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1

Odlewanie tłoków do silników spalinowych ze stopów aluminium na przestrzeni 50 lat doświadczenia Federal-Mogul Gorzyce

Piątkowski Jarosław, Krępa Adam

Przegląd Odlewnictwa

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2023

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Vol. 73, nr 3-4

84--85

PL

W artykule przedstawiono rys historyczny odlewania tłoków silników spalinowych na przykładzie 50. lat doświadczenia Federal-Mogul (FM) Gorzyce sp. z o.o. Zwrócono szczególną uwagę na zmiany w konstrukcji układu chłodzenia kokilarek, które obecnie są sprzężone z robotami zalewającymi ciekły stop tłokowy Al-SiCu-Ni-Mg. To rozwiązanie zapewnia równomierną krystalizację tłoków i optymalną wydajność procesu ich odlewania. Na skutek konieczności poprawy sprawności silnika, a tym samym zmniejszenia zużycia paliwa i emisji substancji szkodliwych dla środowiska, zmianie uległa również budowa tłoków. W zależności od rodzaju silnika, obecne tłoki posiadają różny kształt denka, którego krawędzie są przetapiane laserowo, niższą tzw. „koronę” tłoka i odchudzone ścianki wewnętrzne. Dla zapewnienia mniejszych strat tarcia układu: tłok-pierścienie-cylinder i wzmożonego chłodzenia części pierścieniowej, nowoczesne tłoki są wyposażone w komponenty (kanały solne, alfinowane wkładki pierścieniowe), a płaszcz tłoka jest poddawany zabiegom obróbki powierzchniowej. Stosowanie innowacyjnych rozwiązań w Federal-Mogul Gorzyce Sp. z o.o. zapewnia uzyskanie kompromisu pomiędzy produkcją silników o zmniejszonej pojemności skokowej i dużej mocy, przy jednoczesnym zachowaniu trwałości i niezawodności odlewanych dziś tłoków ze stopów aluminium.

EN

The article presents a historical overview of the casting of combustion engine pistons on the example of 50 years of experience of Federal-Mogul (FM) Gorzyce Ltd. Particular attention was paid to the changes in the design of the cooling system of the mold making machines, which are currently coupled with robots pouring liquid Al-Si-Cu-Ni-Mg piston alloy. This solution ensures uniform crystallization of the pistons and optimal efficiency of the casting process. As a result of the need to improve engine efficiency, and thus reduce fuel consumption and emissions of substances harmful to the environment, the design of the pistons has also changed. Depending on the type of engine, the current pistons have a different shape of the bottom, the edges of which are melted by laser, the lower, so-called „crown” of the piston and slimmed down inner walls. To ensure lower friction losses of the piston-rings-cylinder system and increased cooling of the annular part, modern pistons are equipped with various components (salt channels, and alfinated ring inserts), and the piston skirt is subjected to surface treatment. The use of innovative solutions at Federal-Mogul Gorzyce Ltd provides a compromise between the production of engines with reduced displacement and high power, while maintaining the durability and reliability of today’s cast aluminum alloy pistons.

2

Optimization of the combustion chamber strength of aluminum pistons in diesel engines using the DuralBowl technology

Żurawski Paweł

Combustion Engines

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2023

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R. 62, nr 1

91--96

EN

The article focuses on the problem of loading the combustion chamber of diesel engine pistons together with the method of its optimization using the DuralBowl technology. Along with the growing requirements of exhaust emission standards, the increasing competition in the efficiency of internal combustion engines, the load on the combustion pistons increases due to the increase in pressure and temperature of fuel combustion and the tendency to slim the structure. Numerical analyzes and analyzes of damaged pistons in diesel engines have shown that one of the places most exposed to piston damage are the combustion chambers. There is a concentration of thermomechanical stress at the edge of the combustion chamber, which may lead to the destruction of the piston and the necessity to carry out overhaul of the drive unit. One of the technologies that optimizes the strength of this zone is the DuralBowl local remelting process. This process allows for several timesimprovement in the fatigue strength of pistons in internal combustion engines. The article analyzes the thermomechanical load on the combustion chamber along with the impact of this load on the durability of pistons in diesel engines. An analysis of the DuralBowl process was also performed, aimed at eliminating the negative effects of loading the combustion chamber, extending the piston life. The analysis focused on the microstructure of the material before and after the DuralBowl process.

3

Development of measurement apparatus of piston assembly friction in a small motorcycle engine

Nakashima Kohei, Matsunaga Kota, Uchiyama Yosuke, Yoshida Masao

Combustion Engines

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2023

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R. 62, nr 3

32--37

EN

This study developed a friction measurement apparatus with a floating cylinder liner in a small motorcycle engine. In this measurement apparatus, joint plates were installed in the grooves on the outer periphery of the floating liner, and then the plates, as well as load washers of piezo type, were mounted in the cylinder block at both the thrust and the anti-thrust sides. A stepped ring, protruding inward, was mounted on the top of the floating liner so that cylinder pressure acting on the stepped portion was balanced in the vertical direction. Thus, it was possible to measure the friction in the sliding directions of the piston. Using this apparatus, the effect of the engine operating period on friction was investigated in a piston micro-dimpled with a fine particle bombarding process. Results indicated that, at low engine speeds, friction decreased with the operating period, but at high engine speeds, friction decreased after 10 hours of operation, and then increased after 20 hours of operation.

4

Influence of piston surface treatment on piston assembly friction in an eco-mileage vehicle engine

Nakashima Kohei, Uchiyama Yosuke

Combustion Engines

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2022

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R. 61, nr 1

18--23

EN

This study investigated the effect on piston assembly friction after treating piston surfaces with a fine particle bombarding process, using a friction measurement apparatus with a floating cylinder liner, similar to an eco-mileage vehicle engine. Friction was measured in four conditions: (1) no treatment (standard piston in a commercially-available engine), (2) micro dimple treatment (45 μm ceramic particles were air-blasted onto the piston surface), (3) molybdenum disulfide (MoS2) shot treatment (1 μm MoS2 particles were air-blasted onto the piston surface), and (4) combination of the previous two micro dimple and MoS2 shot treatments (first 45 μm ceramic particles and then 1 μm MoS2 were air-blasted onto the piston surface). Results indicated that friction decreased in the following order: no treatment > micro dimple treatment > MoS2 shot treatment > combination of micro dimple and MoS2 shot treatments.

5

Analysis of hydraulic system for adjustable ground clearance mechanism

Chada Jithendra Sai Raja, Sandeep Venkat G., Chollangi Rajesh

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 3

203--208

EN

The stability of a vehicle depends on many parameters. The Centre of Gravity is one of the most important in them. If the height of center of gravity from the ground decreases the stability of the vehicle increases. But when the ground clearance is too low it has a chance of collision vehicle and the ground while going on an uneven road or with speed brakes. So, to avoid the collision of a vehicle to ground and increase the stability a mechanism to adjust the ground clearance is to be attached. Also, the lift and drag forces can also be altered using this adjustable ground clearance mechanism. The designers usually fix ground clearance and they try to acquire this by the suspension system. The suspension system has tires, tire air, springs, shock absorber, and other parts to connect the vehicle with the wheels. The present paper describes the significance of using hydraulic oil as a working fluid in an adjustable ground clearance mechanism. Also describes the design and analysis of piston and cylinder rod.

6

Mechanical and Thermal Stresses in an HPDC Machine Plunger During the Dosing and Filling Process

Jankowski Jacek, Kołakowski Dariusz, Pisarek Bogusław Piotr

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 2

1--12

EN

Distributions of mechanical and thermal stresses in a plunger of the high pressure die casting machine with a horizontal shot sleeve have been considered for a flat thermal stationary problem. An axial pressure of the plunger pressing in the technological process has been accounted for as well. Principal and equivalent stresses have been determined within two different hypotheses on the strength of materials, including one theory covering various allowable stresses in tension and compression. Four plunger material variants have been analysed.

7

Analysis of Mechanical and Thermal Stresses in a Pressure Casting Machine Plunger

Jankowski Jacek, Kołakowski Dariusz, Pisarek Bogusław Piotr

Advances in Science and Technology. Research Journal

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2020

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Vol. 14, no 1

209--223

EN

The study discusses the thermo‑mechanical stress distribution in the plunger of a cold chamber casting machine with a horizontal casting chamber in the stationary aspect. The main stresses as well as the reduced stresses were determined for four different strength hypotheses, two of which took into account different acceptable maximal tensile and compressive stresses. For comparative purposes, the calculations were performed for three different construction materials used for cold chamber pressure machine plungers: grey pearlitic cast iron, high silicon bronze and beryllium bronze, as well as one more type of bronze, which has not been used for plungers so far, i.e. aluminium‑iron‑nickel bronze, constituting the initial alloy for the newly‑developed complex bronzes with high wear resistance and elevated strength.

8

The numerical calculation module for piston rings & cylinder and research with analysis of the results of the internal combustion engine locomotive during the 85-hour endurance test

Kaźmierczak Andrzej, Borkowska Joanna, Tkaczyk Marcin

Pojazdy Szynowe

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2019

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Nr 3

24--34

EN

The piston with piston rings and bearing surface is a self-contained and highly complex tribological system. One of the most widespread global friction pairs traversed by reciprocating a pair of piston rings - cylinder internal combustion engine. Group PRC combustion engine is the solution generating considerable friction. Various researchers estimate the share of friction losses, per node piston rings - cylinder liner, at 19 to 60% of the total friction losses in the combustion engine. This paper describes part of a larger program to reduce wear the set working parts (piston, piston ring and bearing surface). The project is implemented through the development of new designs of piston rings with anti-wear coating that contains synthetic diamond in the form of loose embedded in a coating of chromium (PRC). The aim of the author was to present the methodology used to compute characterized by a particular procedure. In practical use FEM software is used and the FVM. Developed and implemented Piston Rings Calculation Module is compatible with the idea of numerical computational methods is to say: functionally consists in carrying out a calculation of the desire to achieve the exact solution (the nearest is real) by conducting and receiving intermediate solutions (the next).

PL

Tłok wraz z pierścieniami oraz powierzchnią cylindra jest bardzo złożonym zamkniętym systemem trybologicznym. Pierścienie tłoka – cylinder jest jedną z najbardziej globalnie rozpowszechnionych par tarcia silników spalinowych. Para tarcia TPC jest rozwiązaniem wytwarzającym znaczące tarcie w silnikach spalinowych. Różne źródła naukowe określają straty na jeden węzeł spowodowane tarciem pary pierścień-ściana cylindra jako 19 do 60% wartości wszystkich strat tarcia w silniku spalinowym. W tym artykule omówiono część większego programu badawczego mającego na celu zmniejszenie zużycia pracujących elementów (tłok, pierścienie tłoka, powierzchnia cylindra). Projekt ten jest wdrażany w ramach rozwoju nowych konstrukcji pierścieni tłokowych z powłoką zapobiegającą zużyciu, zawierającą syntetyczny diament luźno zatopiony w powłoce chromu (TPC). Celem Autorów było przedstawienie metodologii stosowanej do obliczeń charakteryzującej się określoną procedurą. W praktyce wykorzystuje się oprogramowanie MES oraz MOS. Opracowany i wdrożony moduł obliczeniowy pierścieni tłokowych jest zgodny z ideą numerycznych metod obliczeniowych, to znaczy: funkcjonalnie polega na przeprowadzeniu obliczenia zamiaru uzyskania dokładnego wyniku (najbardziej zbliżonego rzeczywistości) poprzez uzyskanie i wykorzystanie wartości pośrednich.

9

Finite element analysis of a composite piston for a diesel aircraft engine

Pietrykowski Konrad, Magryta Paweł, Skiba Krzysztof

Combustion Engines

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2019

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R. 58, nr 4

107--111

EN

The article presents calculations of thermal and mechanical loads of the piston, consisting of two parts: steel and aluminum. The calculations were made using FEM in the Abaqus software. The piston is characterized by a split construction and was equipped with a cooling oil channel. The piston will be used in an aircraft diesel engine characterized by opposite piston movement. The presented geometry of the piston is the next of the ones being developed earlier and contains preliminary assumptions as to the size and main geometrical dimensions. The thermal boundary conditions of the simulation tests assumed defined areas of heat reception surface and heating of the piston by defining a temperature map on its crown. The results of these studies were presented in the form of temperature distribution and heat flux on the surface of the tested element. The strength boundary conditions assumed a mechanical load in the form of pressure resulting from the pressure in the combustion chamber applied to the piston crown surface and the opposite pressure defined on the support at the surface of contact between the piston and the piston pin. The results of these tests were presented in the form of stress distribution on the surface of the tested element. As a result of the analyses carried out, the results constituting the basis for further modernization of the piston geometry were obtained.

10

Cordunum pistons increase diesel engine economy and reliability

Marchenko Andriy, Shpakovskyy Volodymyr, Volikov Volodymyr

Acta Innovations

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2019

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no. 33

28--37

EN

Taking into account the oil resources depletion the requirements to fuel consumption of internal combustion engines are now increasing as well as to their reliability and durability. With the continual increase in the number of internal combustion engines in operation, along with the problem of parts of the cylinder piston group wearing out has caused exhaust from such engines to be one of the main source of harmful pollutant emissions in cities. Therefore, environmental requirements have in turn increased dramatically. The engine resource and its efficiency largely depend on the process of fuel combustion in the combustion chamber. Experimental studies aimed to improve the working process on diesel engines by piston insulation have shown an effective decrease in fuel consumption by reducing heat loss and more complete fuel combustion. When oxide ceramic coatings were used on the piston and cylinder head, the maximum power increased and the specific fuel consumption decreased. However ceramic coatings are not widely used due to their peeling. We have developed a technology for the galvanic plasma treatment of pistons, which made it possible to obtain on the pistons surface made of aluminum alloys a ceramic corundum layer with high adhesion to the base metal that does not peel and has electret properties. In 1993, pistons with a corundum surface layer were installed in a shunting diesel locomotive and life-time running tests were conducted. Such pistons increased wear resistance, reduced the wear of cylinder liners, increased the strength of the annular jumpers, and were not prone to burnouts and scuffing. They provided an increase in the resource of the cylinder-piston group of the diesel engine by more than 125 thousand engine hours. The paper provides an analysis of the effect of corundum pistons thermal insulation on significant increasing the, engine power and fuel consumption reduction. Basing on experimental bench studies of a gasoline engine, a tractor diesel engine and long-term operational life tests of diesel engines, an attempt had been made to explain the reasons for the improvement in the engines’ efficiency.

11

Friction reducing performance of carbon nanotubes covered pistons in internal combustion engines – engine test results

Kałużny J., Merkisz J., Kempa K., Gapiński B., Wróblewski E., Stepanenko A., Al-Karawi M.

Combustion Engines

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2018

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R. 57, nr 1

14--24

EN

This article discusses the posibility of reducing friction losses in internal combustion engines by using carbon nanotubes, pointing out the large potential of this application. Experimental pistons were made of standard aluminum alloy and coated with a layer of nanotube deposits by spraying them with an aqueous solution containing the binder. The proposed technology of applying layers of nanotubes can be adopted in industrial-scale production. Engine tests were carried out showing a significant reduction of the engine motoring torque, up to 16% for the experimental pistons, thus confirming the favorable tribological properties of nanotubes observed in tribological research and reported by many authors. Supplementary tests were carried out: SEM, EDS, coordinate measuring technique, and x-ray tomography. An alternative technology for hierarchical nanotube multilayer coatings electro-deposition was proposed.

12

Influence of stepped piston bearing surface on friction loss in rail combustion engine

Finke S., Wróblewski E.

Journal of Mechanical and Transport Engineering

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2017

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Vol. 69, No. 3

15--20

EN

In designing railway combustion engines, the key objective is to reduce fuel consumption. The way to achieve this objective is reduction of friction losses in the piston – cylinder node, which is the main in combustion engine. The analysis subjected railway engine DZC6 produce by Anglo Belgian Corporation, where on the basis of the parameters was carried out simulations for pistons with revised microgeometry bearing surface.

PL

W projektowaniu współczesnych kolejowych silników spalinowych, kluczowym warunkiem jest uzyskanie niskiego zużycia paliwa. Drogą do spełnienia tego założenia jest redukcja strat tarcia w węźle tłok–cylinder, który stanowi główny węzeł silnika spalinowego. W artykule, analizie poddany został zmodyfikowany tłok ze zmienioną mikrogeometrią powierzchni nośnej, pochodzący z silnika kolejowego DZC6 produkcji Anglo Belgian Corporation, gdzie na podstawie jego parametrów pracy przeprowadzono symulacje strat tarcia.

13

Zwiększenie podatności stojaków obudowy zmechanizowanej jako remedium na zjawiska gwałtownych osunięć stropu

Marianowski J.

Inżynieria Górnicza

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2017

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nr 1-2

30--35

PL

Przedstawiono istotę wykorzystania obszaru pod tłokiem rdzennika II stopnia siłownika teleskopowego do ochrony obudowy zmechanizowanej przed nadmiernymi i gwałtownymi osunięciami stropu. Zaproponowano umieszczenie zaworu upustowego na tłoczysku rdzennika wewnętrznego stojaka. Wykonane prototypowe egzemplarze zaworów poddano weryfikacji doświadczalnej na stacji prób. Rezultaty pomiarów przedstawiono graficznie na wykresach.

EN

The article presents the essence of the utilization of the inner space under the piston of the second-grade pit prop of a telescope cylinder in order to protect a power roof support against excessive and rapid roof failures. The placement of the blow off valve on the pit prop piston rod of the inner cylinder has been proposed. Prototype specimen of valves have been subjected to experimental verification at a testing station. The results of the measurements have been shown in diagrams.

14

Test bench measurement of friction loss in combustion engine

Wróblewski E., Finke S.

Combustion Engines

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2017

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R. 56, nr 1

46--50

EN

The results of modeling and bench testing friction losses in the main engine kinematic nodes for different lubricating oil temperature values was presented in the article. The study was performed to evaluate the effect of lubricating oil temperature on the engine friction losses. In addition to friction losses in the crankshaft bearings and the piston rings in a cylinder-piston group the friction loss due to charge exchange in the cylinder, drive of timing system and the oil pump were measured. The obtained results show the course of the friction loss in the combustion engine. The research shows that the thermal state of the engine lubricating oil has effect on the amount of friction losses. Formulated conclusions allow to assess the impact of the oil temperature on the friction losses in the main friction nodes in combustion engine.

15

Studying a construction of pistons for the aircraft CI engine

Siadkowska K., Majczak A., Barański G.

Combustion Engines

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2017

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R. 56, nr 1

161--167

EN

This paper examines the selected constructions of piston for aircraft CI engines and discusses tendencies in a development of piston designs. The paper addresses the question of using new materials and coatings to improve quality of pistons and the study of heat transfer and methods to absorb heat from a piston by means of cooling ducts. The selected materials were examined in terms of their advantages and drawbacks. The paper discusses different shapes of piston heads and their impact on combustion as well as indicates other factors behind parameters of combustion and toxic emission like injector shape types, lubrication types and clearances in the combustion chamber.

16

Research and analysis of the results from the tribotester test for piston

Borkowska J., Kaźmierczak A.

Combustion Engines

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2017

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R. 56, nr 2

14--17

EN

Piston – ring – cylinder assembly of combustion engine has a lot of friction pairs examples, also one of them which decide about fastness to wear, it means first sealing ring – cylinder, called further very simply ring – cylinder unit. During work of this unit we can observe wear of piston, precisely – of coating which is deposited on ring to prolong service life. Objective of this work was to realize a test of roll-block type on tribotester to set durability of piston sample. Within the framework of this test were investigated a prototyped piston’s rings with diamond embankment. Piston rings are made of diamond coating technology with a porous chromium coating, where in pores is deposited on said diamond powder with a grain size about 1 micron. The work will be carried out of an analysis of collaboration piston – rings – cylinder unit in internal combustion engine and an analysis of the use of hard materials in friction pairs, including powders. The work aims to show the possibilities and benefits of the application of new protective coatings to reduce their wearing, which is consistent with the observed trend of technology development.

17

Simulation and bench studies of the constructively and technologically modernized high performance piston aircraft engine. Stage I

Ostapski W., Wierzchoń T., Rudnicki J., Dowkontt S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 1

93--105

EN

The paper presents an analysis of tribological wear of an assembly composed of cylinder liner and piston rings in a piston aircraft engine. In place of the previously used technology of gas nitriding of the cylinder liner (made out of 38CrAlMo6‒10 steel), formation of multi-component or composite layers by nitriding in plasma discharge environment was proposed. Also, a modification of the previously used chromium coating of the piston rings by plasma nitriding was proposed. A study on the structure and properties of surface layer diffusion manufactured by utilizing the phenomenon of cathode sputtering was carried out. Wear resistance tests were performed on a specially designed bench, with the use of isotope markers. Verification of each of the friction couples was based on using the wear of the ring as a function of the distance trip, and the roughness of the cylinder liner and ring.

18

Erratum to: Simulation and bench studies of the constructively and technologically modernized high performance piston aircraft engine. Stage I

Ostapski W., Wierzchoń T., Rudnicki J., Dowkontt S.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2017

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Vol. 65, nr 2

273--275

EN

In Ostapski et al., Bull. Pol. Ac.: Tech 65(1), 93-105 (2017), doi: 10.1515/bpasts-2017-0012, an analysis of tribological wear of an assembly composed of cylinder liner and piston rings in a piston aircraft engine was presented. In place of the previously used technology of gas nitriding of the cylinder liner (made out of 38CrAlMo6-10 steel), formation of multi-component or composite layers by nitriding in plasma discharge environment was proposed. Also, a modification of the previously used chromium coating of the piston rings by plasma nitriding was proposed. A study on the structure and properties of surface layer diffusion manufactured by utilizing the phenomenon of cathode sputtering was carried out. Wear resistance tests were performed on a specially designed bench, with the use of isotope markers. Verification of each of the friction couples was based on using the wear of the ring as a function of the distance trip, and the roughness of the cylinder liner and ring. This note corrects flaws in illustrations published in the original paper.

19

Fuel injection influence at engine start-up moment on diagnostic parameter blow – by phenomenon

Balitskii A., Abramek K. F., Mrozik M., Stoeck T., Osipowicz T.

Badania Nieniszczące i Diagnostyka

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2017

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nr 1-2

36--38

EN

The paper presents the diagnostic of exhaust gas scavenging crankcase combustion piston diesel engine SB-3.1 speed boot. In the measurements, the influence of fuel injected into the engine start-up phase of the value of the intensity of exhaust gas scavenging.

PL

W referacie przedstawiono diagnostykę przedmuchów gazów do skrzyni korbowej tłokowego silnika spalinowego o zapłonie samoczynnym SB-3.1 dla prędkości rozruchu. W pomiarach analizowano wpływ wtryskiwanego paliwa w fazie rozruchu silnika na wartość natężenia przedmuchów gazów.

20

Kształtowanie i ocena mikrogeometrii eksperymentalnych tłoków o schodkowym profilu powierzchni nośnej

Wróblewski E., Iskra A., Babiak M.

Autobusy : technika, eksploatacja, systemy transportowe

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2017

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R. 18, nr 6

1133--1136, CD

PL

Kształt mikrogeometrii powierzchni nośnej tłoka jest bezpośrednio połączony ze zjawiskami rozszerzalności cieplnej, ruchów poprzecznych tłoka oraz procesu tarcia pomiędzy tłokiem a gładzią cylindra. Podczas badań schodkowego profilu powierzchni nośnej tłoka należy więc ocenić jego wpływ na straty tarcia oraz sprawność mechaniczną silnika spalinowego. W celu uzyskania najlepszego możliwego wyniku procesu modyfikacji mikrogeometrii powierzchni nośnej tłoka, wymaga to oceny dokładności jego wykonania. W artykule przedstawiona została metodyka przeprowadzonych pomiarów za pomocą maszyny współrzędnościowej. Uzyskane wyniki pozwolą ocenić stopień zużycia powłoki grafitu.

EN

The shape of the microgeometry of the piston bearing surface is directly connected to the phenomena of thermal expansion, lateral movements of the piston and the friction process between the piston and cylinder. During the research the stepped profile of the bearing surface of the piston should be appraised of influence on the friction loss and the mechanical efficiency in internal combustion engine. In order to achieve best possible result of the modification process microgeometry bearing surface of the piston, this requires assessing the accuracy of implementation. The paper presents the methodology of measurements using CMM. The results will determine the degree of wear coating graphite.