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2017-11-05
Technical Paper
2017-32-0070
Stephan Jandl, Patrick Pertl, Hans-Juergen Schacht, Stephan Schmidt, Stefan Leiber
The development of future internal combustion engines and fuels is influenced by decreasing energy resources, restriction of emission legislation and increasing environmental awareness of humanity itself. Alternative renewable fuels have, in dependency on their physical and chemical properties, on the production process and on the raw material, the potential to contribute a better well-to-wheel-CO2-emission-balance in automotive and nonautomotive applications. The focus of this research is the usage of alcohol fuels, like ethanol and 2-butanol, in motorcycle high power engines. The different propulsion systems and operation scenarios of motorcycle applications in comparison to automobile applications raise the need for specific research in this area.
2017-11-05
Technical Paper
2017-32-0071
Jürgen Tromayer, Michael Gaber, Roland Kirchberger, Fern Thomassy, Scott McBroom
Abstract Meeting upcoming emission limits such as EURO 5 with comparatively simple and low-cost vehicles will be very challenging. On the engine side, a big effort in terms of fuelling, combustion optimization as well as exhaust gas aftertreatment will be necessary without any doubt. Besides that, additional system optimization potential can be gained by a systematic adaptation of the drive train. One approach is to use a CVT (Continuously Variable Transmission) system to run engines in specific ranges with good fuel economy. However, existing belt driven CVTs show comparatively poor efficiencies. To overcome this drawback, the integration of a novel Continuously Variable Planetary Transmission (CVP), designed and developed by Fallbrook Technologies, was investigated in detail. For this purpose, a longitudinal dynamics simulation in Matlab-Simulink was carried out to compare a standard mass production vehicle drive train with several CVP setups.
2017-11-05
Technical Paper
2017-32-0076
Adyati Yudison, Driejana, Iman K. Reksowardojo, Aminudin Sulaeman
Motorcycles account for almost 80% of private vehicles in Indonesia, with an annual growth rate of 12% per year. This paper aims to investigate the emission profiles of CO2, CO, HC and NOx based on typical fuel and motorcycle types in Indonesia. Questionnaire surveys were undertaken to gather fuel type, engine technology and capacity representing the motorcycle population in Bandung City, Indonesia. Emissions were measured based on six-speed variations on a chassis dynamometer. Questionnaire surveys from 290 respondent show that EURO II and EURO III technology with engine capacity less than 150cc is the most utilized type of motorcycle in Bandung. Most of the users’ chose RON 90 and RON 92 gasoline. Based on the results, four groups of 5 motorcycle of EUROII-RON90, EUROII-RON92, EUROIII-RON90, and EUROIII-RON92 were tested. Emission data showed that the higher the speed, the lower the emission, except for CO and NOx which have a different pattern.
2017-11-05
Technical Paper
2017-32-0083
Makoto Hasegawa, Takanobu Kaneko
ISO 26262, an international functional safety standard of electrical and/or electronic systems (E/E systems) for motor vehicles, was published in November 2011 and it is expected that the scope will be extended to motorcycles in a second edition of ISO 26262 going to be published in 2018. ISO/DIS 26262 second edition published in 2016 has Part 12 as a new part in order to apply ISO 26262 to motorcycle. Proper estimation of Exposure, Controllability, and Severity in accordance with ISO/DIS 26262 Part 12, are key factors to determine Motorcycle Safety Integrity Level. To estimate precise these factors, there would be a case that it might not be appropriate to apply studies done for passenger car to motorcycle, and it would be necessary to apply motorcycle specific knowledge and estimation methods. In our previous studies we clarified these motorcycle specific issues and studied the method for the adaptation.
2017-11-05
Technical Paper
2017-32-0074
P. Rieger, B. Schweighofer, H. Wegleiter, Ch. Zinner, St. Schmidt, R. Kirchberger, N. Foxhall, W. Hinterberger
Within the motorcycle- and powersport sector the hybridization and electrification of the powertrain is increasingly becoming an important topic. In the automotive sector the hybridization of the powertrain is already well established and shows improvements regarding fuel consumption and emission behavior. Also in the motorcycle sector the emission legislation limits are getting stricter and the requirement for a significant reduction of fuel consumption, especially under real drive condition, is being focused. Furthermore, the increasing environmental awareness of the customer requires measures regarding fuel consumption- and emission minimization. Due to the high system complexity and degrees of freedom of hybrid powertrains, the simulation of the complete vehicle is essential for the component dimensioning, concept selection and the development of operation strategies.
2017-11-05
Technical Paper
2017-32-0082
Pierre Duret, Stéphane Venturi, Antonio Sciarretta, Nigel Foxhall, Walter Hinterberger
The main purpose of this paper will be to investigate if a small snowmobile gasoline Direct Injected (DI) two-stroke engine has the potential to be adapted for two other types of applications: as a range extender (REX) for electric vehicles and for a motorcycle application. For the REX application, the main requested specifications (NVH, lightweight, compactness, minimum production cost and easy maintenance), correspond well to the main features of DI 2-stroke engines. The potential of a modified production engine operating in part load ultra-low NOx Controlled Auto Ignition (CAI) to meet the Euro 6 emissions standards on the NEDC cycle has already been demonstrated in a previous paper. In the first part of this new paper, we will investigate which solutions can be used to maintain this potential with even stricter legislations based on Euro 6d, WLTP cycle and Real Driving Emissions (RDE).
2017-11-05
Technical Paper
2017-32-0087
Sangriyadi Setio, Wiranto Arismunandar, Rudy Ong, Adefrid Dwithama, Stefanus Adrian, Angela Claudia, Nu’man Amri Maliky, Jery Octavianus, Muhammad Alif Mabbrur, Michell Tjhoi
Developing and designing fuel efficient vehicle for a one gallon of fuel marathon is a challenging task. Engines have to be optimized to achieve maximum fuel efficiency. In this study, we evaluate the optimal compression ratio (CR) and ignition timing that produce the best torque in a custom gasoline-based-motorcycle-engine that use ethanol E100 fuel. In the first experiment, CR was adjusted between 9 and 12 to evaluate its effect on the engine mileage’s record. The experiment was conducted on the test track. In the second experiment, Ignition timing was adjusted by a custom-made engine control unit (ECU) between 15° and 45° before top dead center (BTDC). The engine performance was investigated in terms of best torque and brake specific fuel consumption (BSFC), with variation of engine speed between 1500 and 8000. The test was conducted on dynamometer. The test was also performed in constant compression ratio and stoichiometric air-fuel ratio, 9.
2017-11-05
Technical Paper
2017-32-0086
Shinji Takayanagi, Kiyotaka Sakai, Takashi Iwasa, Tomoyuki Matsumura, Shigehiro Yamaguchi, Kenji Tanaka
A low fuel consumption tire with an affordable price that is applicable for small motorcycles marketed mainly for India and Southeast Asian countries was developed. Two contradicting requirements, which are reduction of the rolling resistance and retention of the wet grip performance, were satisfied by applying a method based on viscoelastic properties of the tread rubber. Regarding the composition of compound of the tread rubber, the amounts of carbon black and oil were reduced instead of using silica. In addition, a polymer having a high glass transition temperature was employed. Moreover, response to the roll motion, which is unique in motorcycles, was made satisfactory to the requirement by modifying the dynamic modulus E* of the tread rubber. With those measures, the rolling resistance was reduced by more than 15% to conventional tires while maintaining the basic performances such as tire grip and stability in maneuvering.
2017-11-05
Technical Paper
2017-32-0052
Katsunori Tasaki
Misfire is the condition where the engine does not fire correctly due to an ignition miss or poor combustion of the air fuel mixture, resulting in serious deterioration of tailpipe emissions due to the discharge of unburned gas. In order to prevent further exacerbating environmental problems, misfire detection is obligatory in On Board Diagnosis (OBD) II systems. OBD II technology for passenger cars cannot be easily adopted to motorcycles for several reasons. However, very little research has been reported on misfire detection for an unevenly firing engine in which the degree of contribution to engine output and the variation pattern of angular velocity show a large difference between cylinders, an aspect that is unique to motorcycles. This research focuses on uneven firing V-twin motorcycle engines, to explore misfire detection techniques using variation characters in crank angular velocity.
2017-11-05
Technical Paper
2017-32-0053
Alexander Winkler, Gernot Grabmair
In this study we focus on systematic disturbances caused by the motorcycle pitch dynamic when measuring longitudinal acceleration on motorcycles using low-cost acceleration sensors. Major systematic influences in the sensor measurement like gravitational acceleration, suspension dynamics and the road slope are addressed. During acceleration phases the motorcycle pitch angle changes according to the suspension setting. As a result the longitudinal sensing axis of the accelerometer includes parts of the gravitational acceleration and lags parts of the longitudinal acceleration. Gravitational acceleration has also significant influence on inclined roads. To obtain correct values of the effective longitudinal acceleration, the disturbances in the measured signal are analyzed and in further consequence compensated. For this purpose a linearized in-plane-dynamics model of the motorcycle is derived from a comprehensive multibody simulation.
2017-11-05
Technical Paper
2017-32-0056
Hirotoshi Inui, Toru Sakurai, Eiichi Sato, Tadashi Minoda, Yasuhiro Nakai
Tapered handlebars using high strength aluminum alloys have been applied mainly to motorcycle models requiring weight reduction and high texture appearance that aluminum handlebars can offer as their characteristics. This handle bar is manufactured through extrusion processing. Conventionally used alloys had low extrusion productivity, which led to increased cost of the handlebars. In view of this, we selected an alloy securing the strength by adding a large amount of zinc while reducing the amount of the copper, which deteriorates the extrusion productivity, to the minimum adding amount, in consideration of maintaining the stress corrosion cracking resistance. However, a large amount of zinc decreases the stress corrosion cracking resistance. Therefore, in order to obtain a metallic structure favorable to the prevention of stress corrosion cracking, the mandrel extrusion was applied for the pipe manufacturing method, and heat treatment condition and swaging condition were optimized.
2017-11-05
Technical Paper
2017-32-0057
Maki Kawakoshi, Takashi Kobayashi, Makoto Hasegawa
In applying the ISO 26262 controllability classification for motorcycles in actual riding tests, a subjective evaluation by expert riders is considered to be the appropriate approach from the viewpoint of safety. We studied the construction of an expert-rider-based C class evaluation method for motorcycles and developed some evaluation test cases reproducing various hazardous events. We determined that it was necessary to accumulate more evaluation cases for further representative scenarios and that, to avoid variations in such evaluations, a method in which different expert riders can carry out testing following a common understanding had to be devised. Considering these problems for practical application, this study aimed at establishing an actual riding test method for C class evaluation by expert riders and to develop a deeper understanding of test procedures and management.
2017-11-05
Technical Paper
2017-32-0055
Yota Sakurai, Yoshinori Nakao, Astushi Hisano, Masahito Saitou, Kunihiro Tanaka
In this study on the motorcycle engine, we investigated the geometry of the newly developed intake port with an objective of improving the fuel consumption and the torque in practical range. Herein we present the results obtained. We believe that an effective measure for achieving the stated objective is to improve the combustion speed and combustion stability. To realize that, it is necessary to increase the turbulence during combustion and improve the homogeneity of air-fuel mixture. To investigate the feasible shape of the port, the CFD simulation (including fuel spray analysis) was performed and a geometry that improved the turbulent kinetic energy and mixture homogeneity at the time of ignition was selected. For confirming the combustion improvement effect achieved by tumble strengthening, an engine test was conducted with the same amount of intake air as that used in.
2017-11-05
Technical Paper
2017-32-0067
Ranjana Meena, Pradeep Ramachandra, Adwitiya Dube
With the increased demand of mobility in the form of two-wheelers and the continued dominant share of Internal Combustion Engines (ICE) in Indian market, there is considerable influence on the deterioration of air quality. The regulators in this region have legislated Bharat Stage 6 (BS6) as a measure to restrict tail pipe emissions, which necessitates the automotive industry to work towards emission optimization measures. Some of the factors influencing this includes, air-fuel mixture formation, spray targeting, fuel properties, flow dynamics, combustion chemical kinetics, exhaust after-treatment etc. The focus area of this paper is to study the influence of air-fuel mixture formation which is highly dependent on fuel droplet atomization, injection timing, fuel injector, injection pressure and mixture preparation techniques to reduce the engine out emissions.
2017-11-05
Technical Paper
2017-32-0065
Riccardo Basso, Hans-Jürgen Schacht, Schmidt Stephan, Roland Kirchberger, Matthias Rath, Markus Neumayer, Christian Reisenberger
Small engines for non-automotive and two wheeler applications have a reduced number of sensors. For fulfilling emission regulations a cost effective way is an enhanced use of standard sensors in order to obtain more information from the existing sensors. The delivered information can then be used for an on-board diagnosis. Moreover, it is important to control the quality of the product during engine production; therefore an end-of-line cold engine test is often made. With this measure it is possible to detect faults, wrong tolerances or assembly in order not to deliver faulty engines to the customers. In this paper, an enhanced use of sensors for fault detection will be discussed. It is possible to obtain more information from the signal or to use the sensor for detecting other parameters. For extracting information signal analysis methods will be used with focus on the computational power need since the ECU performance is limited.
2017-11-05
Technical Paper
2017-32-0033
Akinori Shinagawa, Hisayuki Nozawa, Yutaro Uchiyama
Two-wheeled off-road vehicles are mainly ridden on slippery dirt roads that include steep slopes and rough, uneven surfaces. An analysis method for the driving state and the vehicle movement limits that would be suitable for analyzing the movement of such two-wheeled off-road vehicles under these conditions was examined. These movement limits were then formulated by taking into consideration the coefficient of friction and the road surface gradient in accordance with the basic laws of physics and also by focusing on the vehicle movement in the longitudinal direction. Measurements were also taken during actual off-road riding by top-class Japanese off-road motorcycle riders. It was confirmed that this measurement data was distributed within the range of the assumed vehicle movement limits. Consequently, it was confirmed that it is possible to use such measurements to accurately grasp the vehicle movement limits and the associated driving state for two-wheeled off-road vehicles.
2017-11-05
Technical Paper
2017-32-0036
Gundavarapu V S Kumar, M Suresh, Manish Garg
Thermal management is of vital importance in the development of a scooter type motorcycle (two-wheeler). Traditionally the thermal management development of a two-wheeler is done through experimental methods, or using sub-system level CFD models. In current work, a comprehensive, complete vehicle, three-dimensional CFD model has been developed to assess thermal performance of the scooter and its sub-systems. The model can predict thermal performance in different operating conditions, such as, wide open throttle, idling and key-off. A typical thermal interaction in engine happens through metal contact conduction, air cooling and oil flow path in the engine. The model can capture the sub system interaction, such as, an interaction between the cooling system and engine cabin. Modeling oil is computationally expensive, as it involves complex physics modeling such as multiphase flow.
2017-11-05
Technical Paper
2017-32-0038
Rose Mary Simon Palackal, Balagovind Nandakumar Kartha, Karthikeyan Ramachandran, Srikanth Vijaykumar, Pramod Reddemreddy
Today, 99% of the two wheelers in India operate with carburetor based fuel delivery system. But with implementation of Bharath Stage VI emission norms, compliance to emission limits along with monitoring of components in the system that contributes towards tail pipe emissions would be challenging. With the introduction of the OBD II (On-Board Diagnostics) and emission durability, mass migration to electronically controlled fuel delivery system is very much expected. The new emission norms also call for precise metering of the injected fuel and therefore demands extended calibration effort. The calibration of engine management system starts with the generation of pre-calibration dataset capable of operating the engine at all operating points followed by base calibration of the main parameters such as air charge estimation, fuel injection quantity, injection timing and ignition angles relative to the piston position.
2017-11-05
Technical Paper
2017-32-0041
Johannes Hiesmayr, Stephan Schmidt, Stefan Hausberger, Roland Kirchberger, Christian Zinner, Patrick Filips, Roland Wanker, Hubert Friedl
Real world operating scenarios have a major influence on emissions and fuel consumption. To reduce climate-relevant and environmentally harmful gaseous emissions and the exploitation of fossil resources, deep understanding concerning the real drive behavior of mobile sources is needed because emissions and fuel consumption of e.g. passenger cars, operated in real world conditions, considerably differ from the officially published values which are valid for specific test cycles only [1]. Due to legislative regulations by the European Commission a methodology to measure real drive emissions RDE is well approved for heavy duty vehicles and automotive applications but may not be adapted similar to two-wheeler-applications. This is due to several issues when using the state of the art portable emission measurement system PEMS that will be discussed.
2017-11-05
Technical Paper
2017-32-0042
Johannes Hiesmayr, Stephan Schmidt, Stefan Hausberger, Roland Kirchberger, Christian Zinner, Patrick Filips, Roland Wanker, Hubert Friedl
The reduction of environmentally harmful gases and the ambitions to reduce the exploitation of fossil resources lead to stricter legislation for all mobile sources. Legislative development significantly affected improvements in emissions and fuel consumptions over the last years, mainly measured under laboratory conditions. But real world operating scenarios have a major influence on emissions and it is already well known that these values considerably differ from officially published figures [1]. There are regulated emissions by the European Commission by means of real driving scenarios for passenger cars. A methodology to measure real drive emissions RDE is therefore well approved for automotive applications but was not adapted for two-wheeler-applications yet [2]. Hence measurements have been performed on-road and on chassis dynamometer for motorcycles with the state of the art RDE measurement equipment to be prepared for possible future legislation.
2017-11-05
Technical Paper
2017-32-0045
Yoshihito Itou, Daiki Itou, Minoru Iida
Recently the response of the engine speed at starting has more importance than ever for quick start satisfying rider’s needs, as well as exhaust emissions. We have developed a simulation for studying engine and starter specifications, engine control algorithm and other engine control parameters. This system can be utilized to realize appropriate starting time by considering air-fuel ratio under various conditions. This paper addresses what are taken account of in our method. Examples applying this to a conventional motorcycle engine are shown.
2017-11-05
Technical Paper
2017-32-0002
N. Balasubramanian, G. R. Keerthi, J. T. Nithin, S. Jayabalan, T. N. C. Anand
This paper presents the results of tests using a prototype pump-integrated port fuel injector that is designed for small gasoline engines. The unique construction of the injector eliminates the need for a separate feed pump. The device is intended as a solution to meet the upcoming emission norms similar to Euro 6 standards, to be implemented in Asian countries. In particular, the Indian two-wheeler market which produces around 20 million vehicles annually [1], migrates to Bharat Stage VI (BS VI) emission standards in the year 2020. This market is largely cost-driven and currently most of the motorcycles use carburettors as fuelling systems. It is expected that the adoption of port fuel injection would be inevitable to meet the BS VI emission norms. To minimize the increase in cost due to such a change, a new injector is developed, which integrates the fuel pump within the injector, making the system simple and compact, while calling for no change in the fuel tank.
2017-11-05
Technical Paper
2017-32-0006
Yoichi Inoue, Toshiya Ohta, Hirotaka Kurita
A carburizing is widely applied for many kinds of engine components for motorcycles. On the other hand, a delayed fracture phenomenon of strengthened steel materials occurred under actual usage is a serious concern. The delayed fracture characteristics of surface modified steels such as a carburized steels followed by a tempering have a difficulty being evaluated by only measuring a partial characteristic of the hardened portion due to the existence of an inhomogeneity of a microstructure and a gradient of strength. Therefore, the studies on the characteristics of the delayed fracture of the surface modified steels are not so many. In this paper, the authors evaluated the delayed fracture characteristics of carburized and tempered actual components by comparing hydrogen desorption curves acquired with a thermal desorption spectroscopy using hydrogen-charged specimens with changing tempering conditions.
2017-11-05
Technical Paper
2017-32-0008
Pei Yi Lim, Youhei Inagaki
Sustainability trends and reduced fuel consumption as a value proposition to end users have led to an ever-increasing focus on fuel efficiency in the personal mobility segment. This is evident in the development of smaller and lighter engine hardware with optimized combustion systems as well as the lowering of engine oil viscosity grades and formulation of additives with improved friction properties. Due to the unique challenges of lubricating motorcycle engines, the development of fuel efficient motorcycle engine oil presents several technical dilemmas. The reduction of oil viscosity gives rise to durability concerns particularly in such high temperature and high speed operating conditions, while the formulation of additives with lower friction properties may affect clutch friction that is necessary for a manual motorcycle.
2017-11-05
Technical Paper
2017-32-0011
Alberto Grimaldi, Lorenzo Mucciarella, Francesco Virgilii
Concerning internal combustion engines (ICEs), the analysis and evaluation of combustion quality and pollutant agents has drawn the attention of public opinion and worldwide authorities. Moreover, combustion quality in ICEs affects the drivability of motorbikes/cars, a most important quality for the customers’ point of view. The possibility to monitor engine behavior is a target that every car/motorcycle OEM is seeking, so as to comply with legislated pollutant limits. As the EURO V OBD Stage II regulations state, starting from the year 2020 all the emission related components will need to be monitored. In particular, the legislator requests to monitor the frequency of misfires, due to possible damage to the catalytic converter; in fact, the malfunction of this component can dramatically affect exhaust gas pollutant emissions.
2017-11-05
Technical Paper
2017-32-0017
Yuzuru Sasaki, Nobuhiko Yamaguchi, Akira Arioka, Katsunori Komuro, Dai Kataoka, Shunji Akamatsu
Abstract In recent times, due to the improvement of internal cylinder flow analysis technology with Computational Fluid Dynamics (CFD), the prediction accuracy of fuel consumption and emission has improved. However, small motorcycles often have complex intake ports which restrict the layout of injectors. Therefore optimization of injection spray to achieve high combustion efficiency and less wall wetting is a challenge. In this study, we predicted fuel consumption and emission performance by the simulation result of air fuel distribution and wall wetting amount with an actual motorcycle engine model. We optimized injector nozzle length, spray angle and spray tip penetration. After the optimization, we evaluated the emission performance and fuel consumption with an actual engine. As a result, we were able to confirm the improvement of fuel consumption and emission performance.
2017-11-05
Technical Paper
2017-32-0018
Masayuki Miki, Tetsuya Kimura
The stability factor is widely used for four-wheel vehicles as an index representing the turning performance of a vehicle. Stability factor for two-wheel vehicles has been proposed as an indicator of cornering performance from the same way of thinking. In line traceability evaluation as a sensory evaluation item of motorcycles, the expressions of understeer and oversteer are sometimes used, but the relation with stability factor for two-wheel vehicles has not been investigated. In this paper, a test in which the slip angle characteristics of the front and rear tires were varied using a riding simulator was conducted, and the correlation between the stability factor and the rider evaluation was investigated to derive an index showing the line traceability.
2017-11-05
Technical Paper
2017-32-0028
Huang Hui-Hui, Tsai Chien-Hsiung, He Wei-Ta
In this study, the temperature of solid/fluid inside a continuously variable transmission (CVT) of a 400 cc scooter is investigated numerically utilizing ANSYS FLUENT. The moving reference frame (MRF) technique with conjugate heat transfer between gases and solid rotation/translation are implemented to carry out the simulation. The emphasis of the present study is put on the effects of CVT housing configuration, belt’s thermal conductivity, and the heat dissipated from the crankcase on the thermal-flow-field of CVT. The numerical results show that the temperature of the drive/driven pulleys are concurred with those of experimental results. It is found that the proposed design of partition plate inside the CVT housing can direct the flow into belt and prevent the fluid around driven and drive pulley from mixing, and can further decrease the temperatures of the belt and pulley.
2017-11-05
Technical Paper
2017-32-0099
Kazunobu Sakamoto
The purpose of this study is to improve the accuracy of durability predictions for motorcycle body components through the implementation of a fatigue analysis that uses the finite element method (FEM) to identify the fatigue failure characteristics of arc welds, die-cast aluminum alloys, and thermo-plastics. In addition to highly accurate load conditions and stress analysis, a fatigue analysis that also takes into consideration the fatigue failure mechanism is essential to making accurate durability predictions. Fatigue tests were carried out under several load conditions using specimens of several different shapes that simplified the actual structures. The fatigue life of the weld toe is assumed to be the difference of the crack propagation rate due to the loading mode. The durability of die-cast aluminum alloys was found to be sensitive to the microscopic structure due to the casting process.
2017-11-05
Technical Paper
2017-32-0131
Takashi Yokoo, Takeshi Enomoto, Masaki Morita
In recent years, the adoption of electronically-controlled fuel injection system (commonly called “FI”) of motorcycles is accelerating for the purpose of fuel efficiency improvement to meet tighter emission controls around the world and to protect global environment. The main stream of the motorcycle market is small motorcycles with an engine size of 100cc to 150cc, therefore downsizing and lowering the cost of FI products are being demanded. Pressure regulator (hereafter called P/R) installed in fuel pump module (hereafter called FPM), one of FI products for motorcycles, is being shifted to ball valve type from diaphragm type due to the downsizing demands. However, the ball valve type has problems such as abnormal noise and pressure adjusting defect that are caused by self-excited vibration.
Viewing 1 to 30 of 1063

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