Structural design of pressure pipes

2001 ◽  
Vol 1 (3) ◽  
pp. 107-115
Author(s):  
I. Bjorklund
Keyword(s):  
Structural Design ◽  
High Strength ◽  
Strength Properties ◽  
Pipe Material ◽  
Working Pressure ◽  
Pressure Pipes ◽  
Flexible Pipes ◽  
Glass Fibre Reinforced ◽  
Design Calculations

There exist various methods for structural design of buried pressure pipes. However, it must be remembered that sophisticated design methods needs a significant supervision of the construction work to be reliable. The need for detailed calculations varies for different materials. Ductile iron (DCI) pipes have high strength properties and for most DCI pipe installations a design check against EN 545 is fully sufficient as regards the structural design. Glass fibre reinforced polyester (GRP) pipes have a limited strainability and are thus highly dependent on the quality of the installation work. It is recommendable to check that the combined strain of the load cases which the pipe shall be designed for does not exceed the allowable strain for the pipe material. Polyethylene (PE) and Polyvinylchloride (PVC) pipes are flexible pipes with a high strainability. The allowable working pressure for these pipes will normally be determined by the PN class and the operating temperature and the need for structural design calculations is limited. It is interesting to note that PE pipes which have the lowest strength properties of all of the above mentioned materials have the lowest failure rate. The latter shows that it is not just the tensile strength, but other factors such as strainability and corrosion resistance which affect the structural performance of buried pipelines.

Research on the Performance of Silt Sintered Insulating Brick and Key Molding Equipment

2014 ◽  
Vol 919-921 ◽  
pp. 2002-2006
Author(s):  
Hong Mei Liu ◽  
Yuan Bin Xu ◽  
Cheng Qun Wu ◽  
Ai Dong Zhu ◽  
Jun Qiu Zuo
Keyword(s):  
Thermal Insulation ◽  
Structural Design ◽  
Building Materials ◽  
High Strength ◽  
Sound Insulation ◽  
Critical Part ◽  
Research Status ◽  
Future Developments ◽  
Important Position

Silt sintered insulating brick with high strength, good thermal insulation and sound insulation characteristics. It occupies an important position in the new building materials industry. The main equipment for production of silt sintered insulating brick is the vacuum brick extruding machine, the forming mold is the most critical part in it. The performance largely determines the quality of the brick. The structural design and other aspects of the forming mold are analyzed, and then systematically summarize the design and production requirements of the forming mold. The research status of the forming mold on vacuum brick extruding machine at domestic and abroad is reviewed. The main problems of forming mold are analyzed and the corresponding solutions are given, as well as the future developments of forming mold.

Use of Polymer for Rehabilitation of Uneven Settlement in Concrete Roadbed Slabs of Tunnels

2015 ◽  
Vol 1129 ◽  
pp. 468-473
Author(s):  
Jing Liu ◽  
Xin Guo Zheng ◽  
Shu Ming Li ◽  
Zhi Zeng ◽  
De Jun Yang ◽  
...  
Keyword(s):  
High Strength ◽  
Strength Properties ◽  
Test Results ◽  
Polymer Injection ◽  
Railway Tracks ◽  
Low Viscosity ◽  
Compressive Strength Test ◽  
Injection Technology

In some tunnels of railway lines located in water-rich region, due to the long-term water leakage and erosion, the foundation of railway lines showed large uneven settlement deformation, so the above concrete roadbed slabs also experienced uneven settlement accordingly. The smoothness of railway tracks diminished, and the speed of passing trains had to be limited to ensure safety. To restore the smoothness of the tracks, a dedicated polymer injection technology for quick uplift rehabilitation of uneven settlement concrete roadbed slabs was studied on site just within the specified daily skylight time (about 3 hours every day) of the railway lines. A hydrophobic polymer with low-viscosity, quick-setting and high-strength properties was used for injecting, filling and uplifting the concrete slabs in water-rich foundations. The high-precision electronic levels were adopted to monitor rising height of the tracks in real time. After rehabilitation, the filling quality of polymer injection under roadbed slabs was examined using Φ50 mm core samples and the strength of hardened polymer was verified by compressive strength test. Results indicated that the polymer could uplift the concrete roadbed slabs effectively and restore the smoothness of railway tracks accurately even in the water-rich environment. The research can provide some valuable references for quick rehabilitation of uneven settlement concrete roadbed slabs in water-rich tunnels.

A novel predictive method for filler coflocculation with cellulose microfibrils

TAPPI Journal ◽  
2019 ◽  
Vol 18 (11) ◽  
pp. 653-664
Author(s):  
IGNACIO DE SAN PIO ◽  
KLAS G. JOHANSSON ◽  
PAUL KROCHAK
Keyword(s):  
Negative Impact ◽  
High Strength ◽  
Strength Properties ◽  
Cellulose Microfibrils ◽  
Paper Strength ◽  
Flow Loop ◽  
Cationic Starch ◽  
Reflectance Measurement ◽  
Drainage Rate ◽  
Complete Study

Different strategies aimed at reducing the negative impact of fillers on paper strength have been the objective of many studies during the past few decades. Some new strategies have even been patented or commercialized, yet a complete study on the behavior of the filler flocs and their effect on retention, drainage, and formation has not been found in literature. This type of research on fillers is often limited by difficulties in simulating high levels of shear at laboratory scale similar to those at mill scale. To address this challenge, a combination of techniques was used to compare preflocculation (i.e., filler is flocculated before addition to the pulp) with coflocculation strategies (i.e., filler is mixed with a binder and flocculated before addition to the pulp). The effect on filler and fiber flocs size was studied in a pilot flow loop using focal beam reflectance measurement (FBRM) and image analysis. Flocs obtained with cationic polyacrylamide (CPAM) and bentonite were shown to have similar shear resistance with both strategies, whereas cationic starch (CS) was clearly more advantageous when coflocculation strategy was used. The effect of flocculation strategy on drainage rate, STFI formation, ash retention, and standard strength properties was measured. Coflocculation of filler with CPAM plus bentonite or CS showed promising results and produced sheets with high strength but had a negative impact on wire dewatering, opening a door for further optimization.

PYROMET 600

Alloy Digest ◽  
1969 ◽  
Vol 18 (12) ◽  
Keyword(s):  
Base Alloy ◽  
High Strength ◽  
Heat Treating ◽  
Nuclear Industry ◽  
Temperature Performance ◽  
Resistance To Oxidation ◽  
Technology Corporation ◽  
Carpenter Technology Corporation ◽  
Nickel Base

Abstract Pyromet 600 is a corrosion-resisting nickel-base alloy, having a very desirable combination of high strength and workability, both hot and cold. It has high strength and resistance to oxidation at high temperatures. It is designed to meet the highest quality of the nuclear industry. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-149. Producer or source: Carpenter Technology Corporation.

Evaluation of quality of welded joints of high-strength railway rails of modern production taking into account the requirements of ukrainian and european standards

2020 ◽  
Vol 2020 (7) ◽  
pp. 2-10
Author(s):  
S.I. Kuchuk-Yatsenko ◽  
◽  
E.V. Antipin ◽  
O.V. Didkovskyi ◽  
V.I. Shvets ◽  
...  
Keyword(s):  
Welded Joints ◽  
High Strength ◽  
European Standards

Causes of gear pump fails and methods for their elimination

2020 ◽  
pp. 98-107
Author(s):  
Vitaliy A. Zuyevskiy ◽  
Daniil O. Klimyuk ◽  
Ivan A. Shemberev
Keyword(s):  
Adhesion Strength ◽  
Production Systems ◽  
Low Cost ◽  
High Strength ◽  
Strength Properties ◽  
Research Purpose ◽  
Working Fluid ◽  
Gear Pump ◽  
Repair Service ◽  
Recovery Method

Gear pumps are an important element of many production systems and their replacement in case of failure can be quite expensive, so it is important to have a modern and well-tuned technology for their recovery. There are many methods for restoring the pump's performance, depending on the reason that led to its failure. (Research purpose) The research purpose is in determining what causes most often lead to loss of pump performance, and developing a recovery method that provides the greatest post-repair service life of the pump and low cost of repair. (Materials and methods) Authors took into account that the applied coatings must have sufficient adhesion strength and resistance to mechanical, thermal and corrosion loads during operation. It was found that most often significant leaks of the working fluid, leading to failure, occur due to an increase in the gap between the inner surface of the housing and the gears due to active wear of the housing wells. Authors determined that the method of electric spark treatment of worn-out housing wells is best suited to perform the task (a large post-repair resource and low costs). (Results and discussion) It was found by laboratory studies of the adhesion strength of electric spark coatings with various electrodes that the best transfer of the material to the substrate is provided by bronze electrodes BrMKts3-1. It was noted that the coatings applied using the BrMKts3-1 electrode have high strength properties. (Conclusions) Research conducted in the center for collective use "Nano-Center" VIM confirmed the possibility of effective recovery of the gear pump by electric spark treatment.

scholarly journals Manufacturing and development of a bolted GFRP flange joint for oil and gas applications

2021 ◽  
pp. 095440542198951
Author(s):  
Muhsin Aljuboury ◽  
Md Jahir Rizvi ◽  
Stephen Grove ◽  
Richard Cullen
Keyword(s):  
Pressure Vessel ◽  
Oil And Gas ◽  
Polyester Resin ◽  
High Strength ◽  
Adhesively Bonded ◽  
Acceptable Quality ◽  
Composite Pipe ◽  
And Performance ◽  
Composite Pipes

The goal of this experimental study is to manufacture a bolted GFRP flange connection for composite pipes with high strength and performance. A mould was designed and manufactured, which ensures the quality of the composite materials and controls its surface grade. Based on the ASME Boiler and Pressure Vessel Code, Section X, this GFRP flange was fabricated using biaxial glass fibre braid and polyester resin in a vacuum infusion process. In addition, many experiments were carried out using another mould made of glass to solve process-related issues. Moreover, an investigation was conducted to compare the drilling of the GFRP flange using two types of tools; an Erbauer diamond tile drill bit and a Brad & Spur K10 drill. Six GFRP flanges were manufactured to reach the final product with acceptable quality and performance. The flange was adhesively bonded to a composite pipe after chamfering the end of the pipe. Another type of commercially-available composite flange was used to close the other end of the pipe. Finally, blind flanges were used to close both ends, making the pressure vessel that will be tested under the range of the bolt load and internal pressure.

scholarly journals Overview of HSS Steel Grades Development and Study of Reheating Condition Effects on Austenite Grain Size Changes

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1988
Author(s):  
Tibor Kvackaj ◽  
Jana Bidulská ◽  
Róbert Bidulský
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
High Strength Steel ◽  
Single Phase ◽  
Hsla Steel ◽  
High Strength ◽  
Strength Properties ◽  
Austenite Grain Size ◽  
Austenite Grain ◽  
Steel Grades

This review paper concerns the development of the chemical compositions and controlled processes of rolling and cooling steels to increase their mechanical properties and reduce weight and production costs. The paper analyzes the basic differences among high-strength steel (HSS), advanced high-strength steel (AHSS) and ultra-high-strength steel (UHSS) depending on differences in their final microstructural components, chemical composition, alloying elements and strengthening contributions to determine strength and mechanical properties. HSS is characterized by a final single-phase structure with reduced perlite content, while AHSS has a final structure of two-phase to multiphase. UHSS is characterized by a single-phase or multiphase structure. The yield strength of the steels have the following value intervals: HSS, 180–550 MPa; AHSS, 260–900 MPa; UHSS, 600–960 MPa. In addition to strength properties, the ductility of these steel grades is also an important parameter. AHSS steel has the best ductility, followed by HSS and UHSS. Within the HSS steel group, high-strength low-alloy (HSLA) steel represents a special subgroup characterized by the use of microalloying elements for special strength and plastic properties. An important parameter determining the strength properties of these steels is the grain-size diameter of the final structure, which depends on the processing conditions of the previous austenitic structure. The influence of reheating temperatures (TReh) and the holding time at the reheating temperature (tReh) of C–Mn–Nb–V HSLA steel was investigated in detail. Mathematical equations describing changes in the diameter of austenite grain size (dγ), depending on reheating temperature and holding time, were derived by the authors. The coordinates of the point where normal grain growth turned abnormal was determined. These coordinates for testing steel are the reheating conditions TReh = 1060 °C, tReh = 1800 s at the diameter of austenite grain size dγ = 100 μm.

scholarly journals Soil microbiomes mediate degradation of vinyl ester-based polymer composites

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Adam M. Breister ◽  
Muhammad A. Imam ◽  
Zhichao Zhou ◽  
Md Ariful Ahsan ◽  
Juan C. Noveron ◽  
...  
Keyword(s):  
Polymer Composites ◽  
Polymer Composite ◽  
Structural Integrity ◽  
Abiotic Factors ◽  
High Strength ◽  
Strength Properties ◽  
Naturally Occurring ◽  
Structural Applications ◽  
Acrylate Esters ◽  
Bacterial Groups

AbstractPolymer composites are attractive for structural applications in the built environment due to their lightweight and high strength properties but suffer from degradation due to environmental factors. While abiotic factors like temperature, moisture, and ultraviolet light are well studied, little is known about the impacts of naturally occurring microbial communities on their structural integrity. Here we apply complementary time-series multi-omics of biofilms growing on polymer composites and materials characterization to elucidate the processes driving their degradation. We measured a reduction in mechanical properties due to biologically driven molecular chain breakage of esters and reconstructed 121 microbial genomes to describe microbial diversity and pathways associated with polymer composite degradation. The polymer composite microbiome is dominated by four bacterial groups including the Candidate Phyla Radiation that possess pathways for breakdown of acrylate, esters, and bisphenol, abundant in composites. We provide a foundation for understanding interactions of next-generation structural materials with their natural environment that can predict their durability and drive future designs.

Sign in / Sign up

Export Citation Format

Share Document