Fastening Tool Research Articles

PENETRATING CRANIUM INJURY BY A CONCRETE NAIL: CASE STUDY

The article describes a case study, demonstrating the infliction of a single blind penetrating «gunshot» wound to the head with a concrete nail fired from a powder-actuated fastening tool. Forensic examination of the injury caused by atypical projectiles when fired from atypical firearms can be a difficult task. The results of a thorough autopsy examination of the body and the ante-/post-mortem discovery of atypical projectiles (or other foreign objects) in the victim’s body are the prerequisite for correct interpretation of the injury morphological features. Peer Review History: Received: 22 October 2023; Revised: 26 November; Accepted: 29 December, Available online: 15 January 2024 Academic Editor: Dr. Muhammad Zahid Iqbal, AIMST University, Malaysia, drmmziqbal@gmail.com Received file: Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Rima Benatoui,Laboratory of Applied Neuroendocrinology, Department of Biology, Faculty of Science, Badji Mokhtar University Annaba, Algeria. benattouiryma@gmail.com Dr. Owanaro Peter, Nigeria, Department of Clinical Pharmacy and Pharmacy Practice, Faculty of Pharmacy, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria. owonaropeter@gmail.com

МОДЕРНИЗАЦИЯ СТРОИТЕЛЬНО-МОНТАЖНОГО ПИСТОЛЕТА ДЛЯ ДОБЫЧИ ПРИРОДНОГО КАМНЯ

The possibility of mechanizing the operation of wedging for the extraction of natural stone was reviewed. The goal is to reduce the weight of the wedges to several kg and reduce the diameter of the holes in the stone where the wedges are installed. The weight of one hydraulic wedge used is 26 kg, not counting the weight of the hydraulic pump with pressure hoses. Among the options for mechanizing stone mining with wedges, the following approaches are considered – the use of the electro-hydraulic effect; application of liquid nitrogen evaporation in a closed volume; use of electromechanical wedge drive. The fourth option was chosen – modernization of the powder actuated fastening tool for the new task. A calculation has been made for a modernized fastening tool. Several fastening tools chambered for a 7,62 × 54,00 mm rifle cartridge with a charge of moderated propagation gunpowder can split a large stone block. Shallow holes are drilled into the stone block into which wedges are inserted. Measures have been taken to compensate for the recoil of a shot. A shot is fired and the wedges, much larger than a concrete anchor, split the stone. The wedges are reusable. The synchronized operation of several tools is ensured by electric firing from one circuit. A modernized tool with an electric triggering for stone mining can weigh below 3,5 kg. The technical details of the proposal are discussed.

Technological features of OOG transportation by sea transport

The article discusses the features of the transportation of oversized cargo by sea on container ships. The main governing documents and rules for the confirmation and placement of oversized cargo are indicated. The problems are reflected in the guidance documentation, since at the moment it is impossible to take into account all the features of a specific oversized cargo when creating a loading plan and cargo fastening tools on a flat rack. The scheme of placement of oversized cargo on a container ship is given. Options for attaching oversized cargo to a flat rack are considered in detail. The loads are divided into categories, for each of which the methods of fastening are given in accordance with the peculiarities of the geometric shapes of the load and the weight distribution. The conclusion indicates the need to create a software module for standardizing the rules for loading oversized cargo, which will systematize all the characteristics of oversized cargo, calculate the best options for placing cargo on a ship, taking into account the safety requirements and optimality of the cargo plan, reduce accidents during loading / unloading and transportation. It was also noted that the standardization of the loading module for oversized cargo will allow integrating information about the transportation of oversized cargo into the overall system for determining the efficiency and quality of container shipping.

Semi-Automation: A Halfway House?

What are the engineering issues, benefits and trade-offs involved with transitioning from manually-held fastening tools to semi-automated operations?

Design and Analysis of a Robotic End-Effector for Automated Hi-Lok Nut Installation

The automated installation of hi-lok nuts by the robot is an effective way to replace tedious manual labor. For this purpose, an appropriate end-effector needs to be designed to carry out the feeding, alignment and fastening tasks. According to the installation process of hi-lok nuts, a motor driven fastening tool is designed with two parts: the front nut runner and rear driving shaft. The fastening task is modeled based on the force balances in the nut screwing action, which present the nut runner can rotate the nut as well as feed it axially. Then, a feeding-alignment (FA) device is designed to engage the nut feeding for fastening tool. The alignment action is modeled through the force balance about hi-lok nut involved with the nut gripper and nut runner. Finally, a tool end-effector has been built and integrated with an industrial robot. The successful implementation of automated installation of hi-lok nut demonstrates the effectiveness of the proposed installation method and the validation of the designed robotic end-effector.

Research and Application of Locking Strip for Inter-Hexagon Screw in Main Pump for Nuclear Power Station

The loosening of inter- hexagonal screws connecting internal parts in main pump for nuclear power station causes some nuclear safety problem due to medium erosion at present. Aim at the problem, a special locking strip for inter- hexagonal screws is put forward and the structure of the locking strip, the bending process and the forming die of the locking strip are designed and calculated in this paper. Furthermore, the fastening tool of the locking strip is designed, and the feasibility of the locking strip is verified in the experiment so as to improve the anti-loosening reliability. The locking strip for inter- hexagonal bolts can be widely applied to the locking and fastening industry application fields.

Design and Analysis of Fixture for Welding Casing Components of Cross-Flow Turbine

The purpose of this research is to improve the quality of the turbine casing product by using the welding fixture. The method used was to design and make welding fixture of turbine casing welding, test the straightness, alignment, straightness, and analyzes the deviation of measurement results. Based on the design result of welding fixture assembling of cross-flow turbine casing component, it had been obtained prototype welding fixture which can facilitate the assembling process of cross-flow turbine casing component. The conclusions of this research are the quality of cross-flow turbine casing products can be increased along with the small geometry deviations in the cross-flow turbine runners by using a fastening tool. The maximum deviation of the straightness of the turbine wall is 1.6 (wall A) and 0.85 (wall B). The process of assembling the components of the turbine runner is shorter by using a faster welding assembly tool with a better level of accuracy.

Modular fastening system and tool–holder working unit for incremental forming

Incremental forming can be usually unfolded either on CNC milling machine–tools or serial industrial robots. The approach proposed in this paper tackles the problem of designing a modular fastening system, which can be adapted for both above mentioned technological equipment. The fastening system of the sheet–metal workpiece is composed of a fixing plate and a retaining plate. The fixing and retaining plates will be made up of different individual elements, which can be easily repositioned to obtain different sizes of the part. Moreover, the fastening system has to be able to be positioned either horizontally (to be fitted on CNC milling machines) or vertically (to be fitted on industrial robots. The paper also presents the design of a tool–holder working unit which will be fitted on KUKA KR 210 industrial robot. The working unit will be mounted as end–effector of the robot and will bear the punch, driving it on the processing toolpaths.

The Effect of the Fiber of Wood and Connection Tools on the Vibration Characteristics of Gofasa Wood (<em>Vitex cofassus</em>)

The aim of this study was to determine the characteristics of vibration transmission of Gofasa wood (vitex cofassus), which the primary material used in wooden shipbuilding in Maluku. The improvement of the connections of wood has an influence on the stiffness values of the binding system because of its mechanical properties. In this research, the excitation test was carried out on the connection with Radial-Radial (RR), Tangential-Tangential (TT) and Radial-Tangential (RT) fiber direction to see the effect of the orientation of the wood fiber on the vibration characteristics. The excitation test to the specimens using bolt, nail and peg connections was conducted to see the effect of the fastening tool on vibration characteristics. The results of the tests showed that the dynamic stiffness of the RR connection using a bolt had the highest value at the four measurement points exceeding the dynamic stiffness of the material without connections. Dynamic stiffness k of the TT connections using a nail had the highest value and k with the RT joint recorded the highest value using the peg connection tools. This study shows that the determination of the direction of the fiber and the type of connecting devices have an effect on the magnitude of the vibration transmission. This research indicates that vibration characteristic can be using as a reference in determining the appropriate connection tool to be used on wood material based on the fiber direction.

Temporary cavity created by free-flying projectiles propelled from a powder-actuated nail gun

Nails and driving pins discharged from powder-actuated fastening tools bear some special ballistic characteristics. Compared to the usual pistol or revolver projectiles, the sectional density (S) of fastening pins is extremely high. The general prevailing opinion is that the kinetic energy delivered by fastening tools is not high enough to cause a temporary cavity. Therefore, it was the aim of this study to investigate the wound morphology due to fastening bolts discharged from a powder-actuated direct-acting nail gun (where, in contrast to modern piston-type tools, the expanding gases act directly on the fastener) using ballistic soap blocks as simulants. For test shots, a direct-acting powder-actuated nail gun which features three interchangeable barrels (caliber (cal.) 6, 8, and 10 mm) was used. The average kinetic energy was 537, 532, and 694 J for the 6-, 8-, and 10-mm cal. bolts, respectively. Test shots on the ballistic soap blocks demonstrated that free-flying projectiles discharged from direct-acting fastening tools are able to create a temporary cavity.

Fastening tool tracking system using a Kalman filter and particle filter combination

This paper presents a position tracking system which estimates the position of the tip of a fastening tool. The proposed system uses a Kalman filter (KF) and particle filter (PF) combination to synthesize measurements from an inertial measurement unit (IMU) and a position sensor. The KF part is used to estimate the position of the centre of mass of the tool, and the PF is used to estimate the orientation of the tool. In addition, a rule-based logic system is used to reduce angular velocity measurement error and identify the fastening action of the tool. The proposed system was validated experimentally using various scenarios representative of assembly tasks in a factory environment. The experiment results show that the proposed system can accurately identify the fastened bolt even when the angular velocity measurement is not accurate provided that a large enough number of particles is used. In addition, even when there are multiple possibilities for fastened bolt positions, the experimental results show that the proposed system can correctly identify the fastened bolt by utilizing the accumulated position error of each particle.

Ballistic parameters and trauma potential of direct-acting, powder-actuated fastening tools (nail guns)

Since their introduction in the 1950s in the construction and building trade, powder-actuated fastening tools (nail guns) are of forensic and traumatological importance. There are countless reports on both accidental and intentional injuries and fatalities caused by these tools in medical literature. While the ballistic parameters of so-called low-velocity fastening tools, where the expanding gases act on a captive piston that drives the fastener into the material, are well known, ballistic parameters of "high-velocity" tools, which operate like a firearm and release the energy of the propellant directly on the fastener, are unknown. Therefore, it was the aim of this work to investigate external ballistic parameters of cal. 9 and 6-mm fastening bolts discharged from four different direct-acting nail guns (Type Ideal, Record Piccolo S, Rapid Hammer R300, Titan Type 1). Average muzzle velocity ranged from 400 to 580 m/s, while average kinetic energy of the projectiles ranged from 385 to 547 J. Mean energy density of the projectiles ranged from 9 to 18 J/mm(2). To conclude, this work demonstrates that the muzzle velocity of direct-acting high-velocity tools is approximately five times higher than the muzzle velocity of piston-type tools. Hence, the much-cited comparison to the ballistic parameters of a cal. 22 handgun might be understated and a comparison to the widespread and well-known cal. 9 mm Luger might be more appropriate.

Research on Force Feedback-Based Tool Operation in Virtual Assembly

To verify the accessibility and workspace of tool operation in virtual assembly system, this paper presented a tool-part operation method based on force feedback. According to characters of common tool-part operations, standard fastening tools and parts were modeled using features and parameters at initial stage. Then operator was enabled to conduct different kinds of fastening and unfastening operations in virtual assembly system by three steps namely identification, interactive positioning and operation. With feedback force, the operator can feel corresponding motion constraints of tool during virtual fastening and unfastening operation, so the immersion of virtual assembly operation is promoted.

A Fastening Tool Tracking System Using an IMU and a Position Sensor With Kalman Filters and a Fuzzy Expert System

This paper utilizes an intelligent system which incorporates Kalman filters (KFs) and a fuzzy expert system to track the tip of a fastening tool and to identify the fastened bolt. This system employs one inertial measurement unit and one position sensor to determine the orientation and the center of mass location of the tool. KFs are used to estimate the orientation of the tool and the center of mass location of the tool. Although a KF is used for the orientation estimation, orientation error increases over time due to the integration of angular velocity error. Therefore, a methodology to correct the orientation error is required when the system is used for an extended period of time. This paper proposes a method to correct the tilt angle and orientation errors using a fuzzy expert system. When a tool fastens a bolt, the system identifies the fastened bolt using a fuzzy expert system. Through this bolt identification step, the 3-D orientation error of the tool is corrected by using the location and orientation of the fastened bolt and the position sensor outputs. Using the orientation correction method will, in turn, result in improved reliability in determining the tool tip location. The fastening tool tracking system was experimentally tested in a lab environment, and the results indicate that such a system can successfully identify the fastened bolts.

Modeling of the hand–arm system for impact loading in shear fastener installation

The aim of this study is to model the hand–arm system during fastening operation using shear fasteners. This fastening operation has considerable dynamic forces caused by the impact delivered to the hand–arm at the end of the operation because of fastener shear-off. The hand–arm is modeled as a rotational single-degree-of-freedom system. The values of the model parameters are obtained using the magnitude of compliance spectrum calculated from the measured torque and angular displacement data, which are obtained while installing fasteners on a fixtured experimental setup, and by a non-linear least-square curve fitting technique. The experimental setup facilitates transferring the torque from a torque driver to a fastening tool handle held by the subject. The identified parameter values are found consistent for the trials conducted under same test conditions. Strong agreements are seen between the predicted responses using the model and the measured responses. Relevance to industry This study is useful in tool selection and workplace design for assembly shop floors where hand-held power tools are commonly used. It demonstrates a systematic approach in predicting the motion of an operator's hand–arm for a given torque impulse produced by a fastening tool. The predicted motion can be used for further analysis to determine the detrimental effect it may have in causing cumulative trauma disorders.

Real-time detection of grip length deviation during pull-type fastening: a Mahalanobis–Taguchi System (MTS)-based approach

In this study, a Mahalanobis–Taguchi system (MTS)-based diagnostic and root cause analysis scheme for monitoring grip length of pull-type fasteners in real-time is presented. The proposed approach is implemented on a fastening tool integrated with a strain gage, a linear variable differential transformer, a pressure sensor, and a mote for wireless communication. Experiments show that the process signature of strain-over-displacement ratio versus displacement has unique features that can be used to determine the grip length related deviations. The proposed approach takes as input various characteristics, such as peak strain, peak displacement, and depth and width of a bowl-shaped dip on the process signature in order to make real-time decisions. The experiments show that the proposed approach is effective in determining grip length deviations and in communicating the decision in real-time via a wireless network to a base station. Overall, the proposed architecture has merits to (1) detect quality problems in real-time during the fastening process and (2) reduce post-process inspection, thereby improving quality while reducing cost. In addition, the approach facilitates 100% data collection on each fastener as opposed to traditional statistical process control (SPC) techniques, which rely on sampling.

Lighter, faster and stronger electric fastening tool introduced by Stanley

Stanley Assembly Technologies has introduced the new EA series tools to the company range of DC electric threaded fastening tools.

Development of a Dynamic Load-Deflection Apparatus for Elastomeric Materials

Abstract A method of experimentally determining the dynamic load-deflection behavior of elastomeric impact absorbers is developed. Particular attention was given to impact absorbers (bumpers) used in pneumatic fastening tools, and the dynamic load-deflection apparatus developed here closely replicated actual service conditions. Cylindrical specimens and actual bumpers were fabricated from epichlorohydrin and nitrile elastomers, two materials commonly used in the bumper application. The dynamic behavior of thin circular disks is also studied and brief comparison with the Split Hopkinson Pressure Bar technique is given.

Stud Guns Revisited: Report of a Suicide and Literature Review

Stud guns (powder-actuated fastening tools) are a commonly used construction tool. Accidental injuries and fatalities are no longer frequent, presumably because of current safety features and practices. A case of an intentional fatal wound (suicide) is described. A literature review of stud gun injuries is also presented.

Noise reducer for powder activated fastening tool

A noise reducer for a powder actuated fastening tool comprises a barrel including inner and outer cylindrical walls which are radially spaced to define a gas expansion chamber between them. The chamber is adapted to receive combustion gases through ports or passages in the inner wall, and the gases may be exhausted from the chamber in any appropriate manner, preferably at a location adjacent the front end of the tool. The outer wall of the barrel can thus be made to slidingly fit within the tool receiver, while porting of the expansion chamber can be such as to induce a favorable flow pattern to the combustion gases passing therethrough.