Pipe Thread Research Articles

Defect Detection for Drill Pipe Thread Based on Eddy Current Testing

Defect Detection for Drill Pipe Thread Based on Eddy Current Testing

Study on Low-Temperature Deposition of Diamond-like Carbon Film on the Surface of Bionic Joint Thread and Its Properties

The double-connection structure of bionic joints of mining drill pipes has solved the problem of drill drop caused by fatigue cracks. However, with low-melting-point elastic–ductile alloy filling in the bionic joint, the thread on the joint cannot be hardened by high-temperature surface hardening treatments such as quenching and nitriding, making it prone to thread gluing or excessive wear. In this paper, the feasibility of diamond-like film deposition on the surface of a bionic drill pipe thread was studied. A tungsten transition film was used to improve the thickness of the film and the interfacial bond strength between the film and the substrate. The test results show that the total thickness of the DLC film is about 3~5 μm, the roughness is less than 2 μm, the hardness of the film reaches 24.4 GPa, the friction coefficient is 0.04, and the critical load is 56 N. SEM and EDS analyses show that the tungsten film and the bionic joint thread form a metallurgical structure. The morphology of the diamond-like carbon film is uniform and dense, and there is no obvious stratification between the substrate material. The joint with a diamond-like coating treatment has a longer service life than joints receiving conventional high-temperature nitriding treatment.

THREAD UNRAVELED: INVESTIGATING FATIGUE FAILURE IN DRILL PIPE SS105 – A CASE STUDY

This case study delves into the intricate details of fatigue failure observed in the drill pipe SS105 thread. Through meticulous investigation and analysis, the study aims to unravel the complexities surrounding the failure mechanism, exploring contributing factors and potential preventive measures. The findings provide valuable insights for the oil and gas industry, enhancing understanding and mitigating risks associated with drill pipe thread fatigue failure.

PSIV-26 Development of a Controlled Exposure Particulate and Oxidative Radical Mask for Causality Experiments Investigating Smoke Exposure on Livestock Animals

Abstract Understanding and mapping the specific effects of smoke inhalation on cattle performance provides strategic insights for producers and policy makers to better prepare or adjust when faced with sporadic or even seasonal reductions in air quality. As of now, no current studies have attempted to investigate the effects of seasonal fires on performance and health adequately in livestock while addressing obvious confounding effects, controlling exposure, and examining fuel for differential oxidative radicals and particulate smoke. Herein, we propose the design of the first cost-effective controlled system for investigating smoke, particulate matter, and varied oxidative radicals through a pre-mixing chamber. The mask main body is constructed from 8” nominal diameter schedule 40 PVC pipe. The endcap was designed in an online CAD software to provide an interface for standard 2 ⅞” bulkhead fittings and was produced via additive manufacturing (3D printing). A silicone SCUBA neck seal was used to line the face orifice and is the component that directly contacts the animal’s nose and mouth. A neoprene rubber sheet and an insulation hose were used as padding under the silicone seal to help maintain an airtight connection and animal comfort when the mask is worn. Bulkhead fittings used provide 1 ½” female national pipe thread connection to allow for modular connection of inlet and outlet hoses, check valves for airflow isolation, filters, or any number of connections can be made via these gasket sealed fittings, making this platform extremely adaptable. In its shown configuration, 3D printed adapters were made to attach 4” suction hose to 2” socket union joints for quick connect/disconnect functionality. An inlet and outlet gas/smoke flow regulator are attached to a mixing chamber where particulate and chemical composition sensors are utilized to deliver the desired composition of smoke delivered to the animals. Negative pressure fans and pumps regulate the flow to the animals and are utilized for exposure of smoke in time-specific intervals. An additional fully 3D printed version enables the mask design to be lower in weight through regulation of the density of the internal matrix, and after an initial investment in the equipment also represents a cost-efficient approach to generating multiple masks. Understanding the effects of particulate and reactive oxidative molecules on livestock health and performance requires the study of a controlled exposure, the system presented herein represents a viable and cheap alternative for bettering a mechanistic model and understanding of the effects of smoke on animal health and performance. Ultimately, the proposed mask paired with currently available sensors permit for the controlled exposure of smoke particulate with different chemical compositions for accurate evaluation of prolonged exposure effects on livestock.

Nanoarchitectonics and performance evaluation of a Fe3O4-stabilized Pickering emulsion-type differential pressure plugging agent

Abstract With the rapid growth of natural gas consumption capacity, the important role of gas storage in seasonal peak shaving and emergency response is gradually emerging. Long-term forced production and injection of gas storage will lead to problems such as wellhead equipment leakage and string seal failure. Replacing the string is not only costly but also takes a long time. Aiming at thread leakage caused by multiple rounds of forced production and injection in gas storage, a Pickering emulsion differential pressure plugging agent with a self-sealing function under a certain pressure difference was developed. We selected carboxyl nitrile latex with a self-polymerization function and modified the nano-stabilizer Fe3O4@SiO2. The Pickering differential pressure plugging agent with excellent plugging performance was prepared by the combination of modified particles and non-ionic emulsifier OP-10. The plugging test was carried out for the simulated oil pipe thread. When the leakage rate was 50 mL/min, no leakage occurred under a pressure of 20 MPa after plugging. The differential pressure plugging agent is expected to achieve plugging without moving the pipe string and rebuild the integrity of the wellbore.

Study on formability of duplex steel expansion pipe and its threaded joints

The threaded joint of equal well-diameter-expansion pipe is prone to fracture and leakage after expansion forming. The structural integrity and material selection of the expansion pipe threaded joint are the main difficulties. Taking dual-phase steel and other well-diameter expandable casings as the research object, a method combining finite element simulation and experimental verification is used to construct an enhanced constitutive model. Firstly, three kinds of reinforced constitutive models are constructed, and then finite element software is used for simulation, combined with experiments to analyze the axial length of the pipe, pipe wall thickness, thread clearance, material hardness, plastic toughness and microstructure. The results showed that after expansion the top and root of the threaded area of the tube after expansion have greatest change and the residual stress is relatively high. Microhardness and Charpy impact tests were carried out on the pipes before and after expansion to study the changes in hardness and toughness. It can be found that the toughness of the expansion pipe has decreased, and although the wall thickness will be reduced, the strength of the pipe will be significantly increased, which is the effect of work hardening. The topography of the crack surface is nearly identical over the entire range of expansion ratios considered in this study. In addition, the microstructure of the unexpanded and expanded tubes is similar, consisting of ferrite and austenite. This paper provides a theoretical reference for engineering practice.

Pipe Thread Parameter Detection System Based on Machine Vision

In order to achieve non-contact pipe thread detection with high-precision, high-efficiency and make the use of pipe threads safer, using machine vision and image processing technology to measure and analyze the geometric parameters of pipe threads. The projection matrix and distortion coefficient of the camera are obtained by Zhang Zhengyou’s calibration method, and the distortion coefficient is used to correct the distortion of the collected image. After that, grayscale processing is performed on the RGB (Red, Green, Blue) image obtained by the collection and correction, fusion filtering and denoising, threshold segmentation to obtain the binary image, and then the Canny operator is used to detect the thread edge information on the binary image. Then the pipe thread parameter measurement algorithm is proposed based on the extracted pipe thread image characteristics. Finally, the feasibility of the measurement algorithm is verified by using the measured data of 60 sets of pipe threads. The test results show that the measured values of tooth height and crest height obtained by this algorithm are concentrated near the standard value, with high accuracy and precision, and the overall data fluctuation is small.

Study of Tapered Threads Parameters Affecting the Quality of the Oil Pipeline Connection

Introduction. With the growth in the production and transportation of gas and oil, the urgency of the problem of tightness of the connection of pipes of the oil and gas range increases. The most common are coupling and streamline threaded connections. Threads of the buttress type, conical trapezoidal, and triangular threads are used. The tightness of the connection depends directly on their quality. The production of pipes and couplings is influenced by many factors. Examples include technological heredity, rigidity of technological equipment, its setting and resetting. The required connection quality is provided by the quality of the elements. The assembly should take into account the possibility of complete interchangeability. The second recommended option is a group assembling. In all cases, control operations are mandatory. The paper presents the results of studies on the distribution of pipe and coupling thread quality parameters in the batch.Materials and Methods. Fragments (tubular parts) of casing pipes with trapezoidal thread and increased tightness (CPTT) and with trapezoidal thread of the buttress profile were studied. They were randomly selected from different batches. When measuring, the samples were fixed in the chuck of 1I611P lathe. The measuring instrument was a clock type 0 accuracy class indicator with a stand. Generally accepted statistical methods were used to evaluate the data obtained.Results. The experiments have found how the tightness of the connection through the method of complete interchangeability is affected by the radial runout of the surfaces of the thread profile tops, the pipe chamfers, and the sealing belt.Discussion and Conclusions. Significant deviations of the values of the thread parameters from the permissible ones were found, which might cause a leak in the connection. Obtaining a high-quality and reliable connection is possible when assembling by the method of incomplete or group interchangeability.

Design of a New Puncture Needle for Trocar

To develop a new type of puncture needle for indwelling needle, which can overcome the performance problems of the existing puncture needle, reduce producing cost, and enhance clinical operability. In this design, solid needle thread is used to replace the traditional hollow pipe thread, three cutting edges are used to replace the existing two cutting edges, and the shaft edge form (the needle tip is on the needle thread's axis) is used to replace the original back blade or edge blade; the slot on the side of the solid core wire is used to replace the hollow and side hole on the traditional pipe. Finally, a new solid core puncture needle is formed by a section of solid core steel wire with a spiral groove, the cross-section of which is a circular slotted needle with a triangular shape at one end. Through the comparative analysis of stiffness mutation and puncture force in the experiment, the characteristics and advantages of new puncture needle are reflected. The new solid core needle can meet the need of puncture in the course of treatment, and can avoid the potential risk caused by the rigidity mutation of the needle used in the traditional indwelling needle, at the same time, it also has the space to reduce the demand of needle diameter, that means it has the potential to develop smaller needle products. The new type of trocar puncture needle, from hollow to solid core, can not only meet the basic requirements of puncture and observation of blood return, but also can avoid the risk of traditional puncture needle due to stiffness mutation, the utility model also has the advantages of better performance (less puncture force) and larger expansion space.

Study on the Position Deviation between the Iron Roughneck’s Spin-Rollers and the Drilling Tool

The spinner mechanism is one of the main working mechanisms of the iron roughneck, which is used to realize the rapid screwing-in or screwing-out of the drill pipe thread. The main problems of the spinner mechanism and the existing solutions are analyzed in this paper, and the spinner mechanism driven by a single hydraulic cylinder and transmitted by a wedge plate is designed. The upper and lower drilling tools are not concentric and affect the spin effect when the spinner mechanism works, and to address this problem, the influence of deviation in different directions is analyzed, and it is proposed that the lateral position deviation of drilling tools is the key factor affecting the spin performance. The relationship between the position deviation of the spin-roller and the position deviation of the drilling tool is established and solved. A method to reduce the lateral position deviation of drilling tools is proposed, and the effectiveness of this method is verified by experiments. The analysis shows that a spinner mechanism with a single follow-up roller easily causes the lateral position deviation of the drilling tool; the deviation of the spin-roller increases with the increase of the lateral deviation of the drilling tool, and the increase of the longitudinal deviation is more obvious; and with the increase of the drilling tool’s diameter, the deviation increases further. The symmetrical double follow-up roller structure can effectively reduce the lateral deviation of drilling tools and spin-rollers and ensures centering performance and the realization of reliable spin.

Study on Dynamics of Hydraulic Control System for Automatic Loading and Unloading of Drill Pipe of Geological Drilling Rig

With the increasing demand for resources, the task of the geological survey is growing rapidly. The automatic geological drilling rig, which can improve the efficiency of the geological survey, has become the mainstream development direction. In this study, the hydraulic control system for the automatic screw up and screw down of an automatic drilling rig is studied. Through the establishment of mathematical models such as the four-way slide valve controlled asymmetric cylinder model, drill pipe thread stress model, and steel wire rope elastic model, the hydraulic valve is used to limit the pressure of the hydraulic cylinder, closed-loop control to control rotation speed, and power head floating to prevent screw damage and realize the automatic control of drill pipe up and down of a geological drilling rig. The hydraulic control system is simulated by AMESim software. The simulation model verifies the mathematical model. It is concluded that the maximum transient force of steel wire rope is caused by the elastic coefficient K of steel wire rope, but the magnitude is independent of K. The transient force is the periodic motion force. The displacement, velocity, and acceleration of load are periodic functions related to time. By installing a small flow load sensing valve, the displacement of an asymmetric hydraulic cylinder can be accurately controlled, and then, the displacement of the drilling rig powerhead can be controlled. The combined action of drill pipe speed and power head displacement is adopted, and the power head displacement is followed by PID control through the feedback value of the drill pipe speed, which can realize the automatic loading and unloading of drill pipe and reduce the damage of drill pipe screw during loading and unloading of drill pipe. The research results of this study can provide a theoretical reference and design basis for the follow-up development of an automatic drilling rig.

Detection System Development of Drill Pipe Thread Based on ACFM Technique

As an important connection method between drill pipes, the thread is prone to fatigue cracks and stress corrosion cracks due to long-term exposure to complex forces and corrosive environments. The thread crack detection system of drill pipe based on altering current field measurement (ACFM) is proposed. The crack detection model of the drill pipe thread using ACFM is developed by the finite element software COMSOL. The distribution of the induced magnetic field above the thread is extracted. The relationships between the characteristic signal and the depth and angle of the crack are analyzed. The drill pipe thread detection probes and the detection system are established, and different types of cracks on two different specifications of threads are detected. The experimental results show that the detection system can achieve full coverage detection of the thread crest and root, and cracks at different angle can be identified effectively on the thread.

Application of Hydraulic Control Make-up and Rreak-up Device in Improvement Design of Drilling rig

Tunnel drilling rig is widely used in coal mine gas drainage, hidden disaster detection and other construction. In view of the serious problem of thread wear when loading and unloading drill pipe thread of underground drilling rig in coal mine, a pure hydraulic control device is developed. By adjusting the corresponding angle parameters of the hydraulic control device, two actions of rotary feeding can be realized, and the thread can be loaded and unloaded automatically according to the thread pitch. The design of the device is completed, and the structure is applied to the improved design of ZDY750L and ZDY2-300LM drilling rigs. The matching control of feed and rotation of the two drilling rigs when loading and unloading the drill pipe is realized, which can reduce the wear of the drill pipe thread when the full hydraulic drilling rig is loading and unloading, and provides a new idea and solution for the implementation of the full hydraulic drilling rig automatic loading and unloading.

Augmented Reality for Pipe Thread Connection Type Training

The process of extracting oil and gas is carried out by drilling with a depth of more than 200 meters below the surface of the ground, so one steel pipe is needed to run the process. The manufacture of steel pipes for the opening process has special standards, one of which is a long pipe. To reach a depth of 200 meters below the ground level, a pipe connection is needed to reach that height. The method of connecting the pipes is called the Thread Connection Type. This method has more than 20 types of threads to be applied in pipe joints. To facilitate the discussion of the types of threads and their specifications, we need a technology that can be used interactive and mobile learning media to deliver detailed information on the type of thread. The author uses the use of Augmented Reality (AR) technology to be applied as an Android-based training media that can facilitate the existing Connection Thread along with special specifications with 3D visualization. This study aims to measure the validity and practicality of using ISO 25010 (in terms of functional suitability, performance efficiency, portability and usability) of learning media so that it is easier to understand and practical. The study consisted of two parts: 1) Validity by experts (5 experts), 2) Practicality by trainees or employees (16 participants) using the USE Questionnaire instrument. Furthermore, in application development using the Multimedia Development Life Cycle (MDLC) method as its development method. As a result, the application was declared feasible with the results of the percentage of experts Validity of 96% and Practicality by employees of 79%.

Thread milling errors

The study shows that thread milling (including internal threads) is one of the most forward-looking technologies that offers max thread cutting performance. The reasons are the shortest cut-in path equal to the thread depth, and the full thread profile machining time equal to the period of one revolution of the workpiece. The paper highlights that thread milling is an efficient, general-purpose machining process. In this study, we solved the thread profile error estimation problem. Thread milling with parallel workpiece and cutter axis was investigated with a milling simulation model. The optimal thread milling tool parameters for internal thread machining were found. The method efficiency was proven by measuring undercuts and overcuts in pipe thread milling. For instance, the thread error (overcuts/undercuts measured flatwise to the thread profile) diametral compensation does not exceed 0.0268 mm while the pipe thread tolerance G1.25`` is 0.36 mm.

Analysis of fatigue behaviour of drill pipe on pin-box connection

Drilling is one of the costliest and risky activities in oil and gas industry due to complexity of interactions with downhole formation. Cyclic loads while drilling cause the initiation and growth of cracks in oil tubulars. This phenomenon, known as fatigue, results in permanent reduction of the failure-free service envelope of a certain tubular. Further, most of the drill string failures are triggered by fatigue, which results from repetitive cyclic bending loads and stresses in tensile or buckled drill strings. Fatigue is a cumulative and non-reversible condition induced by repetitive cyclic bending loads and tensile or buckled drill pipe stresses. Fatigue exists even though cyclic tension of the drill pipe material is much lower than static strength limit. Present work investigates fatigue capacity of the 4” WT38 drill pipe connection where cracks have been observed. In accordance with the geometry of connection, a hot spot stress from bending moment is calculated in the crack location in the first thread (upper) of the pin. The DNVGL-RP-C203 SN-curve B1 “in air” is used as relevant fatigue SN curve for the drill pipe thread location. Finite element method (FEM) is employed in modeling and analyzing of drill pipe on pin-box connections. With this method, various connections can be investigated relatively faster and cheaper compared with experimental tests. It is found that the fatigue failure may have been caused as a result of the cyclic load level and number of load cycles. A detailed discussion of the fatigue damage assessment concludes the paper.

Simulation research on measurement method of geometric parameters of non-contact pipe thread

In order to ensure that the pipe thread exerts its good sealing and transmission performance in the oil and gas pipeline, it is essential to judge the geometric parameters of the pipe thread. The experiment uses the 60° standard sealed pipe thread of model NPT1/2 as the research target, the machine vision technology is used to make non-contact measurement of the pipe thread geometry, LABVIEW is used as the software development platform to analyse the processed thread image. Finally, the parameters such as pitch, thread angle, taper, and thread height are simulated and measured to obtain the qualification conclusion.

Study on dynamic characteristics analysis of CNC pipe thread lathe based on the energy of modal effective mass

Owing to the modal analysis of complex structure system exist in the problems such as the local mode cannot be identified and the overall modal vibration mode cannot be extracted, this study deduces a formula of modal effective parameters based on the kinetic energy and introduces to the simulation of mechanical characteristics of the SCK230 CNC pipe thread repair the lathe bed. The simulation shows that this method can identify the local mode of three directions effectively, and determines whether the numbers of solved modalities satisfy the requirement of precision. In order to improve the natural frequencies of the bed and analyse the influence of the opening of the bed on its dynamic performance, three optimisation schemes are proposed based on this, and verified the feasibility of the optimisation scheme. Through structural optimisation, improve the dynamic characteristic of the lathe bed and reduce the manufacturing cost, and the optimisation of the structure can be achieved without experimental modal analysis.

Dynamic characteristics analysis of CNC pipe thread lathe based on energy balance

Dynamic characteristics analysis of CNC pipe thread lathe based on energy balance

A Fast and On-Machine Measuring System Using the Laser Displacement Sensor for the Contour Parameters of the Drill Pipe Thread.

The inconvenient loading and unloading of a long and heavy drill pipe gives rise to the difficulty in measuring the contour parameters of its threads at both ends. To solve this problem, in this paper we take the SCK230 drill pipe thread-repairing machine tool as a carrier to design and achieve a fast and on-machine measuring system based on a laser probe. This system drives a laser displacement sensor to acquire the contour data of a certain axial section of the thread by using the servo function of a CNC machine tool. To correct the sensor’s measurement errors caused by the measuring point inclination angle, an inclination error model is built to compensate data in real time. To better suppress random error interference and ensure real contour information, a new wavelet threshold function is proposed to process data through the wavelet threshold denoising. Discrete data after denoising is segmented according to the geometrical characteristics of the drill pipe thread, and the regression model of the contour data in each section is fitted by using the method of weighted total least squares (WTLS). Then, the thread parameters are calculated in real time to judge the processing quality. Inclination error experiments show that the proposed compensation model is accurate and effective, and it can improve the data acquisition accuracy of a sensor. Simulation results indicate that the improved threshold function is of better continuity and self-adaptability, which makes sure that denoising effects are guaranteed, and, meanwhile, the complete elimination of real data distorted in random errors is avoided. Additionally, NC50 thread-testing experiments show that the proposed on-machine measuring system can complete the measurement of a 25 mm thread in 7.8 s, with a measurement accuracy of ±8 μm and repeatability limit ≤ 4 μm (high repeatability), and hence the accuracy and efficiency of measurement are both improved.