Polyethylene Pipe Research Articles

DEVELOPMENT OF FRICTION STIR WELDING TOOL FOR HIGH-DENSITY POLY-ETHYLENE (HDPE)–CASE STUDY: FIBERGLASS COMPOSITE MATERIAL

This study aims to develop an effective Friction Stir Welding (FSW) method for composite material of High-Density Poly-Ethylene (HDPE) Pipes. The development of welding tool, there was the addition of an external heating source on the shoulder and probe/pin to overcome the problem of lack of heat resulting from friction between the tool and the material to be welded. The case study was conducted to join the short fiberglass-HDPE composite with a type of ratio of 30% by weight of short fibre and 70% by weight of HDPE, which optimizing parameters such as rotating speed, welding speed, and preheating temperature. The FSW joining process for short fiberglass-HDPE composite sheets was carried out using a Fanuc Series 21i-M CNC milling machine as the driving tool with rotational speed (ω) varied in 3 conditions, namely 600 rpm, 800 rpm and 1000 rpm, and welding speed (v) or feeding at 5 mm/minutes and 10 mm/minutes. The temperature was controlled according to the liquid point of High-Density Poly-Ethylene, which was 130oC, and raised to 150oC and 170oC. The 12 pieces of thermocouple were used along the track on the material and jig plates at the top, middle and bottom. Then, the results of joining the sheets were made in the form of specimens with sizes according to ASTM 3039. The tensile tests of the specimens were carried out at a rate of 0.01 mm/s. The results showed the highest tensile strength was an average value of 24.52 MPa at a rotational speed of 800 rpm, the feeding of 5 mm/min and the temperature of 130oC. The lowest tensile strength was an average value of 17.54 MPa at a temperature of 170°C with a speed of 600 rpm.

GIS-BASED REAL-TIME GAS LEAK DETECTION SYSTEM AT BASKENT NATURAL GAS DISTRIBUTION COMPANY

Abstract. Natural gas has been used for heating and production purposes in Turkey since 1987, and every passing year, the natural gas pipeline network continues to expand with investments. The distribution of natural gas within urban areas is achieved through a complex network structure formed by the joining of Polyethylene (PE) and Steel (ST) pipes using various connection elements. This complex structure is susceptible to deformation over time due to various reasons such as corrosion in steel lines, manufacturing errors in connection elements in PE lines, and other factors. As a result, natural gas leaks occasionally occur in these pipelines. The leakage control process in natural gas pipelines is carried out using specially designed equipment and vehicles equipped for this purpose. However, while these systems may be sufficient for collecting the necessary data for leak detection, the complex structure of the distribution network and the necessary data for leak detection, the complex structure of the distribution network and the necessity of performing this process with multiple teams bring about many challenges in terms of tracking, management, and reliability of the operation. At this point, the advancement of GIS (Geographic Information System), mobile, and communication technologies has made it possible to overcome these challenges. In this study, a real-time GIS-supported leak detection system developed using these technologies for Başkent Natural Gas Distrubition Inc. (Başkentgaz), which provides natural gas distribution services in Ankara, has been described. The study discusses the benefits brought by this system to the natural gas leak detection process.

Stress-Strain State of a Welded Joint in Welding a Saddle Branch to a Polyethylene Pipe under Low Temperatures

Purpose of research. The aim of the study is a comparative analysis of the stress-strain states of welded joints during welding of saddle branches to existing gas pipelines under normal conditions using standard technology and low temperatures using the proposed technology.Methods. To achieve the goal, a numerical implementation of the mathematical model of the thermoelastic state by the finite element method in the Python programming environment using the Fenics computing package was performed. The computational grid was built using the GMSH program. Visualization of the obtained results was implemented using the Paraview package.Results. On the basis of computational experiments of welding a saddle branch to an existing gas pipeline at permissible and low ambient temperatures, the dynamics of the temperature fields, stresses and strains in the heataffected zone are almost identical.Conclusion. The calculation results showed that when welding saddle branches to polyethylene pipes of existing gas pipelines at low temperatures using the proposed technology, the main physical and mechanical processes will proceed as in welding under normal conditions and provide the necessary strength.

Fatigue crack growth and slow crack growth of HDPE pipes under internal pressure and flat plate compression

High-Density Polyethylene (HDPE) pipes are widely used in city gas and water systems as buried pipelines for their excellent performance. However, in addition to the internal pressure, it also suffers loads from traffic vehicles, foundation settlements, and illegal buildings. In this paper, fatigue crack propagation of HDPE pipes with a longitudinal external crack was experimentally studied under different load ratios in two cases. Pulsatile internal pressure was implemented in the first case. In the other one, pulsatile flat plate compression and constant internal pressure were applied. The crack mouth opening displacements were recorded by the digital image correction technique. The crack depth was obtained with compliance calibration. It shows that the fatigue crack growth rate decreases as the load ratio increases. In both cases, the slow crack growth kinetics were gained by extrapolating the load ratio to 1.0, representing constant internal pressure or flat plate compression.

Hygienic Analysis Of Microclimate Indicators At Polymer Production Enterprises

During the study, unfavorable microclimate indicators were assessed at the Jizzakh enterprise for the production of polymer products. The microclimate indicators at the enterprise for the hot period of the year (July, August) differed somewhat from comfortable indicators. The air temperature in the workshop for the production of consumer goods was above the maximum permissible dose from 0,80C to 6,90C. In the workshop for the production of polyethylene products films from 3,60C to 5,50C, in the workshop for the production of polyethylene pipes - from 3,80C to 4,60C, and at workplaces in the workshop for the production of polyethylene components from 3,80C to 4,60C

Laboratory Investigation of the Structural Performance of a Large-Diameter Steel-Reinforced Polyethylene Pipe

Laboratory Investigation of the Structural Performance of a Large-Diameter Steel-Reinforced Polyethylene Pipe

Study on the impact of soil environment organic substances on the ageing of urban PE gas pipes in service

PurposeThe service environment of urban polyethylene (PE) pipes has a crucial influence on their long-term safety and performance. Based on the application and structural performance analysis of PE pipe failure cases, this study aims to investigate the impact of organic substances in the soil on the aging behavior of PE pipes by designing organic solutions with different concentrations, which are based on the composition of organic substances in the soil environment, and periodic immersion tests.Design/methodology/approachSoil samples in the vicinity of the failed pipes were analyzed by gas chromatography-mass spectrometry, sensitive organic substances were screened and soaking solutions of different concentrations were designed. After the soaking test, the PE pipe samples were analyzed using differential scanning calorimetry, Fourier-transform infrared spectroscopy and other testing methods.FindingsThe performance difference between the outer surface and the middle of the cross section of PE pipes highlights the influence of the soil service environment on their aging. Different organic solutions can have varying impacts on the aging behavior of PE pipes when immersed. For instance, when exposed to amine organic solutions, PE pipes may have an increased weight and decreased material yield strength, although there is no reduction in their thermal or oxygen stability. On the contrary, when subjected to ether organic solutions, the surface of PE pipe specimens may be affected, leading to a reduction in material fracture elongation and a decrease in their thermal and oxygen stability. Furthermore, immersion in either amine or ether organic solutions may result in the production of hydroxyl and other aging groups on the surface of the material.Originality/valueUnderstanding the potential impact of organic substances in the soil environment on the aging of PE pipe ensures the long-term performance and safety of urban PE pipe. This research approach will provide valuable insights into improving the durability and reliability of urban PE pipes in soil environments.

Optimization of double layered horizontal directional drilled ground heat exchangers by water injection into the borehole

Ground Heat Exchangers (GHEs) drilled using Horizontal Directional Drilling (HDD) technology have been proven to be a cost-efficient way of installing ground source heat pump systems (GSHP). They can also be installed in places where conventional horizontal ground heat exchanger (HGHE) would not be possible e.g., due to lack of land.In this research, a double layered horizontal borehole was installed as a GHE in Saga City, Japan. The two holes had a diameter of 114.3 mm and a length of 59 m and 56 m, respectively, while reaching depths of 5 m and 9.5 m. A polyethylene pipe with an outer diameter of 60 mm was inserted as a borehole heat exchanger (BHE). In March 2022, a two days thermal response test (TRT) showed the influence of rainfall on the system. A numerical model developed in FEFLOW based on the GHE dimension and the region's geology was validated using the measured temperatures of the heat medium at the return point and outlet of the GHE during the TRT. The validated model was then used to carry out sensitivity analysis examining different conditions of water injection into the borehole. The result of the sensitivity analysis showed that water injection into the borehole can improve the performance of the system and reduce the temperature change of the heat medium. Varying the injection rate can improve performance to a certain degree and the injection point has a strong influence on the performance. The injection temperature was also found to play a role in the performance, but even high temperatures in the case of heating showed significant improvement. Lastly, the influence of permeability was investigated and showed that impermeable layers are more favorable for injection compared to permeable layers.

Grand canonical Monte Carlo and molecular dynamics investigation of hydrogen solubility and diffusivity in nonmetallic polyvinyl chloride, polyethylene and polyvinylidene fluoride pipes materials

To choose appropriate nonmetallic pipe materials for reducing hydrogen permeation, the hydrogen permeability in polyvinyl chloride, polyethylene, and polyvinylidene fluoride are studied and compared by molecular dynamics simulations. The findings demonstrate the solubility coefficient of hydrogen in polyvinyl chloride rises as the temperature decreases. However, in polyethylene and polyvinylidene fluoride, the trend is reversed. With the decrease of temperature, the diffusion and permeability coefficients decrease. The diffusion of hydrogen molecules follows the jumping mechanism. Among the materials studied, polyvinylidene fluoride is the most suitable material for hydrogen pipes due to its superior resistance to hydrogen permeation.

Design and optimization of ground‐coupled refrigeration heat exchanger in Dubai: Numerical approach

AbstractGround‐coupled heat exchangers (GCHE) have received significant attention over several decades as a result of increasing the world's energy demand and the need for reducing fossil fuels consumption. Prior studies have demonstrated the effectiveness of utilizing GCHE with refrigeration and heating systems. However, optimizing the performance of GCHE coupled with chillers for heat rejection, especially in extreme hot‐humid climates (where cooling towers are not very effective) is lacking in the literature. In this work, a ground borehole fitted with a coaxial‐tubes heat exchanger (BHE) is numerically simulated. Based on a wide range of data collected for the soil of Dubai, its real in situ thermophysical properties are characterized. The soil's upper layer thickness is relatively small and dry that operates in conduction mode, while the lower one is water‐saturated that works in coupled conduction‐advection mode. The study aims at optimizing the parameters advancing heat rejection into ground considering the actual properties of the soil of Dubai. The results indicate that the more feasible high‐density polyethylene pipes can perform as good as the steel ones. Also, a great finding based on the presented novel design is that insulating the inner pipe can increase the temperature duty by 55%. The proposed design of BHE is relatively inexpensive, more feasible and efficient, which is achieved for the first time based on a deep analysis of Dubai climate and soil. This makes the technology ready to be implemented for industrial applications in Dubai and other regions having a similar climate and soil nature.

Tracing the origins of plastics in biosolids: The role of sewerage pipe materials and trade waste

Plastics are ubiquitous in virtually every environment on earth. While the specific sources of plastics entering wastewater are not well known, growing evidence suggests sewage sludge (biosolids) can be a sink for plastics. One potential source could be the sewerage pipe materials used to transport sewage between premises and wastewater treatment plants (WWTPs). To evaluate the significance of sewerage piping as a source of biosolids plastics concentrations, we compared the proportion of the total network (by length and surface area) of polyethylene (PE), polyvinylchloride (PVC), and polypropylene (PP) pipes from 10 WWTPs against their biosolids mass concentrations (mg plastic/g biosolid). Among the 10 catchments, the percentage of the network consisting of PP piping ranged from 0 to 1 %, with 0.8–21 % for PE, and 8–73 % for PVC. Biosolids plastics concentrations ranged from 0.09 to 8.62 mg/g (mg plastic/g biosolid) for PP and PE, respectively. For all three plastics, there was no significant Pearson correlation (r < 0.4) between the biosolids concentration (dry weight mg/g) and the proportion of the network material of the sewerage piping as plastic (either length or surface area). A comparison of trade waste entering a subset of 6 WWTP showed the highest biosolid principal components analysis (PCA) associations between loads of plastics (g/day) and automotive wash bays, general manufacturing, hospitals, laboratories, food manufacturing, laundry and dry cleaning, and cooling towers. A stepwise regression analysis indicated pipe length and surface area, as well as automotive wash bays and food manufacturing may be significant. While our data gave mixed results on the attribution of the sources of plastics entering WWTPs, it suggests that sewerage infrastructure and trade waste may play some role. Future studies should investigate the leachability of sewerage infrastructure and contributions from specific trade waste categories to determine their significance in plastics entering WWTPs.

Technical and economic calculation of a high (medium) pressure dead-end gas network

The article is devoted to the analysis of situations that arose as a result of the explosion of the Nord Stream gas pipelines and Europe’s refusal of Russian gas. Russia is forced to redistribute gas flows. There was a need to increase gas supplies to China. Moreover, the corresponding gas pipelines have already been built. But most importantly, the prospect of providing gas to Russian consumers arose. A strange situation has arisen when Ukraine is 100% supplied with natural gas, and Russia supplies its consumers with 70%. At the same time, Russia has enormous reserves of natural gas. To supply consumers with economical and safe fuel, it is necessary to design the gas distribution system in such a way that, regardless of the mode of gas consumption, a stable pressure is maintained in front of gas appliances. This requirement can be met by using a pressure regulator for each consumer. The designed system is characterized by reduced capital costs, as there is a transition from a ring to a dead-end circuit. But most importantly, the laying of low-pressure gas pipelines is excluded from the gas distribution system. When hydraulically calculating a dead-end gas network of medium and high pressure, the differences between successive sections are redistributed in such a way that the total cost of capital costs, or material characteristics, is significantly reduced. Currently, polyethylene pipes are widely used in the construction of gas networks, which have significant advantages over steel ones, since they do not corrode.

Increasing cotton fiber quality in the process of cotton transportation in polyethylene pipes in cotton processing plants

In this article, cotton quality scrapers were identified by applying the erucamide product to cotton processing plants in place of existing steel pipes in cotton refineries for the first time in polyethylene. Technologies in cotton ginning enterprises were studied. For the purpose of producing quality cotton fibers and seeds, their advantages and disadvantages were considered and the degree of damage was studied. The article shows the advantage of the production process of rational use of the pneumotransport system.

The effect of age and wear on the mechanical performance of HDPE 80 polyethylene pipes

In this work, we studied the influence of accelerated aging in an aggressive environment of high-density polyethylene (HDPE 80) used for pipeline applications to distribute gas. Accelerated aging by ultraviolet irradiation of the wavelength lamps (λ = 365nm) for 240 hours at a temperature of 35°C exposed samples to solar radiation on the sand in southern Algeria for 12 months. The samples were subjected to weathering at -10 °C and 25°C for four different durations. To assess the weight loss capacity of semi-crystalline polymer behavior (HDPE 80) Under accelerated aging conditions, aging is carried out mainly according to three referenced methods: ISO 105 B02/B04, DIN 75202, and SAE J 1885. The Taguchi method and regression analysis were used. Several experiments were conducted on a vertical milling machine using a multi-factor L16 (4^1*2^3) orthogonal mixed matrix. An analysis of variance (ANOVA) was used to determine the effects of treatment: corrosion, weight loss, and loss of thickness. The parameters are influenced by the sandpaper's grain diameter, cutting speed, and compressive strength continuity over two hours, with each trial lasting 15 minutes. Using S/N ratios, optimal control factors were determined to minimize lost weight (P) and thickness loss (∆L) due to abrasion of HDPE polyethylene pipes 80. At A3, B2, C2, D2 (i.e. degradation mode = UV, rotation speed = 355 rpm, load = 9.3 N, abrasive paper = 10.3 degrees) and A3, B1, C2, D1 (i.e. degradation mode = UV, rotation speed = 180 rpm, load = 4.65 N, and abrasive paper = 18.3 degrees), ideal conditions for weight and thickness loss were observed.

Study of the coefficient of friction caused by the seed cotton flow action in pneumatic polyethylene pipes

Study of the coefficient of friction caused by the seed cotton flow action in pneumatic polyethylene pipes

Lifetime Prediction of Polyethylene Pipe Due to Aging Failure in Hydrogen-Blended Natural Gas Environment

Lifetime Prediction of Polyethylene Pipe Due to Aging Failure in Hydrogen-Blended Natural Gas Environment

Effect of operation duration on characteristics of polyethylene pipes

Effect of operation duration on characteristics of polyethylene pipes

Exciting and Detecting Higher-Order Guided Lamb Wave Modes in High-Density Polyethylene Structures Using Ultrasonic Methods.

High-density polyethylene (HDPE) pipes are becoming increasingly popular, being used in various fields, such as construction, marine, petroleum, water transfer, process water, methane gas collection, oil and gas gathering, gas distribution systems, mining, acid and wet gas lines, offshore oil and gas and in nuclear power plants. Higher-order guided Lamb wave (UGW) modes can be used to detect various defects in complex structures. We will apply this methodology to one of the types of plastic-the structure of high-density polyethylene (HDPE). However, the excitation of UGW modes faces numerous challenges, especially when there is a need to identify which mode is excited. It is essential to note that, in the higher frequency range, multiple different higher-order modes can usually be excited. This can make it difficult to determine which modes have actually been excited. The objective of this research was to successfully excite and receive various higher-order UGW modes in high-density polyethylene structures using both ultrasonic single-element transducers and a phased array. Theoretical calculations were performed using a variety of methods: semi-analytical finite element (SAFE) method, 2D spatial-temporal spectrum analysis and finite element modeling (FEM). The results obtained from both measurements and simulations clearly demonstrate the possibility of efficiently exciting and receiving different Lamb wave modes possessing different phase velocities.

A study on pipe failure analysis in water distribution systems using logistic regression

Abstract This study presents a pipe failure analysis that aims to identify key factors affecting pipe failure in a pilot study area (PSA). For this purpose, pipe failures that occurred in the PSA were recorded for 2 years. Recorded pipe failures were integrated into the existing geographical information systems of the PSA and then visualized. Then, the logistic regression model that calculates failure probability with unbalanced and small- and medium-sized data was performed to analyze pipe failures. Pipe material, age, diameter, burst pressure, and average water pressure are the factors used in the study. The developed model achieved a success rate of 70.1%, suggesting that it can predict a considerable portion of pipe failures with a relatively satisfactory performance. Findings show that the failure probability of pipes with an age greater than 20 years is 1.675 times higher than that of pipes with an age less than 20 years. Moreover, polyvinyl chloride pipes are 5.265 times and high-density polyethylene pipes are 9.027 times more likely to fail than ductile pipes. Further research should delve into the impacts of the number of service connections, pipe lengths, and traffic load on pipe failures.

Selection of Suitable Pipe Material for New Water Distribution Network Using Analytic Hierarchy Process – A Case Study of Athivilai Village of India

This study was made to design a new water distribution network for the Athivilai village of Tamilnadu, India. The associated problems of the village are improper water supply for growing water requirements during the summer season. The cost, service life, and material type play an important role when designing a new network. In this study, the suitable pipe material is chosen by using Analytical Hierarchy Process. The criteria selected for Analytic Hierarchy Process include Cost, Service life, Ease of maintenance, Corrosion, Leakage, and Internal pressure. The results show that the Ductile Iron pipe ranks top position followed by High Density Polyethylene, Polyvinyl Chloride, and Galvanized iron. After selecting the pipe material, the design of water distribution network is done in EPANET 2.0 software. The results show that the diameter of pipes ranges from 40 mm to 250 mm. Since the corrosion of smaller diameter Ductile Iron pipes are faster, the High Density Polyethylene pipe which acquires the second rank can be used for diameters smaller than 80 mm. For pipes with a diameter greater than 80 mm, Ductile Iron pipes are used. Furthermore, since a continuous system of supply is designed, the pressure rises above 60 m during non peak hours which indicates that the pipes are constantly subjected to internal pressure. Both the selected pipes can withstand high internal pressure which confirms the results obtained by the Analytic hierarchy process are suitable.