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A study was carried out to investigate and enhance the effects of friction stir welding on the mechanical characteristics of a flange composed of 6061-T3 aluminum alloy. The pipes possess an outer diameter and wall thickness of 6 mm, while the plates are sized at 100 x 100 × 6 mm. Nine unique experiments were planned using the Taguchi orthogonal array method, with the welding tool remaining constant. Three independent variables (travel speed, rotation speed, and shoulder diameter) were altered at three different levels for each variable. The research analyzed the influence of various FSW factors on the weld flange joint. Analysis of variance (ANOVA) and grey relational analysis (GRA) were employed to determine the impact of each FSW underwater parameter. Moreover, the statistical Taguchi technique (TM) was used to predict the optimal combination of welding parameters to improve tensile properties, including tensile strength (UTS), yield strength (YS), elongation (EI%), and bending load (BL) of welded joints. Additionally, the actual tests demonstrated a high level of agreement with the results obtained from the proposed mathematical model. The validation results obtained indicate that the optimization method is a dependable tool for enhancing the quality responses of friction stir welding.

To enhance the uplift capacity and facilitate the installation of multi-row perfobond connectors at shallow burial depths, this study puts forward a novel notched T-perfobond connector. The design incorporates an integrated flange at the bottom of the connector and a notch at the edge of the hole. Through pull-out model tests on four notched T-perfobond connectors, this research investigates their failure mechanisms and pull-out capacities. Utilizing the explicit dynamics method in ABAQUS, a finite-element model of the pull-out resistance test for notched T-perfobond connectors is established and verified against experimental data. Furthermore, a detailed parametric analysis involving 54 models is conducted, examining crucial parameters such as rib dimensions, hole geometry, flange size, notch width, bar diameter, and material properties. Based on the combined experimental and numerical results, this paper assesses the suitability of current formulas for calculating the pull-out capacity of perfobond connectors and proposes a refined calculation method specifically for notched T-perfobond connectors. All the findings reported in this paper can serve as a reference in the design and construction of composite structures. [ABSTRACT FROM AUTHOR]

The flange joint is an important connection in steel tube structures. In this paper, 11 groups of flange joint tests were conducted to investigate the influences of tube diameter, flange plate thickness, the distance from the bolt to the tube centroid, bolt numbers and material strength on the mechanical behavior. One of two failure modes in tests is that the excessive plastic deformation on the flange plate makes the flange plate lose the bearing capacity; the other is that the steel tube yield makes the joints fail. The results show that the calculating method for flange joint in Chinese design code is so safe that amplifying the calculating results of the code by 1.2 times would be closer to the bearing capacity of specimens. For a flange joint with different tube diameters, thickening the flange plate of thinner tube or thinning the flange plate of another tube are effective to ensure the deformations on both sides of the flange plates are equivalent. The ratio of the bearing capacity of the steel tube to that of flange plate should be greater than 1.7. And the thickness of the flange plate should be thicker than 14mm to reduce the deformation caused by cutting, drilling and welding during manufacturing. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) is gaining traction as a preferred technique due to its potential to reduce heat input and enhance the mechanical properties of welded joints. However, the path to commercializing FSW for flange joints is not without challenges. Two primary obstacles are the complexity of the welding path and the intricate design requirements for the fixtures. These factors contribute to the difficulty in determining the ideal weld settings and process parameters, which are critical for achieving optimal results. The current study addresses these challenges by applying FSW to flange joints using custom-engineered fixtures. These fixtures are meticulously designed to hold the pipes and plates securely during the welding process. The focus of the research is on optimizing the multi-performance characteristics of FSW for Al 6063 flange joints through the hybrid Grey-based Taguchi method. The integrity of the weld joint is assessed by examining various mechanical properties within the weld zone, including rotation speed, travel speed, tool profile, and shoulder diameter. The study identifies the optimal parameter settings for the FSW process: a rotation speed of 3000 rpm, a travel speed of 3 mm/min2, a shoulder diameter of 20 mm, and a conical tool profile. Under these ideal conditions, the welded material exhibited a tensile strength of 170.169 MPa, a hardness of 63.7709 HV, and a corrosion rate of 0.022 mm/year. These findings underscore the effectiveness of the optimized FSW process in producing robust and durable flange joints. [ABSTRACT FROM AUTHOR]

During the major overhaul of a chemical plant, the pipelines were disassembled and cleaned. Upon reinstallation, an air-tightness test discovered that the flange of the tandem mixer had cracked at the 304 stainless steel (SS) welding joint, affecting normal production. In the present paper, the microstructure of the weld joint was analyzed using SEM equipped with an EDS detector, to explore the corresponding cracking mechanism. The results show that the cracks start on the inner surface of the flange and extend outside. The microstructure in the welding heat affected zone (HAZ) is coarse and carbides are occurring at the grain boundaries, which reduces the strength. The precipitation of carbides at grain boundaries also reduced the Cr content in the crystal, resulting in a decrease in the corrosion resistance of the passivation film on 304 SS. The HAZ showed lower elongation compared to the 304 SS substrate and the fused zone. Under the combined action of stress and corrosive media, the HAZ undergoes stress corrosion cracking. [ABSTRACT FROM AUTHOR]

This paper presents a new method for forming flanges in hollow parts. The process consists of an extrusion with two dies that move in an opposite direction to that of the punches. This particular kinematics of the tools makes it possible to form two flanges simultaneously in a single tool pass. The proposed method was investigated using a tube made of steel 42CrMo4. It was assumed that the extrusion would be conducted as a cold forming process at ambient temperature. Different diameters and heights of the impression made in the top and bottom dies were used. It was demonstrated that the main failure mode of the proposed technique was an unintended increase in the inside the diameter of the workpiece in the flange zone. The results showed that the above parameters had a key impact on the achievable maximum flange diameters and heights. [ABSTRACT FROM AUTHOR]

Copyright of Metal Working (1674-165X) is the property of Metal Working Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The object of this study is the process of directing the bogies of model 18-100 freight cars along a rail track, in particular, along curved sections of the track. The task to be solved was to determine the influence of wheelset arrangement on the level of steering forces in the flange contacts. A calculation diagram and a mathematical model of fitting the bogie into the curved section of the track have been built. The bogie loading scheme by external forces, including lateral rocking forces acting on the car in a curve, has been refined. In this case, the method of pseudo-statics of the mechanical system, which is a system of nonlinear algebraic equations, was applied. The calculation module Given-Find in the Mathcad software package (USA) was used to solve the mathematical model. It was established that the misalignment of wheelsets in the frames of model 18-100 bogies was of an accumulative nature. At the maximum operating angles of misalignment of wheelsets, the lateral steering forces in the flange contacts increase by 40–60 % compared to the rated setting. These angles can be up to 0.015 rad (0.85 degrees). The field of practical application of the results is railroad transportation, in particular, the system of maintenance and repair of freight cars on bogies of the 18-100 model. At the same time, the condition for the practical application of the research results is the expediency of introducing into the maintenance system the technological operation of controlling the deviation of wheelset arrangement in the bogie relative to the rated one. The current study will contribute to the construction of a measuring system for monitoring the deviation of wheelset arrangement in the bogie relative to the rated one. This proves the expediency of introducing into the trolley maintenance system the technological operation of controlling the deviation of wheelsets and designing a device for monitoring this parameter. [ABSTRACT FROM AUTHOR]

Heat exchangers, as essential devices for facilitating heat transfer, have found a variety applications in various industries. However, the occurrence of corrosion-related failures in real-world scenarios remains a prevalent problem that can lead to catastrophic incidents. This paper investigates the problem of corrosion perforation on the outlet flange of a heat exchanger in a sour steam stripper from a petrochemical company. Failure analysis was performed using physical testing and chemical analysis, metallographic examination, microscopic observation, and energy spectrum analysis. Intergranular corrosion experiments and flow calculations were performed to verify the analysis. The results indicate that the main cause of the flange corrosion perforation was the formation of a highly concentrated NH4HS aqueous solution during the cooling process of the NH3, H2S, and water vapor in the fluid passing through the heat exchanger, and the velocity was too high, which triggered alkali-sour water washout corrosion. To prevent the recurrence of similar corrosion perforations, recommendations for material and process optimization are proposed to effectively reduce the safety production risks in refinery units and provide valuable information for the safe long-term operation of a sour steam stripper. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PurposeTo present the outcomes of a new technique for intrascleral fixation of a flanged three-piece foldable intraocular lens (IOL) without a conjunctival incision.Materials and methodsWe retrospectively reviewed a consecutive series of 12 eyes of 12 patients who underwent scleral IOL fixation using this technique.ResultsThe follow-up period ranged 3–12 months. There was a significant improvement in best-corrected visual acuity, from 0.8 (1.6) logarithm of the minimum angle of resolution (logMAR) preoperatively to 0.45 (0.8) logMAR at the final postoperative follow-up (p = 0.012). Notable complications included one case of pupillary IOL capture and increased intraocular pressure.ConclusionOur novel technique is a viable solution for managing secondary IOL fixation, enabling the use of a wider variety of IOLs and simplifying the reposition process for dislocated three-piece IOLs. This approach has the potential to lower complication rates and enhance patients’ recovery.

To enhance the uplift capacity and facilitate the installation of multi-row perfobond connectors at shallow burial depths, this study puts forward a novel notched T-perfobond connector. The design incorporates an integrated flange at the bottom of the connector and a notch at the edge of the hole. Through pull-out model tests on four notched T-perfobond connectors, this research investigates their failure mechanisms and pull-out capacities. Utilizing the explicit dynamics method in ABAQUS, a finite-element model of the pull-out resistance test for notched T-perfobond connectors is established and verified against experimental data. Furthermore, a detailed parametric analysis involving 54 models is conducted, examining crucial parameters such as rib dimensions, hole geometry, flange size, notch width, bar diameter, and material properties. Based on the combined experimental and numerical results, this paper assesses the suitability of current formulas for calculating the pull-out capacity of perfobond connectors and proposes a refined calculation method specifically for notched T-perfobond connectors. All the findings reported in this paper can serve as a reference in the design and construction of composite structures.

The flange joint is an important connection in steel tube structures. In this paper, 11 groups of flange joint tests were conducted to investigate the influences of tube diameter, flange plate thickness, the distance from the bolt to the tube centroid, bolt numbers and material strength on the mechanical behavior. One of two failure modes in tests is that the excessive plastic deformation on the flange plate makes the flange plate lose the bearing capacity; the other is that the steel tube yield makes the joints fail. The results show that the calculating method for flange joint in Chinese design code is so safe that amplifying the calculating results of the code by 1.2 times would be closer to the bearing capacity of specimens. For a flange joint with different tube diameters, thickening the flange plate of thinner tube or thinning the flange plate of another tube are effective to ensure the deformations on both sides of the flange plates are equivalent. The ratio of the bearing capacity of the steel tube to that of flange plate should be greater than 1.7. And the thickness of the flange plate should be thicker than 14mm to reduce the deformation caused by cutting, drilling and welding during manufacturing.

This paper presents a new method for forming flanges in hollow parts. The process consists of an extrusion with two dies that move in an opposite direction to that of the punches. This particular kinematics of the tools makes it possible to form two flanges simultaneously in a single tool pass. The proposed method was investigated using a tube made of steel 42CrMo4. It was assumed that the extrusion would be conducted as a cold forming process at ambient temperature. Different diameters and heights of the impression made in the top and bottom dies were used. It was demonstrated that the main failure mode of the proposed technique was an unintended increase in the inside the diameter of the workpiece in the flange zone. The results showed that the above parameters had a key impact on the achievable maximum flange diameters and heights.

This study aimed to determine the re-revision rate in a cohort of patients who underwent revision total elbow arthroplasty (rTEA) for humeral loosening (HL) and identify factors contributing to re-revision. We hypothesized that proportional increases in the stem and flange lengths would stabilize the bone-implant interface significantly more than a disproportional increase in stem or flange length alone. Additionally, we hypothesized that the indication for the index arthroplasty would impact the need for repeated revision for HL. The secondary objective was to describe the functional outcomes, complications, and presence of radiographic loosening after rTEA. We retrospectively reviewed 181 rTEAs performed from 2000-2021. We included 40 rTEAs for HL performed on 40 elbows that either required a subsequent revision for HL (10 rTEAs) or had a minimum of 2 years of clinical or radiographic follow-up. One hundred thirty-one cases were excluded. Patients were grouped based on stem and flange length to determine the re-revision rate. Patients were divided based on re-revision status into the single-revision group and the re-revision group. The stem–to–flange length (S/F) ratio was calculated for each surgical procedure. The mean length of clinical and radiographic follow-up was 71 months (range, 18-221 months and 3-221 months, respectively). Rheumatoid arthritis was statistically significant in predicting re-revision total elbow arthroplasty for HL (P =.024). The overall re-revision rate for HL was 25% at an average of 4.2 years (range, 1-19 years) from the revision procedure. There was a significant increase in stem and flange lengths from the index procedure to revision, on average by 70 ± 47 mm (P <.001) and 28 ± 39 mm (P <.001), respectively. In the cases of re-revision (n = 10), 4 patients underwent an excisional procedure; in the remaining 6 cases, the size of the re-revision implant increased on average by 37 ± 40 mm for the stem and 73 ± 70 mm for the flange (P =.075 and P =.046, respectively). Furthermore, the average flange in these 6 cases was 7 times shorter than the average stem (S/F ratio, 6.7 ± 2.2). This ratio was significantly different from that in cases that were not re-revised (P =.03; S/F ratio, 4.2 ± 2). Mean range of moion was 16° (range, 0°-90°; standard deviation, 20°) extension to 119° (range, 0°-160°; standard deviation, 39°) flexion at final follow-up. Complications included ulnar neuropathy (38%), radial neuropathy (10%), infection (14%), ulnar loosening (14%), and fracture (14%). None of the elbows were considered radiographically loose at final follow-up. We show that a primary diagnosis of rheumatoid arthritis and a humeral stem with a relatively short flange relative to the stem length significantly contribute to re-revision of total elbow arthroplasty. The use of an implant where the flange can be extended beyond one-fourth of the stem length may increase implant longevity. [ABSTRACT FROM AUTHOR]

The performance of a three-layer metal gasket is affected by the contact width between the gasket surface and the rough flanges. In the simulation, proper flange roughness modeling will make it easier to predict the gasket performance later. The surface roughness modeling in the simulation will be compared with experimental measurements to determine how much contact occurs due to the rough flange surface. Experimental measurement of real contact width using a digital microscope and simulation using finite element software. The measurements between the simulation results of the real surface roughness model and the experimental results show that they are close to the same. So it can be said that our simulation model is close to the actual conditions.

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article discusses the issue of force behavior in a pre-tensioned bolt that is part of a symmetrical flange connection, loaded with an operating load parallel to the bolt axis. The first part describes the issue being dealt with in detail. The next part offers a brief description of the generally known theoretical approach to the solution, and also outlines the limitations of this approach. This part is followed by a theoretical analysis of working load behavior in the bolt of the analyzed device, using Finite Element Method (FEM). In this article, a comparison of several different approaches to the solution can be also found, followed by a description of the experiment preparation and its results. The obtained values also serve as a subject for reverse iterative analysis carried out using ANSYS software. The aim is to find a proper modification to the symmetric calculation model that would be consistent with the results of measurements from technical practice. All results achieved are described in the final part of the article. [ABSTRACT FROM AUTHOR]

We report a liquid-level sensor composed of a laser, prism, and photodiode array. The sensor does not require components, such as a sensor head, inside the container that stores liquid. The sensor detects the liquid level based on the difference between the intensities of laser light reflected at the liquid/glass and air/glass interfaces. As the detected liquid level shows a shift from the correct liquid level owing to surface tension and the broadening of the laser light, we correct the shift through calculations. The sensor can be attached to a flange-type glass viewport, providing compatibility with broad-ranging containers for industrial use. The sensor can accurately detect the liquid level with a maximum error of 0.3875 mm. We demonstrate the implementation and operation of the liquid-level sensor using a wireless system comprising a sensor head and wireless voltmeter. The reported sensor allows accurate measurement of the liquid level in a tank inside which foreign objects such as sensor heads cannot be installed. [ABSTRACT FROM AUTHOR]

• The material nonlinearity of CFRP and the joint nonlinearity on the flange are considered and introduced into modeling. • The joint model with non-uniform distribution parameters and dynamic boundaries effectively simulates the joint nonlinearity. • The proposed modeling method can accurately predict the nonlinear vibration response of the analyzed structure. • The effects of modal interaction and combined nonlinearity on the structure's vibration behavior is discussed. In this paper, a thorough investigation into the vibration response of bolted composite flanged-cylindrical shell structures, considering the material nonlinearity of carbon fiber-reinforced polymer composites (CFRP) and the joint nonlinearity of bolt connections, is presented. Firstly, a general semi-analytical modeling method for bolted composite flanged-cylindrical shell is developed based on the first-order shear deformation theory (FSDT) and the energy method. In this method, material nonlinearity is introduced by accounting for the frequency-strain dependency of material parameters. A joint model with non-uniform distribution parameters and dynamic boundaries is proposed to simulate the interface pressure distribution and nonlinear mechanical behavior of bolted joints. Then, for the general numerical model that incorporates both types of nonlinearities, the ability to accurately predict the nonlinear vibration behavior of a bolted composite flanged-cylindrical shell is demonstrated through experimental testing. Finally, an in-depth discussion is conducted on the influence of fiber layup patterns and bolt numbers on the nonlinear vibration response of the bolted composite flanged-cylindrical shells. The conducted analysis indicates that the proposed method can offer utility to designers, empowering them with the insights necessary for the dynamic optimization of such structures. [Display omitted] [ABSTRACT FROM AUTHOR]

• Perform a failure analysis of the traction transformer oil pump flange. • Use a combination of physical, chemical, and finite element analysis. • The flange failure is characterized by overload fracture. A flange fracture occurred during the installation of a traction transformer oil pump. The causes of the flange fracture were analyzed using physical, chemical, and finite element methods. The fracture surface shows expanded edges and a linear fracture source, indicating an overload fracture. No significant defects such as pinholes, looseness, or cracks were found in the internal structure, which contains elongated Si phases. The Si, Ti, and Zn content in the failure part does not meet standard specifications. The hardness of the failure part is HBW107.8, meeting standards, but the elongation at break is at the lower limit, suggesting higher material brittleness. Finite element analysis revealed a maximum tensile stress of 241.5 MPa on the flange, close to the yield strength, indicating a small safety margin. The flange fracture is related to high material brittleness and potential assembly anomalies. To prevent similar incidents, strict control of raw material quality, regular inspection of mechanical properties, and finite element analysis for structural optimization are necessary. [ABSTRACT FROM AUTHOR]

PurposeTo describe a new technique for repairing wide iridodialysis (>180°) with a double-armed flanged polypropylene suture.SettingPrivate practice, Wuhan, China.DesignCase report.MethodsAdjacent to the iridodialysis side, the sclera was punctured 2 mm exterior to the corneal limbus into the anterior chamber with a 30-G needle, then the root of the de-inserted iris was punctured. A 7-0 polypropylene thread was placed into the anterior chamber through a corneal incision on the opposite side and inserted into the needle. The needle was withdrawn, leaving one side of the suture out of the eye. Then, the sclera was punctured by a new needle 2 mm from the first puncture site and passed through the iris root 2 mm from the original iris puncture point. The other end of the thread was inserted into the needle and taken out of the eye. The suture was tightened to make the iris root adhere to the corneal limbus. Finally, the suture is was cut, and the ends were cauterized and left inside the sclera. This procedure can be repeated until the iridodialysis is solved.ResultsThe abovementioned technique was applied in four cases. At the end of the operations, the pupils of all patients were nearly round, with a diameter of about 3 mm. No patient suffered from intraoperative and postoperative complications.ConclusionsThe double-armed flanged polypropylene suture is a simple and safe operation method that can be applied to repair wide iridodialysis.

A new S600E sorbite stainless steel (SS), which performs outstanding mechanical properties, was introduced in a plate girder to enhance the resistant performance and durability. The resistance from the flange for S600E sorbite SS plate girders developing post-buckling capacity was investigated through numerical analyses, which included the material and geometrical nonlinearity. The value of distance between plastic hinges performed significant effects on resistance from flange. There was a certain distribution range of the flange plastic hinge. Hence, it was difficult to determine the value of distance between plastic hinges accurately based merely on the failure behavior. Considering the theoretical basis of EN 1993-1-4: 2006+A1, the new methods to obtain resistance from the flange and determine the value of distance between the plastic hinges were proposed to avoid the aforementioned error. The parametric study was conducted to investigate the effect of key parameters on the resistance from the flange. To take the above effect into account, a correction factor was proposed for the design equation in EN 1993-1-4: 2006+A1 to predict the distance between flange plastic hinges accurately. The comparison was conducted to validate the accuracy of the proposed equations. The results indicated that the new modified equation could be used to predict the resistance from the flange of the S600E sorbite SS plate girder more accurately. [ABSTRACT FROM AUTHOR]

In this article, two wideband choke flanges (Flange 1 and Flange 2) are designed to reduce the passive intermodulation (PIM) level of the orthmode transducer (OMT). Since flange connections are important sources of PIM, circular Flange 1 introduces a choke groove and achieves a power suppression level of 41.95 dB. To meet the requirement of miniaturization and lightweight, Flange 2 with rectangular structure and rectangular choke groove is proposed for reducing height waveguide. Compared with conventional circular choke flange for reduced height waveguide, it has a smaller cross area and better power suppression level (39.92 dB). To evaluate the PIM performance of the proposed OMT with two flanges, temperature circulation test is executed. It is proved that the third-order PIM level is about −135 dBm from measurement results. Therefore, the proposed flanges can be utilized in large-scale multibeam array for low PIM satellite communication applications. [ABSTRACT FROM AUTHOR]

• Two composite gaskets with graphite insertion proven for He cooling circuits. • The graphite-layer of 1.60 mm shows significantly lower He and N 2 leak rates. • No deterioration of the sealing properties during the long-term tests up to 400 h. • Temperature increase of leak rates but the gasket still keeps excellent tightness. The article focuses on the problem of helium leakage from high-pressure reactor circuits through flange joints. The use of a laboratory apparatus developed to identify the most suitable gasket is demonstrated on two sample gaskets selected on the basis of preliminary measurements. The apparatus works on the principle of the sample placement in a standardized flange located in a space isolated from the environment. At laboratory temperature, the pressure inside the simulated pipe can be maintained at a maximum of 35 MPa; at the maximum operating temperature of 450 °C, the maximum pressure possible is 7 MPa. Gas analysis outside and inside the flange joint is provided by two gas chromatographs, one of which is equipped with a thermal-conductivity detector (TCD) and the other with a pulsed discharge helium ionization detector (PDHID). In particular, the study discusses the effect of elevated temperature on the sealing properties of the samples, the influence of graphite-layer thickness on gas diffusion and effusion, and finding the optimal leak-measurement time based on the standard deviation. The best sample tested was a kammprofile gasket with a steel insertion and two graphite layers of the thickness of 1.60 mm. At the temperature of 300 °C and the pressure difference of 5.7 MPa, this sample achieved a specific helium-leak rate of 1.5 10−5 mg s−1 m−1. In this case, the observed rate of nitrogen diffusion against the direction of the pressure gradient was almost three orders of magnitude lower, namely 8.9 10−8 mg s−1 m−1. Considering the detection limits of the analyzers used, the best experimental time for gaskets with such low gas-transport values has been determined as 200 h. [ABSTRACT FROM AUTHOR]

Copyright of Special Oil & Gas Reservoirs is the property of Special Oil & Gas Reservoirs Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sealing and relaxation characteristics of fluoroplast-4 gaskets are studied. It is established that, at the same specific pressure, the use of wider gaskets can increase sealing of the working pressure by about 25%. The influence of the stress level and time on the value of the relaxation modulus is also studied. A safety coefficient is proposed that takes the relaxation of specific pressures into account. Results of a control experiment conducted to assess the adequacy of the relaxation model are presented along with practical recommendations. [ABSTRACT FROM AUTHOR]

Objective: This study aimed at evaluating the supporting and non-supporting loop colostomy techniques in dogs. Materials and Methods: In this study, 12 adult healthy mongrel dogs were used to carry out a short-term (21 days) temporary flank loop colostomy. The dogs were divided into two groups (n = 6). In the first group (Con group), conventional stoma fixation was operated without loop support. In the second group [subcutaneous silicone drain (SSD) group], an SSD was used as a supporting bridge. The stoma was fixed by a modified, interrupted seromuscular vertical mattress suture pattern. Both peristomal and stomal complications were recorded. Results: Results showed that a total of seven dogs (58%) suffered complications. There was a sig¬nificant tendency toward less peristomal (p = 0.012) and stomal complications (p = 0.001) in the SSD group. The intensity of pain was significantly (p < 0.05) different between the two groups in the first week post surgery. Comfort with stoma care was significantly (p = 0.015) better in the SSD group, experiencing the best results. Conclusion: It is concluded that an appropriate stoma location, using a soft supporting bridge, stoma fixation using modified interrupted neuromuscular vertical mattress sutures, and proper appliance fixation by adhesive tapes and a tight T-shirt may overcome the complications of short-term loop colostomy in dogs and introduce a satisfaction for stoma care. [J Adv Vet Anim Res 2020; 7(4.000): 685-691]

Applied loads in bolted geometries of safety critical components can vary with time and operating conditions. Structural integrity and remaining life assessments of such components in aging industrial plants must consider the resultant changes in damage accumulation rates and acceptable defect sizes. Two case studies are presented that demonstrate the effect of bolt pre-load on creep and fatigue lives as well as on the acceptability assessments of defects. In the first case the sensitivity of creep damage accumulation and crack propagation rates to bolt pre-load in high temperature flanged connections are considered. Predicted results were found to compare well with actual damage quantified on a high pressure turbine loop pipe flange connection. It was shown that decreased pre-loads, in this case, leads to an increase the allowable safe defect size during assembly at room temperature. In contrast to this the second case study of corrosion fatigue cracking in a boiler water circulating pump illustrates that an increase in bolt pre-load leads to an increase in fatigue initiation life, a decrease in fatigue crack propagation rate and an increase in the acceptable defect size. Strain gauge measurements of bolt and casing strain, which correlated well with finite element calculations, indicated the necessity for close control of bolt pre-load during assembly to ensure specified levels are attained. In both cases metallurgical analysis and structural integrity assessments of cracked and excavated geometries were conducted which enabled limited continued operation of the components after which repairs and/or replacements will be implemented. [ABSTRACT FROM AUTHOR]

With 205 000 people in the UK with a stoma, it is likely that community nurses will need to consider which stoma products are most appropriate to use with this group of patients. This article explores the three output stomas, what stoma appliances are most commonly used for each type of stoma and why. Understanding how often stoma appliances should be changed empowers the community nurse in their decision-making process to ascertain whether changes to current care are needed. There is also information available about some of the more commonly used stoma accessories and when these may be necessary. With so many stoma-related products available, it can be difficult to know what to use and when; therefore, this article seeks to offer data to aid stoma care in the community. [ABSTRACT FROM AUTHOR]

Avner Hostovsky,1,2 Mark Mandelcorn,1,2 Efrem D Mandelcorn1,2 1Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada; 2Department of Ophthalmology, Toronto Western Hospital, The University Health Network, Toronto, Ontario, CanadaCorrespondence: Avner HostovskyDepartment of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, CanadaEmail av_ho@yahoo.comPurpose: To describe and evaluate the clinical outcomes of the Flanged Prolene Suture intraocular lens fixation (PIF) technique and compare it to anterior chamber IOL (ACIOL) implantation.Design: A retrospective comparative review.Methods: A retrospective comparative review of consecutive patients undergoing secondary IOL implantation was performed. A comparison between patients that had ACIOL and PIF technique was conducted. The main outcome measures were changes in best-corrected visual acuity (VA), IOL position and complications.Results: In the study period, fourteen eyes had ACIOL implantation and ten eyes had PIF surgery. VA acuity for both groups combined improved from 1.27 ± 0.65 logMAR preoperatively to 0.84 ± 0.65 logMAR (P< 0.0001). Seventeen patients had VA measurements in the year before the IOL dislocation. In those seventeen patients, VA changed from a baseline of 0.90 ± 0.68 to 0.97 ± 0.61 logMAR in the PIF group (p=0.334) and from 0.54 ± 0.27 to 0.85 ± 0.65 logMAR in the ACIOL group (p=0.145). No intraoperative or early postoperative complications were documented in either group. Two (20%) patients in the PIF group developed CME and one patient developed corneal edema. In the ACIOL group, one patient developed significant CME and two patients developed visual significant corneal edema.Conclusion: The PIF technique seems to offer a simple, fast and safe way to fixate an IOL posteriorly. In our experience, the learning curve of the technique is short with a low complication rate and good visual outcomes.Keywords: four-point, flange, IOL fixation

Production of prefabricated pipe spools for the needs of the oil and gas industry requires precise determination of their shape and dimensions. The crucial moment of production is to measure the spool being built, compare it with the design and define the geometry corrections that should be applied at the construction stage. At present, the comparison of spools is usually done in a manual manner in a CAD program or other software dedicated for this purpose and is implemented by combining variously defined translations and rotations. This approach is time-consuming and the results strongly depend on the survey engineer’s experience. In this article, a method of comparing the shape of two spools, based on isometric transformation and robust estimation, has been proposed. This method can be used to automate the comparison process. In standard approach, applied by both design engineers and assemblers, spools are described by a set of coordinates and, in the case of flanges, by sets of appropriately defined angular values. A method of flange description suitable for use in the isometric transformation process has been proposed, and potential problems that may appear at the implementation stage of the algorithm have been discussed. The proposed method makes it possible to determine the elements of a spool that do not fit into the design project in a way that allows minimizing the number of corrections at the construction stage.

This article discusses the issue of force behavior in a pre-tensioned bolt that is part of a symmetrical flange connection, loaded with an operating load parallel to the bolt axis. The first part describes the issue being dealt with in detail. The next part offers a brief description of the generally known theoretical approach to the solution, and also outlines the limitations of this approach. This part is followed by a theoretical analysis of working load behavior in the bolt of the analyzed device, using Finite Element Method (FEM). In this article, a comparison of several different approaches to the solution can be also found, followed by a description of the experiment preparation and its results. The obtained values also serve as a subject for reverse iterative analysis carried out using ANSYS software. The aim is to find a proper modification to the symmetric calculation model that would be consistent with the results of measurements from technical practice. All results achieved are described in the final part of the article.