scholarly journals Stability of Physically-Loaded Helical Springs used in Smart Fork Lift

2019 ◽  
Vol 9 (2) ◽  
pp. 3839-3845
Keyword(s):  
Heat Treatment ◽  
Spring Steel ◽  
Original Form ◽  
Helical Spring ◽  
Storage Devices ◽  
Helical Springs ◽  
Conical Shape ◽  
Steel Material ◽  
Compression Springs ◽  
Mechanical Devices

In the following section, the behavior of helical compression springs is considered in smart fork lift (established in previous work). We have used commonly used cylindrical and conical shape helical spring as storage devices in which stability defined in term of load-gains, deflections and evaluation of spring-rates. Springs’ rates of both springs were compared on a common platform. Initially both springs (helical-conical) was prepared from the coiled wires. These prepared springs also known as coil springs which regain its original form and position when distorted by the loaded in smart fork-lift apparatus. These coils springs here developed by the applying the heat treatment and quenching processes on the galvanized spring steel material by using the threaded shape fixtures. This prescribed work focused on effect of physically-loaded gains by cylindrical and conical shaped helical spring in smart fork lift. Here, springs worked as mechanical devices to bear the lifting load which differed here greatly in strength and in size depending on changing its parameters. Both the cylindrical and conical shape was made of helically coiled wires with constant clearance between the active coils and able to absorbed external counteracting loads applied against each other in their axis. One direction deformation in axially format was considered.

Analysis and Synthesis of Conical Coil Springs

2021 ◽  
Author(s):  
Harshkumar Patel ◽  
Hong Zhou
Keyword(s):  
Coil Spring ◽  
Spring Rate ◽  
Helical Springs ◽  
Compression Spring ◽  
Spring Wire ◽  
Coil Diameter ◽  
Constant Pitch ◽  
Analysis And Synthesis ◽  
Compression Springs ◽  
Mechanical Devices

Abstract Springs are mechanical devices that are employed to resist forces, store energy, absorb shocks, mitigate vibrations, or maintain parts contacting each other. Spring wires are commonly coiled in the forms of helixes for either extension or compression. Helical springs usually have cylindrical shapes that have constant coil diameter, constant pitch and constant spring rate. Unlike conventional cylindrical coil springs, the coil diameter of conically coiled springs is variable. They have conical or tapered shapes that have a large coil diameter at the base and a small coil diameter at the top. The variable coil diameter enables conical coil springs generate desired load deflection relationships, have high lateral stability and low buckling liability. In addition, conical compression springs can have significantly larger compression or shorter compressed height than conventional helical compression springs. The compressed height of a conical compression spring can reach its limit that is the diameter of the spring wire if it is properly synthesized. The height of an undeformed conical coil spring can have its height of its spring wire if the spring pitch is chosen to be zero. The variable coil diameter of conical coil springs provides them with unique feature, but also raises their synthesis difficulties. Synthesizing conical coil springs that require large spring compression or small deformed spring height or constant spring rate is challenging. This research is motivated by surmounting the current challenges facing conical coil springs. In this research, independent parameters are introduced to control the diameter and pitch of a conical coil spring. Different conical coil springs are modeled. Their performances are simulated using the created models. The deflection-force relationships of conical coil springs are analyzed. The results from this research provide useful guidelines for developing conical coil springs.

Analysis of open Coil Helical Spring used in Vehicles

2017 ◽  
Vol 3 (10) ◽  
Author(s):  
Sameer Singh ◽  
Shyam Birla ◽  
Neeraj Kumar Nagaych
Keyword(s):  
Titanium Alloy ◽  
Carbon Fibre ◽  
Dynamic Loading ◽  
Spring Steel ◽  
Fibre Material ◽  
Helical Spring ◽  
Carbon Fibre Material ◽  
Suspension Spring ◽  
Steel Material

 In this paper suspension spring of a 160cc 2-wheeler is analyzed and optimized for its performance. For this study the diameter and the material of the coil wire for suspension is changed and its effect is noted. In this study three materials were studied that is ASTM A227 hard drawn spring steel material, carbon fibre Material and titanium alloy. The results were obtained for all of these materials and based on the results it can be said that spring made of carbon fibre material gives the best results. The springs were tested under both static as well as dynamic loading, and in all of the tests Carbon fibre spring proved to be best.

Modeling, Prototyping, and Testing of Helical Shape Memory Compression Springs With Hollow Cross Section

2010 ◽  
Vol 132 (6) ◽  
Author(s):  
Igor Spinella ◽  
Eugenio Dragoni ◽  
Francesco Stortiero
Keyword(s):  
Shape Memory ◽  
Cross Section ◽  
Helical Spring ◽  
Lower Mass ◽  
Hollow Section ◽  
Sma Actuators ◽  
Helical Springs ◽  
Compression Springs ◽  
Sma Helical Spring ◽  
Mechanical Actuation

Shape memory alloys (SMAs) are used in many applications as actuators. The main drawbacks that limit the use of the SMAs in the field of mechanical actuation are the low mechanical bandwidth (up to a few Hertzs) and the unsatisfactory stroke (several millimeters). This paper contributes to enhancing the performances of SMA actuators by proposing a new SMA helical spring with a hollow section. The hollow spring is modeled, then it is constructed, and finally it is tested in compression to compare its performances with those of a spring with a solid cross section of equal stiffness and strength. Emptied of the inefficient material from its center, the hollow spring features a lower mass (37% less) and an extremely lower cooling time (four times less) than its solid counterpart. These results demonstrate that helical springs with a hollow construction can be successfully exploited to build SMA actuators for higher operating frequencies and improved strokes.

scholarly journals Heat Treatment of Cold Formed Springs Made from Oil Hardened and Tempered Spring Steel Wire

2017 ◽  
Vol 892 ◽  
pp. 16-20
Author(s):  
Veronika Geinitz ◽  
Ulf Kletzin
Keyword(s):  
Heat Treatment ◽  
Mechanical Characteristics ◽  
Steel Wire ◽  
Spring Steel ◽  
Treatment Technology ◽  
Cold Forming ◽  
Steel Wires ◽  
Heat Treatment Technology ◽  
Compression Springs

The heat treatment after cold forming is used to decrease the residual stresses of springs, but the mechanical characteristics of the spring steel wires alters, too. This presentation describes the influence of the heat treatment technology (oven equipment, temperature, duration,…) to the properties and quality of helical compression springs made from oil hardened and tempered spring steel wire.

VHCF Strength of Helical Compression Springs - Influence of Heat Treatment Temperature before Shot Peening

2015 ◽  
Vol 664 ◽  
pp. 140-149
Author(s):  
Isabell Brunner ◽  
Desislava Veleva ◽  
Jörg Beyer ◽  
Matthias Oechsner
Keyword(s):  
Heat Treatment ◽  
Crack Initiation ◽  
Shot Peening ◽  
Heat Treatment Temperature ◽  
Fracture Behaviour ◽  
Steel Wire ◽  
Fatigue Tests ◽  
Treatment Temperature ◽  
Spring Steel ◽  
Compression Springs

Previous fatigue tests show that the heat treatment temperature has a significant influence on high cycle fatigue behaviour of helical compression springs. In order to investigate the effect of the heat treatment temperature on the fracture behaviour and the cyclic life, fatigue tests in the very high cycle regime (VHCF) were conducted.The tested springs were manufactured from oil hardened and tempered SiCr-alloyed valve spring steel wire with a diameter of d = 1.6 mm. After winding and grinding of the spring endings, the springs were heat treated at either 360°C or 400°C for 30 minutes. In order to generate compressive residual stresses in the surface area, the springs were shot peened. After shot peening, the springs were again annealed at 240°C for 30 minutes.Fatigue tests were conducted at 40 Hz using a special spring fatigue device. Up to 900 springs were tested simultaneously at various stress levels to 5∙108or 109cycles. Fractured springs were investigated by means of a stereomicroscope as well as a scanning electron microscope to analyse the fracture behaviour and failure mechanisms. The vast majority of the springs show crack initiation at the surface at the inner side of the coil. Less frequently, crack initiation occurs at subsurface locations. Our results show that heat treatment at a temperature of 360°C leads to four times more subsurface cracks than at a temperature of 400°C and reduces the overall fatigue life time.

scholarly journals X-ray Determination of Compressive Residual Stresses in Spring Steel Generated by High-Speed Water Quenching

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1154
Author(s):  
Diego E. Lozano ◽  
George E. Totten ◽  
Yaneth Bedolla-Gil ◽  
Martha Guerrero-Mata ◽  
Marcel Carpio ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Residual Stresses ◽  
High Speed ◽  
Spring Steel ◽  
X Ray Diffraction ◽  
Laboratory Equipment ◽  
X Ray ◽  
Water Chamber ◽  
Hardened Case ◽  
Compressive Residual Stresses

Automotive components manufacturers use the 5160 steel in leaf and coil springs. The industrial heat treatment process consists in austenitizing followed by the oil quenching and tempering process. Typically, compressive residual stresses are induced by shot peening on the surface of automotive springs to bestow compressive residual stresses that improve the fatigue resistance and increase the service life of the parts after heat treatment. In this work, a high-speed quenching was used to achieve compressive residual stresses on the surface of AISI/SAE 5160 steel samples by producing high thermal gradients and interrupting the cooling in order to generate a case-core microstructure. A special laboratory equipment was designed and built, which uses water as the quenching media in a high-speed water chamber. The severity of the cooling was characterized with embedded thermocouples to obtain the cooling curves at different depths from the surface. Samples were cooled for various times to produce different hardened case depths. The microstructure of specimens was observed with a scanning electron microscope (SEM). X-ray diffraction (XRD) was used to estimate the magnitude of residual stresses on the surface of the specimens. Compressive residual stresses at the surface and sub-surface of about −700 MPa were obtained.

Improvement of Method and Mechanism for Conical and Paraboloid Springs Hardening

2021 ◽  
Vol 1037 ◽  
pp. 227-232
Author(s):  
Nikita A. Zemlyanushnov ◽  
Nadezhda Y. Zemlyanushnova
Keyword(s):  
New Method ◽  
Cylindrical Shape ◽  
Plastic Deformations ◽  
Conical Shape ◽  
Inner Surface ◽  
Hardening Mechanisms ◽  
The Difference ◽  
Compression Springs

The disadvantage of the known methods of hardening springs is the impossibility of their use when hardening springs of a conical shape or of a shape of a paraboloid of rotation, since they are intended only for cylindrical shape springs and are not suitable for conical shape springs or those of a shape of a paraboloid of rotation specifically because of the difference in the shape of the springs. One of the disadvantages of the known springs hardening mechanisms is the impossibility of hardening the inner surface of the conical compression springs. A new method of hardening springs is proposed, the unmatched advantage of which is the ability to create plastic deformations on the inner and outer surfaces of the spring coils compressed to contact and on the surfaces along the line of contact between the coils. A new advantageous mechanism for hardening springs is proposed, which makes it possible to harden the inner surface of compression springs having a conical shape or a paraboloid shape of rotation, in a compressed state.

Surging in Helical Valve Springs

1933 ◽  
Vol 37 (271) ◽  
pp. 641-654
Author(s):  
J. Dick
Keyword(s):  
Internal Combustion Engine ◽  
High Speed ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Helical Spring ◽  
Dynamic Effects ◽  
Helical Springs ◽  
Air Resistance ◽  
Speed Of Propagation

The high-speed internal combustion engine presents many problems arising from dynamic effects. Amongst these is the phenomenon known as “ surging ” in the helical springs used for the operation of the valves.If a helical spring is held at both ends, any disturbance in the spring passes up and down as a wave, being reflected at each end in turn. This to and fro movement continues until it is damped out by friction and air resistance. With most springs the speed of propagation of the disturbance is considerable and only a confused flutter of the coils is apparent to an observer. A disturbance of this type is caused by any movement of the end of the spring. The more abrupt the movement of the end, the more pronounced will the disturbance be. An instance of the type of movement producing a pronounced surge is that due to impact between the tappet and the valve when the valve commences to open.

scholarly journals Localized electrodeposition micro additive manufacturing of pure copper microstructures

2021 ◽  
Author(s):  
Wanfei Ren ◽  
Jinkai Xu ◽  
Zhongxu Lian ◽  
Xiaoqing Sun ◽  
Zheming Xu ◽  
...  
Keyword(s):  
Additive Manufacturing ◽  
Electrochemical Deposition ◽  
Closed Loop ◽  
Pure Copper ◽  
Closed Loop Control ◽  
Helical Spring ◽  
Loop Control ◽  
Helical Springs ◽  
Atomic Force ◽  
Microscopic Morphology

Abstract The fabrication of pure copper microstructures with submicron resolution has found a host of applications such as 5G communications and highly sensitive detection. The tiny and complex features of these structures can enhance device performance during high-frequency operation. However, the easy manufacturing of microstructures is still a challenge. In this paper, we present localized electrochemical deposition micro additive manufacturing (LECD-μAM), combining localized electrochemical deposition (LECD) and closed-loop control of atomic force servo technology, which can print helical springs and hollow tubes very effectively. We further demonstrate an overall model based on pulsed microfluidics from a hollow cantilever LECD process and the closed-loop control of an atomic force servo. The printing state of the micro-helical springs could be assessed by simultaneously detecting the Z-axis displacement and the deflection of the atomic force probe (AFP) cantilever. The results showed that it took 361 s to print a helical spring with a wire length of 320.11 μm at a deposition rate of 0.887 μm/s, which could be changed on the fly by simply tuning the extrusion pressure and the applied voltage. Moreover, the in situ nanoindenter was used to measure the compressive mechanical properties of the helical spring. The shear modulus of the helical spring material was about 60.8 GPa, much higher than that of bulk copper (~44.2 GPa). Additionally, the microscopic morphology and chemical composition of the spring were characterized. These results delineated a new way of fabricating terahertz transmitter components and micro-helical antennas with LECD-μAM technology.

Optimized Thermomechanical Treatment for Strong and Ductile Martensitic Steels

2007 ◽  
Vol 539-543 ◽  
pp. 4526-4531 ◽  
Author(s):  
Araz Ardehali Barani ◽  
Dirk Ponge
Keyword(s):  
Heat Treatment ◽  
Thermomechanical Treatment ◽  
Spring Steel ◽  
Martensitic Steels ◽  
Medium Carbon ◽  
Heat Treated ◽  
Conventional Heat Treatment ◽  
The Matrix ◽  
Different Levels ◽  
Strength And Ductility

In this study the effect of thermomechanical treatment on the microstructure of austenite and martensite and the mechanical properties of a medium carbon silicon chromium spring steel with different levels of impurities is investigated. Results are presented for conventional heat treatment and for thermomechanical treatment (TMT). Compared to conventionally heat treated samples austenite deformation improves strength and ductility. Thermomechanically treated samples are not prone to embrittlement by phosphorous. TMT influences the shape and distribution of carbides within the matrix and at prior austenite grain boundaries. It is shown that utilization of TMT is beneficial for increasing the ultimate tensile strength to levels above 2200 MPa and at the same time maintaining the ductility obtained at strength levels of 1500 MPa by conventional heat treatment. The endurance limit is increased and embrittlement does not occur.

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