Generation of filament winding patterns for elbows with various cross-sections

As a connecting component of tubes, the elbow is indispensable to pipe-fitting in composite products. Previous studies have addressed methods for generating winding paths based on parametric equations on the elbow. However, these methods are unsuitable for elbows whose surfaces are difficult to describe using mathematical expressions. In this study, a geometric method was proposed for generating winding patterns for various elbow types. With this method, the mandrel surface is first converted into uniform and high-quality quadrilateral elements; an algorithm is then provided for calculating the minimum winding angle for bridging-free. Next, an angle for non-bridging was defined as the design-winding angle to generate the uniform and slippage-free basic winding paths on the quadrilateral elements in non-geodesic directions. Finally, after a series of uniform points were calculated on the selected vertical edge according to the elbow type, the pattern paths were generated with the uniform points and basic paths. The proposed method is advantageously not limited to the elbow’s shape.

Instructor Training on Opioids and the Workplace, Prevention and Response in the Plumbing and Pipe-Fitting Industry: An Interview With Cheryl Ambrose

Workers in the plumbing and pipe-fitting industry experience a wide variety of physical and emotional pain related to job hazards and lifestyle issues. Pain treatment and stress can lead to prescription or illicit substance use. The United Association of Journeymen and Apprentices of the Plumbing and Pipe-Fitting Industry of the United States and Canada has taken on these issues by adapting training developed by the National Institute of Environmental Health Sciences, Opioids and the Workplace, Prevention and Response Training. Under the leadership of Cheryl Ambrose, Health, Safety, and Environmental Administrator, the United Association of Journeymen and Apprentices of the Plumbing and Pipe-Fitting Industry of the United States and Canada has added an instructor training course and is tailoring the National Institute of Environmental Health Sciences curriculum to industry and union needs.

Investigation of Compositional Effects of Virgin and Recycled HDPE on Mechanical Properties of Pipe

Nowadays, High-Density Polyethylene (HDPE) polymers are widely being used and its products are preferable than metals having the properties such as lightweight, ease of manufacture, stronger and tough. This makes HDPE polymers as the top choice by manufacturers. However, one of the drawbacks is that this polymer takes time to decay and affects the environment when this material is disposed as wastes. Almost all industries use only virgin imported materials to produce HDPE pipe and fittings, and this leads to increase in manufacturing cost and extraction of virgin material. The aim of this research is to overcome this problem by recycling process. This research work focuses on investigating the compositional effects of virgin and recycled HDPE on the mechanical properties of HDPE pipe fitting. The mixing of recycled with virgin (pure) HDPE were done at different weight percentages (0:100, 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 80:20, 90:10, and 100:0). In this work, 16.5 kg virgin HDPE were used, and 16.5 kg recycled HDPE pellets were prepared. Also, 11 (eleven) T-reducer pipe fitting samples were produced via injection moulding machine. Melt flow rate and ash content of the manufactured recycled materials were tested to determine the quality of the plastics. Tensile strength test was also conducted to investigate the mechanical property in order to determine the percentage which possess the optimum strength. From the experimental results, recycled contents up to 70 wt. % and virgin contents up to 30 wt. % by mass were found to meet the standard requirements. This optimum proportion will help AG Pipe fitting company to save a lot in dollars every year by using the scrap contents.

Problems of weld overlay of seating surfaces of pipe fitting and solutions

Introduction. A problem of providing the necessary functions of pipe fitting for blockage, control, distribution of the working medium flows under the most adverse operating conditions of oil and gas pipelines associated with abrasive particles, mechanical impurities, hydrogen sulfide, carbon dioxide and organic acids with sulfate-reducing bacteria, is considered.Materials and Methods. High performance properties of seating surfaces of pipe fittings are provided through anticorrosive plating of alloyed and high-alloyed metals based on iron with the addition of chromium, nickel, cobalt and niobium. The basic weld overlay methods are analyzed: metalarc welding, nonconsumable and consumable-electrode weld facing in shielding gases, submerged arc surfacing. Advantages and disadvantages of surfacing methods implemented in recent years are noted: laser, plasma-powder and plasma-arc methods.Research Results. Taking into account the automation capabilities, a high-tech process of robotic anticorrosive surfacing using a consumable electrode with an additional filler metal feed to the front welding puddle for shielding the thermal effect of the arc, is proposed. Industrial application of the proposed technology requires a set of studies related to assessing the effect of technological parameters on the quality of the deposited layers to provide the required operational characteristics of the fitting.Discussion and Conclusion. It is proposed to carry out the above studies using physical and mathematical modeling of the anticorrosive surfacing, which reduces the time and number of experiments. Therefore, the primary task is to develop a mathematical model of the surfacing process with a consumable electrode with an additional filler wire and transverse vibrations of the welding burner. Such a model should virtually reproduce the surfacing process, as well as its thermal cycle followed by calculating the ratio of the structural components of the deposited metal and the substrate metal. The system of equations of the model should be solved by a special computer program. The algorithm presented for solving this class of problems will allow us to make a sound connection of the technological parameters of the surfacing process and the quality parameters of the formation of the deposited layers, to determine the program for their optimization to provide the required operational properties of pipeline fitting.

The design of a new type of pipe rack for civil construction

At present, the traditional way of placing building pipe fittings has many problems, such as labor, large space occupation, and insecurity, while the shelves on the market are not easy to remove the high pipe fittings and have low efficiency. In this paper, a new type of pipe laying frame is proposed, which consists of adjusting mechanism, taking mechanism and resetting mechanism. It not only optimizes the defects of the common display rack in the market, but also innovates the fixation and arrangement of the internal pipe fittings. It can not only solve the problems existing in the existing building pipe fitting display rack technology, but also reduce the problems and disadvantages in the use process. Under the actual application, it can improve the placement efficiency of the pipe fittings and reduce the staff, so as to improve the practicability of the rack.

Estimation of Minor Loss Coefficient Associated with Fitting of Venturimeter in a Pipe System

Quantification of minor losses associated with a pipe fitting and regular updating is necessary for ensuring the sustainability of the system. In this study, based on simple lab based experiments, the minor loss coefficient associated with a venturimeter fitted in a pipe system is estimated. It is seen that the loss coefficient varies inversely with the increase in the Reynold’s number and can be depicted with a simple mathematical equation.