliability and operational costs. In some cases, during teardowns, wellbore fluids were found in the lower chambers of the SCS, without any signs of damage to the MSSs or the bags/bellows in the SCS. Thus, to improve the run-life of ESP systems in their applications, operators identified the need to better understand the main influential factors affecting leakage rates through the MSS, including factors associated with the MSS characteristics and its operational conditions. To accomplish this, a test apparatus was built to allow the testing of MSSs in a wide range of operational conditions. This paper summarizes the technical challenges and key learnings that arose from building and commissioning such a test apparatus, as well as conducting several tests on multiple MSSs of a single design. Through commissioning of the test apparatus and subsequent testing, several limitations of the apparatus were identified and corrected through upgrades. Many of these upgrades were related to ensuring reasonably accurate measurement of the leakage rate through the MSSs, in both directions. Unexpected behaviours of the MSS were also observed during some tests. One example is the interesting phenomenon of reverse-pumping where, under certain conditions, leakage occurs in the opposite direction of the applied differential pressure. Finally, questions arose about the importance of certain aspects of quality control for MSSs and/or SCS assembly procedures. The above effort to build and commission a MSS testing apparatus has resulted in unique insight into shaft seal behaviour and continues to shine light on gaps in the industry understanding of factors affecting leakage through MSSs. It certainly provides evidence that there are many ‘unknown unknowns’ about MSS performance under challenging downhole operating conditions, and that the effort is worth continuing to support better MSS design/selection, and SCS assembly, as part of improving ESP system reliability.

Narrower System Reliability Bounds With Incomplete Component Information and Stochastic Process Loading

2017 ◽  
Vol 17 (4) ◽  
Author(s):  
Yao Cheng ◽  
Daniel C. Conrad ◽  
Xiaoping Du
Keyword(s):  
System Reliability ◽  
Operating Conditions ◽  
Reliability Estimation ◽  
Design Stage ◽  
Shared Environment ◽  
Limited Information ◽  
Reliability Bounds ◽  
Component Design ◽  
Wide Range ◽  
Stochastic Load

Incomplete component information may lead to wide bounds for system reliability prediction, making decisions difficult in the system design stage. The missing information is often the component dependence, which is a crucial source for the exact system reliability estimation. Component dependence exists due to the shared environment and operating conditions. But it is difficult for system designers to model component dependence because they may have limited information about component design details if outside suppliers designed and manufactured the components. This research intends to produce narrow system reliability bounds with a new way for system designers to consider the component dependence implicitly and automatically without knowing component design details. The proposed method is applicable for a wide range of applications where the time-dependent system stochastic load is shared by components of the system. Simulation is used to obtain the extreme value of the system load for a given period of time, and optimization is employed to estimate the system reliability bounds, which are narrower than those from the traditional method with independent component assumption and completely dependent component assumption. Examples are provided to demonstrate the proposed method.

Formaldehyde Formation in Large Bore Engines Part 2: Factors Affecting Measured CH2O

1999 ◽  
Vol 122 (4) ◽  
pp. 611-616 ◽  
Author(s):  
Daniel B. Olsen ◽  
Charles E. Mitchell
Keyword(s):  
Natural Gas ◽  
Air Pollutant ◽  
Operating Conditions ◽  
Factors Affecting ◽  
Natural Gas Engines ◽  
Spark Timing ◽  
Wide Range ◽  
Hazardous Air Pollutant ◽  
Relationship Of ◽  
The Impact

Current research shows that the only hazardous air pollutant of significance emitted from large bore natural gas engines is formaldehyde CH2O. A literature review on formaldehyde formation is presented focusing on the interpretation of published test data and its applicability to large bore natural gas engines. The relationship of formaldehyde emissions to that of other pollutants is described. Formaldehyde is seen to have a strong correlation to total hydrocarbon (THC) level in the exhaust. It is observed that the ratio of formaldehyde to THC concentration is roughly 1.0–2.5 percent for a very wide range of large bore engines and operating conditions. The impact of engine operating parameters, load, rpm, spark timing, and equivalence ratio, on formaldehyde emissions is also evaluated. [S0742-4795(00)01004-8]

scholarly journals Removal of aniline from aqueous solutions by activated carbon coated by chitosan

2015 ◽  
Vol 5 (4) ◽  
pp. 610-618 ◽  
Author(s):  
Qian Liu ◽  
Lujie Zhang ◽  
Pan Hu ◽  
Ruihua Huang
Keyword(s):  
Activated Carbon ◽  
Aqueous Solutions ◽  
Ph Value ◽  
Operating Conditions ◽  
Optimum Operating ◽  
Order Kinetic ◽  
Factors Affecting ◽  
Adsorbent Dosage ◽  
Wide Range ◽  
Carbon Coated

In this work, activated carbon (AC) coated by chitosan was synthesized and characterized by Fourier transform infrared spectrophotometer and scanning electron microscope (SEM) techniques. The removal of aniline from aqueous solutions by AC coated by chitosan was investigated. The factors affecting the adsorption of aniline onto AC coated by chitosan, including the ratio of AC to chitosan, adsorbent dosage, pH value of solution, initial aniline concentration, and contact time were evaluated. These results showed that the optimum operating conditions were: the ratio of AC to chitosan = 0.5, adsorbent dosage = 0.2 g, and the adsorption of aniline from aqueous solutions had better removal in the concentration range of 20–50 mg/L. This adsorbent allowed high removal toward aniline in a wide range of pH. The equilibrium time was 100 minutes. The Freundlich model exhibited better correlation of the equilibrium adsorption data. The pseudo-second-order kinetic equation could better describe the kinetic behavior of aniline adsorption.

scholarly journals Identification of a Material–Lubricant Pairing and Operating Conditions That Lead to the Failure of Porous Journal Bearing Systems

2020 ◽  
Vol 68 (4) ◽  
Author(s):  
Guido Boidi ◽  
Stefan Krenn ◽  
Stefan J. Eder
Keyword(s):  
Mixed Lubrication ◽  
Operating Conditions ◽  
Maximum Temperature ◽  
Asperity Contact ◽  
Operational Conditions ◽  
Practical Applications ◽  
Custom Made ◽  
Wide Range ◽  
Lab Test ◽  
Wear Tests

AbstractIn this study, we perform accelerated wear tests with porous journal bearings (PJBs) on a lab test rig, providing statistically reliable results under realistic operational conditions. To this end, a custom-made tribometer consisting of 5 mechanically independent but centrally controlled units was used to test five identical bearings in parallel. The test parameters were tuned to promote enough wear under mixed lubrication by increasing the clearance gap and the radial load, while minimizing the bidirectional rotational speed. A wide range of lubricant and material combinations were evaluated, the vast majority of which performed excellently (i.e., negligible wear and low friction). Only one notable combination of a low-density iron bearing paired with a standard PAO-based lubricant failed when operating at low rotational speeds, exhibiting highly unstable frictional behavior and 10–20 times the typical wear in practical applications. An analysis of Stribeck curves, recorded periodically during the wear tests as a diagnostic tool, proved that this particular combination of materials and parameters failed to run in properly, with deteriorating tribological behavior over time. A direct relation between the total wear and the maximum temperature in the tribocontact during testing helped identify this pairing as the only one operating solely under mixed lubrication (high asperity contact), explaining the excessive wear. Graphical Abstract

scholarly journals Green Synthesis of Metallic Nanoparticles: Applications and Limitations

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 902
Author(s):  
Pritam Kumar Dikshit ◽  
Jatin Kumar ◽  
Amit K. Das ◽  
Soumi Sadhu ◽  
Sunita Sharma ◽  
...  
Keyword(s):  
Green Synthesis ◽  
Metallic Nanoparticles ◽  
Environmental Science ◽  
Cost Effective ◽  
Operating Conditions ◽  
Synthesis Methods ◽  
Comprehensive Overview ◽  
Factors Affecting ◽  
Wide Range ◽  
Range Of Functions

The past decade has witnessed a phenomenal rise in nanotechnology research due to its broad range of applications in diverse fields including food safety, transportation, sustainable energy, environmental science, catalysis, and medicine. The distinctive properties of nanomaterials (nano-sized particles in the range of 1 to 100 nm) make them uniquely suitable for such wide range of functions. The nanoparticles when manufactured using green synthesis methods are especially desirable being devoid of harsh operating conditions (high temperature and pressure), hazardous chemicals, or addition of external stabilizing or capping agents. Numerous plants and microorganisms are being experimented upon for an eco–friendly, cost–effective, and biologically safe process optimization. This review provides a comprehensive overview on the green synthesis of metallic NPs using plants and microorganisms, factors affecting the synthesis, and characterization of synthesized NPs. The potential applications of metal NPs in various sectors have also been highlighted along with the major challenges involved with respect to toxicity and translational research.

Design Improvements on a Bipolar Plate With Passive Water Management Using the Biomimetic Design Method

2010 ◽  
Author(s):  
Ji Ke ◽  
J. S. Wallace ◽  
L. H. Shu
Keyword(s):  
Water Management ◽  
Liquid Water ◽  
Design Method ◽  
Operating Conditions ◽  
Test Apparatus ◽  
Design Elements ◽  
Biomimetic Design ◽  
Flow Channels ◽  
Biological Phenomena ◽  
Wide Range

Liquid water build up in the cathode flow channels of a polymer electrolyte membrane fuel cell (PEMFC) can limit performance. A mechanism that removes accumulating liquid water continuously from the flow channels is required. While a number of water management strategies have been demonstrated, the search for improvements continues. This paper describes a novel technique of using biomimetic design to systematically generate a passive water management system concept for PEMFCs. Studies have shown that biology is a good source of analogies for engineering design. We believe that biomimetic design is an effective design methodology for PEMFC designs due to several common characteristics of biological systems, such as efficient use of material and energy, a self-regulating characteristic, and high tolerance to a wide range of operating conditions. A passive water management solution was generated based on two biological phenomena identified using the biomimetic design method. The biological phenomena inspired use of design elements such as random abrasions and polyethersulfone strands to remove water from the flow channels. The design was demonstrated on a simple test apparatus with low air flow rates and low inlet pressure. Preliminary experiments with the test apparatus have shown total recovery from flow channel catastrophic flooding within seconds. The present paper discusses the biomimetic design process, implementation, and prototype results.

Analysis of Thermal Damage in the High-Speed Foil Bearing

2017 ◽  
Vol 260 ◽  
pp. 266-277 ◽  
Author(s):  
Grzegorz Żywica ◽  
Paweł Bagiński ◽  
Artur Andrearczyk
Keyword(s):  
High Speed ◽  
Thermal Analyses ◽  
Experimental Tests ◽  
Significant Rise ◽  
Operating Conditions ◽  
Factors Affecting ◽  
Foil Bearings ◽  
Foil Bearing ◽  
Wide Range ◽  
Heavy Loads

The article discusses experimental research and simulation testing on prototypical foil bearings. All experimental tests were conducted on a special test rig which makes it possible to operate in various conditions and within a wide range of speeds. As a result of the study, it turned out that adverse operating conditions caused almost instant bearing damage, accompanied by a significant rise in temperature. The main factors affecting the durability of foil bearings were material covering mating surfaces, bearing geometry, way of assembling the bearing, rotational speed and load. To better understand the physical phenomena occurring in foil bearings, a numerical model has been developed which allowed carrying out thermal analyses. The analysis of heat flow in the bearing's structure showed that, because of the system geometry, significant problems with proper removal of large amounts of heat continued to be experienced, which may have led to an accelerated rate of fatigue damage and shorter bearing life. This phenomenon can occur in bearings operating under tough conditions (e.g. at low speeds or under heavy loads). The research showed that the development of a new foil bearing is a very difficult task and requires many aspects to be taken into account, including the aspects directly related to the operation of the bearing itself, as well as those related to the rotor's operation and characteristics of the machine.

scholarly journals Critical Station Practical Capacity on a Bus Rapid Transit Line with Nonstopping Buses

2021 ◽  
pp. 036119812199939
Author(s):  
Jonathan M. Bunker ◽  
Faheema Hisham
Keyword(s):  
Quality Of Service ◽  
High Capacity ◽  
Operating Conditions ◽  
Bus Rapid Transit ◽  
Rapid Transit ◽  
Operational Conditions ◽  
Capacity Model ◽  
Wide Range ◽  
Transit Capacity

Bus rapid transit (BRT) can offer transit mobility to meet growing travel demands by cost-effectively providing high capacity and quality of service. It is adaptable to a wide range of operating conditions and technological advancements. Stations are elements that typically control BRT line capacity, so it is essential to understand the operation of any potentially critical station to understand and manage the facility. The Transit Capacity and Quality of Service Manual (TCQSM) provides the standard methodology for capacity estimation. However, that model does not account for important operational aspects including the stochastic nature of many parameters beyond dwell time, along with nonstopping buses’ capacity, the degrees of saturation of the stopping and nonstopping bus streams, and the upstream average waiting time and queue length of stopping buses. We adapted the theory developed by Hisham et al. for an onstreet bus stop, to reflect the operational conditions of a BRT station and to account for these aspects. This new reliability-based capacity model tailored to BRT facilities provided superior insight into station bus capacity and quality of service to the TCQSM model.

scholarly journals Model Predictive Control of a Double Effect Evaporator Via Simulation

2021 ◽  
Vol 28 (1) ◽  
pp. 49-63
Author(s):  
Duraid Ahmed ◽  
Ihal Abed
Keyword(s):  
Dynamic Behavior ◽  
Flow Rate ◽  
Material Balance ◽  
Temperature Response ◽  
Double Effect ◽  
Difficult Problem ◽  
Operating Conditions ◽  
Feed Concentration ◽  
Operational Conditions ◽  
Wide Range

This paper is a study of the dynamic behavior of the double effect evaporator on the basis of energy and material balance under unsteady state conditions inside the evaporator. The simulation process was based on a model for the intensification of tomato juice. The mathematical model was used to study the effect of operational conditions, namely, the temperature of the feed, the flow rate of the feed, and the feed concentration. The dynamic behavior of the open system was studied by measuring the temperature response of the evaporators to the change of the staging function in the temperature of the feed, the feed flow rate and the feed concentration in the rate of (±10%, ±20%).The proportionalintegral-derivative and model predictive controllers were applied to solve the difficult problem by determining the best operational conditions and avoid a sharp increase in temperature. Two methods are tested to control a wide range of operating conditions and simulation results show that there is good accuracy. The MPC controller is more accurate than the PID control and faster to reach the constant value.

Comparison of Deterministic and Linear Cosine Spatial Filtering of Transmission Electron Micrographs

1972 ◽  
Vol 30 ◽  
pp. 596-597
Author(s):  
David A. Ansley
Keyword(s):  
Spherical Aberration ◽  
Focal Length ◽  
Chromatic Aberration ◽  
Spatial Filter ◽  
Operating Conditions ◽  
Objective Lens ◽  
List Type ◽  
Spatial Filters ◽  
Transmission Electron ◽  
Wide Range

The coherence of the electron flux of a transmission electron microscope (TEM) limits the direct application of deconvolution techniques which have been used successfully on unmanned spacecraft programs. The theory assumes noncoherent illumination. Deconvolution of a TEM micrograph will, therefore, in general produce spurious detail rather than improved resolution.A primary goal of our research is to study the performance of several types of linear spatial filters as a function of specimen contrast, phase, and coherence. We have, therefore, developed a one-dimensional analysis and plotting program to simulate a wide 'range of operating conditions of the TEM, including adjustment of the:(1) Specimen amplitude, phase, and separation(2) Illumination wavelength, half-angle, and tilt(3) Objective lens focal length and aperture width(4) Spherical aberration, defocus, and chromatic aberration focus shift(5) Detector gamma, additive, and multiplicative noise constants(6) Type of spatial filter: linear cosine, linear sine, or deterministic

Sign in / Sign up

Export Citation Format

Share Document