Continuous as Against Intermittent Fling-Off Cooling of Gear Teeth

1974 ◽  
Vol 96 (4) ◽  
pp. 529-538 ◽  
Author(s):  
G. J. J. van Heijningen ◽  
H. Blok
Keyword(s):  
Experimental Data ◽  
Continuous Method ◽  
Main Subject ◽  
Gear Teeth ◽  
Naturally Occurring ◽  
Cooling Method ◽  
Oil Mist ◽  
Gear Oil ◽  
Design Calculations

The main subject of the present paper is the still relatively unknown fling-off cooling method through continuous supply of the gear oil to the roots of the tooth faces to be cooled, for instance through holes connecting with a manifold inside the tooth rim. The cooling potentialities of this continuous method are compared with those of the naturally occurring “intermittent” fling-off cooling treated previously by A. de Winter and H. Blok [1]. A third fling-off cooling method is again continuous but, in contrast to that by root supply, occurs naturally in that it is brought about by the impingement of comparatively cool droplets from the oil mist in the gear casing. This method will be treated only cursorily, lacking certain experimental data to be substituted in design calculations based on the pertinent theoretical relationships.

Finite Element Analysis-Based Thermo-Mechanical Performance Study of Heavy Vehicle Medium Duty Transmission Gearbox

2021 ◽  
pp. 322-336
Author(s):  
Ashwani Kumar ◽  
Yatika Gori ◽  
Pravin P. Patil
Keyword(s):  
High Performance ◽  
Mechanical Performance ◽  
Elastohydrodynamic Lubrication ◽  
Gear Train ◽  
Performance Study ◽  
Element Analysis ◽  
Gear Teeth ◽  
Oil Mist ◽  
Gear Oil ◽  
Reverse Gear

The main objective of this chapter is to investigate the performance of automobile transmission gearbox under the influence of load, rotational speed, and lubrication on multi speed gearbox gear surface. Gear oil SAE 80W-90 was used as gearbox lubricant, for cooling of transmission gearbox for high performance. An assumption has been made at the air-gear oil mist within transmission is under steady state condition, in isothermal equilibrium with the transmission gear oil bath of lubricant. The lubrication in multi speed transmission is subjected to thermo-elastohydrodynamic lubrication. The present chapter deals with the thermo-mechanical performance study of multi speed transmission (4 speed, excluding reverse gear) system, which combines transient structure analysis of the gear train assembly. The engaged gear teeth pairs transmit torque subjected to thermo-elastohydrodynamic arrangements of lubrication. The study here analyzed transmission in second gear pair.

scholarly journals Conifers Phytochemicals: A Valuable Forest with Therapeutic Potential

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 3005
Author(s):  
Kanchan Bhardwaj ◽  
Ana Sanches Silva ◽  
Maria Atanassova ◽  
Rohit Sharma ◽  
Eugenie Nepovimova ◽  
...  
Keyword(s):  
Experimental Data ◽  
Potential Role ◽  
Therapeutic Potential ◽  
Fungal Infections ◽  
Cell Damage ◽  
Cancer Growth ◽  
Naturally Occurring ◽  
Antioxidant Effects

Conifers have long been recognized for their therapeutic potential in different disorders. Alkaloids, terpenes and polyphenols are the most abundant naturally occurring phytochemicals in these plants. Here, we provide an overview of the phytochemistry and related commercial products obtained from conifers. The pharmacological actions of different phytochemicals present in conifers against bacterial and fungal infections, cancer, diabetes and cardiovascular diseases are also reviewed. Data obtained from experimental and clinical studies performed to date clearly underline that such compounds exert promising antioxidant effects, being able to inhibit cell damage, cancer growth, inflammation and the onset of neurodegenerative diseases. Therefore, an attempt has been made with the intent to highlight the importance of conifer-derived extracts for pharmacological purposes, with the support of relevant in vitro and in vivo experimental data. In short, this review comprehends the information published to date related to conifers’ phytochemicals and illustrates their potential role as drugs.

The Compliance of Solid, Wide-Faced Spur Gears

1990 ◽  
Vol 112 (4) ◽  
pp. 590-595 ◽  
Author(s):  
J. H. Steward
Keyword(s):  
Experimental Data ◽  
Contact Line ◽  
Load Distribution ◽  
3D Model ◽  
Spur Gear ◽  
Point Load ◽  
Spur Gears ◽  
Line Load ◽  
Gear Teeth ◽  
Theoretical Results

In this paper, the requirements for an accurate 3D model of the tooth contact-line load distribution in real spur gears are summarized. The theoretical results (obtained by F.E.M.) for the point load compliance of wide-faced spur gear teeth are set out. These values compare well with experimental data obtained from tests on a large spur gear (18 mm module, 18 teeth).

scholarly journals The Effect of a Gear Oil on Abrasion, Scuffing, and Pitting of the DLC-Coated 18CrNiMo7-6 Steel

Coatings ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 2 ◽  
Author(s):  
Remigiusz Michalczewski ◽  
Marek Kalbarczyk ◽  
Anita Mańkowska-Snopczyńska ◽  
Edyta Osuch-Słomka ◽  
Witold Piekoszewski ◽  
...  
Keyword(s):  
Simple Model ◽  
Mineral Oil ◽  
Hardened Steel ◽  
Crn Coating ◽  
Gear Teeth ◽  
Hard Particles ◽  
Polyalkylene Glycol ◽  
Gear Oil ◽  
Gear Oils ◽  
Harsh Conditions

The transmissions of mining conveyors are exposed to very harsh conditions. These are primarily related to the contamination of the gear oil with hard particles coming from coal and lignite, which can cause intensive abrasive wear, scuffing, and even pitting, limiting the life of gears. One of the ways to prevent this problem is the deposition of a wear-resistant coating onto gear teeth. However, a proper choice of gear oil is an important issue. The abrasion, scuffing, and pitting tests were performed using simple, model specimens. A pin and vee block tester was employed for research on abrasion and scuffing. To test pitting, a modified four-ball pitting tester was used, where the top ball was replaced with a cone. The test pins, vee blocks, and cones were made of 18CrNiMo7-6 case-hardened steel. A new W-DLC/CrN coating was tested. It was deposited on the vee blocks and cones. For lubrication, three commercial industrial gear oils were used: A mineral oil, and two synthetic ones with polyalphaolefin (PAO) or polyalkylene glycol (PAG) bases. The results show that, to minimize the tendency forabrasion, scuffing, and pitting, the (W-DLC/CrN)-8CrNiMo7-6 tribosystems should be lubricated by the PAO gear oil.

Design Calculations on the Recycle of Malysite in Sludge under the Synergistic Effect of Acidification and Ultrasonic

2011 ◽  
Vol 204-210 ◽  
pp. 796-801
Author(s):  
Bo Zhou ◽  
Nai Rui Liu ◽  
Lei Lei Mi
Keyword(s):  
Experimental Data ◽  
Synergistic Effect ◽  
Design Process ◽  
Design Criterion ◽  
Design Flow ◽  
Treatment Unit ◽  
Unit Design ◽  
Filtration Unit ◽  
Design Calculations ◽  
Quality Material

During the recycle process of malysite in sludge under the synergistic effect of acidification and ultrasonic, the features of malysite, the principles and steps of design calculations for sludge malysite are introduced on the basis of the previous experimental data. According to the function, the design process can be classified into pretreatment unit, coagulation treatment unit, malysite recovery unit, sedimentation and filtration unit. Design calculations are conducted in the light of the requirements on design flow, cycle time, influent water quality, material and experimental data. Design calculations and selections as well as device construction are accomplished based on the design criterion of water treatment. Ultimately, the parameters of each treatment unit responding to the design process are obtained through the experimental validation by means of the constructed experimental device.

Relationship between growth rate and undercooling in Pt-added Y1Ba2Cu3O7−x

1996 ◽  
Vol 11 (5) ◽  
pp. 1114-1119 ◽  
Author(s):  
A. Endo ◽  
H. S. Chauhan ◽  
Y. Nakamura ◽  
Y. Shiohara
Keyword(s):  
Experimental Data ◽  
Growth Rate ◽  
Parabolic Equation ◽  
Growth Rates ◽  
Crystal Size ◽  
Experimental Conditions ◽  
Seed Crystals ◽  
Cooling Method ◽  
Increasing Trend ◽  
Good Agreement

Y1Ba2Cu307−x (Y123) crystals were grown by two different methods, the constant undercooling solidification and the continual cooling method, with top seeding by Sm123 seed crystals in order to investigate a relationship between undercooling (ΔT) and a growth rate (R). The crystals of Y123 with a sharp faceted interface, which consisted of {100} and {001} faces, grew epitaxially from the seed. It was found that the growth rates of {100} face (Ra) and that of {001} face (Rc) showed an increasing trend with increasing ΔT, and Rc was faster than Ra within these experimental conditions, ΔT < 20 K. The relation between R and ΔT follows the parabolic equation, viz. Ra ∝ ΔT1.9 and Rc ∝ ΔT1.3 for {100} and {001} faces, respectively. The simulated crystal size using the R and ΔT relations obtained from the constant undercooling method showed good agreement with experimental data by the continual cooling.

scholarly journals Abrasive Wear, Scuffing and Rolling Contact Fatigue of DLC-Coated 18CrNiMo7-6 Steel Lubricated by a Pure and Contaminated Gear Oil

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7086
Author(s):  
Waldemar Tuszyński ◽  
Remigiusz Michalczewski ◽  
Edyta Osuch-Słomka ◽  
Andrzej Snarski-Adamski ◽  
Marek Kalbarczyk ◽  
...  
Keyword(s):  
Abrasive Wear ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Solid Particles ◽  
Rolling Contact ◽  
Lubricating Oil ◽  
Gear Teeth ◽  
Ball Rolling ◽  
Gear Oil ◽  
Gear Oils

Due to extreme working conditions of mining conveyors, which contaminate gear oil with solid particles, their transmissions are exposed to intensive abrasion, scuffing, and even rolling contact fatigue (pitting). These effects shorten gear life. To prevent their occurrence, a wear-resistant coating can be deposited on gear teeth. The resistance to abrasive wear, scuffing, and pitting was investigated and reported in the article. Simple, model specimens were used. Abrasive wear and scuffing were tested using a pin-and-vee-block tribosystem in sliding contact. A cone–three-ball rolling tribosystem was employed to test pitting. The material of the test specimens (pins, vee blocks, cones) was 18CrNiMo7-6 case-hardened steel. Two types of DLC (Diamond-like Coatings) coatings were tested, W-DLC and W-DLC/CrN. The vee blocks and cones were coated. Two industrial gear oils were selected to lubricate the specimens: one with a mineral and one with a synthetic PAO (polyalphaolephine) base, as pure oil or contaminated with solid particles from a coal mine. The results show that, to minimize the tendency to abrasion, scuffing, and pitting of specimens made of 18CrNiMo7-6 steel, the W-DLC/CrN coating should be deposited. This coating also gives very good protection when the lubricating oil is contaminated.

Hornblende—anthophyllite and hornblende—cummingtonite parageneses

1970 ◽  
Vol 37 (292) ◽  
pp. 923-928 ◽  
Author(s):  
A. Choudhuri
Keyword(s):  
Experimental Data ◽  
Naturally Occurring

SummaryThe associations hornblende and anthophyllite or cummingtonite are dealt with briefly in the light of experimental data and naturally occurring assemblages. On the basis of the distribution of Mg and Fe2+ in coexisting amphiboles and on the calculated and experimental slopes of a reaction in which the amphiboles hornblende and anthophyllite are formed a tentative P-T-x diagram is suggested for these parageneses.

Fling-Off Cooling of Gear Teeth

1974 ◽  
Vol 96 (1) ◽  
pp. 60-70 ◽  
Author(s):  
A. DeWinter ◽  
H. Blok
Keyword(s):  
Frictional Heat ◽  
Heavy Duty ◽  
Gear Teeth ◽  
Gear Oil

An exploratory theory shows even moderate rates of supply of the gear oil to the tooth faces to suffice for attaining the limiting coolant capacity that proves to be inherent in the conventional centrifugal fling-off process. However, in heavy-duty gears beyond a certain size and speed the conventional “intermittent” fling-off cooling can no longer take a substantial share in the withdrawal of the frictional heat generated in the meshing zone. Much greater cooling capacities are then realizable by the less known “continuous” fling-off process, to be dealt with in a followup paper.

The Scuffing Resistance of WC/C Coated Spiral Bevel Gears

2014 ◽  
Vol 604 ◽  
pp. 36-40 ◽  
Author(s):  
Remigiusz Michalczewski ◽  
Marek Kalbarczyk ◽  
Waldemar Tuszynski ◽  
Marian Szczerek
Keyword(s):  
Bevel Gear ◽  
Spiral Bevel Gear ◽  
Test Rig ◽  
Low Friction ◽  
Spiral Bevel Gears ◽  
Gear Teeth ◽  
Bevel Gears ◽  
Trade Name ◽  
Gear Oil ◽  
Spiral Bevel

One of the main problems with the operation of spiral bevel gears is related to very severe conditions in the contact of the meshing teeth; therefore, lubrication is very difficult, which increases the risk of scuffing occurrence. One of the ways to achieve better scuffing resistance is by the deposition of a low-friction coating on the bevel gears teeth. Gear scuffing tests were performed using a bevel gear test rig designed and manufactured at ITeE-PIB. The authorial bevel gear scuffing test was performed. Specially designed, spiral bevel gears were used for testing. Two material combinations were tested: uncoated pinion - coated wheel and, for reference, both gears without coatings. The a-C:H:W (trade name WC/C) coating of DLC type was deposited on the wheel teeth. A mineral, automotive gear oil of API GL-5 performance level was used for lubrication. It is shown that the resistance to scuffing may be significantly improved when the a-C:H:W coating is deposited on the spiral bevel gear teeth.

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