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Heavy Duty, Equipment, and Off-Highway Parts

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This forum is for heavy duty, equipment, and off-highway parts topics. Examples of fitment would be for big semi trucks, excavators, loaders, compressors, farm equipment, etc.

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    • Structural form of engine suspension mount In the design of engine mount, the purpose of mount, such as the quality of support and limited displacement, must be fully considered, and the reasonable shape must be chosen. There are three basic types of mounting: compression, shearing and tilting (see figure below).(Thanks for the help and support of Chongqing Feilong Jiangli Auto Parts technical department) If the displacement of the power assembly is too large, the total power cost will be caused, or the intake and exhaust system, control mechanism, pipeline, wiring and other peripheral parts will be damaged. At the same time, the mounting cushion is easy to damage. For this reason, suspension stiffness must be limited from overhanging structure 1, plus larger displacement. For example, when a car is accelerating or turning, the inertia force generated by the power assembly may cause a greater displacement of the power assembly. In order to limit the displacement of power assembly, it is necessary to design rigid suspension, that is, large stiffness suspension cushion 2, nonlinear and variable stiffness suspension structure, in order to reduce the vibration caused by small exciting force and limit the large vibration displacement when large exciting force. For example, the engine output torque is small when the car stops idling, or when the car runs at a constant speed. At this time, the lower stiffness of the suspended cushion should be designed to effectively isolate vibration. But in the fast start, the reaction force of the driving torque is very large, which can make the power assembly produce greater vibration. In addition, when the vehicle is running on uneven road surface, with the large ups and downs of the whole vehicle, the dynamic assembly also produces great up and down inertia. At this time, the stiffness of the suspension cushion is increased, which can effectively limit the vibration and position of the power assembly. Shift
    • The number of mounting points depends on the length, mass, use and installation of the power assembly. The mounting system can be mounted at 3, 4 and 5 points. Generally, three-point and four-point mounting systems are used in automobiles, because if the number of mounting points increases when the vibration is relatively large, when the body deformation, some mounting points will be dislocated, so that the engine or mounting bracket force is too large and cause damage to the three points, the advantages of the support is that no matter how bumpy and jumping the car, it can always ensure the support. The point is in a plane, which greatly improves the force condition of the body. The front and rear suspensions of the four-point mount are mainly used to prevent the torsion of the power assembly, and the torsional stiffness is larger than that of the three-point mount. Three point mounting system Left suspension: connect with gearbox, mainly power assembly limit and supporting function. The right suspension: connected with the engine, it can isolate the engine, such as vibration, inertia force and vibration. Rear suspension: It is connected with the gearbox, and has the functions of longitudinal limit, bearing torque, driving condition limit and so on. Four point mounting system It can overcome the large torsional reaction force, but the torsion stiffness is large, which is not conducive to the isolation of low frequency vibration. Left and right suspension: close to the torsional inertia axis, support the powertrain up and down, and have the function of vibration decoupling. Front and rear suspension: with the transmission, it has longitudinal limit, driving condition limit and torque endurance.  
    • According to the engineer's statement of Feilong Jiangli .Automobile water pump is the key component of the engine cooling system. One end of the pump bearing inputs torque through the pulley, which drives the other end of the blade to rotate. In order to meet the development requirements of high power and high efficiency of the engine, higher performance requirements for pump bearings are put forward. Fracture, corrosion, peeling and grease leakage are common failure modes of automobile water pump bearings. Fracture is the most harmful. Therefore, it is necessary to analyze the failure modes of fracture and formulate corresponding preventive measures. The chemical composition, hardness, metallographic structure and heat treatment process of the broken shaft were determined by inspection and analysis to meet the requirements of relevant technical specifications. However, the toughness of the bearing after quenching is insufficient, resulting in low flexural torsional fatigue strength. The load of the pulley is transmitted to the pump bearing through the flange, and the receding groove at the back of the flange has a notch effect at the tip, which is the stress concentration position and the crack source is easy to appear. Therefore, it is necessary to change the heat treatment process of the pump bearing and optimize the geometry of the pump shaft.
    • Engine cooling water pump is the main part of the cooling system of automobile engine. Its function is to force the cooling fluid in the engine to circulate in the cooling system and reduce the influence of high temperature on the engine during the working process of the engine. Water seal is the core of the work of the pump. The movement of the water seal itself is very simple, just rotates with the shaft. . Water seal, pump body and bearing are super-hard matching mechanical seals. This kind of seals is composed of static rings and dynamic rings, which are perpendicular to the shaft, and the smooth and straight surface of each other, and do relative rotation. Coolant movement in the pump is very complex, different types of water seals, using different types of coolant, if the water package is equipped with problems, the engine coolant will appear seepage, then the pump bearing lubrication will be washed away, the entire pump function will be invalid. There are two main types of water seals: one is separated (rotating ring parts and static ring parts are respectively installed on the pump), the other is integrated (rotating ring parts and static ring parts are first installed together, and then installed on the pump), separated water seals are mainly used in larger pumps, now commonly used is integrated water seals.
    • Introduction of defects in rubber products vulcanizing 1.Lack of glue: due to insufficient weight or poor fluidity, some defects should be found in rubber parts. 2.Degumming: the failure of rubber and frame inserts will result in disengagement or separation. 3.Bubbles: also known as "bulging", because the gas is coated in the rubber epidermis and the formation of local epidermis blistering phenomenon; Thanks for the help and support of Chongqing Feilong jiangli’s  Technical department. 4.Rotten bubbles: also known as "pit gas", because the gas has not been discharged from the cavity, so that the die corner of the rubber cavity is less sulfur sticky, and protruding from the surrounding rubber surface phenomenon 5.Gel cracking: a phenomenon of cracking on the glue surface. 6.Under sulfur: the inner surface of the gum is microporous, and the exterior is uplifted and deformed. 7.Sticking mould: the phenomenon that the local glue of vulcanized product is adhered to the wall of the mold cavity. 8.Hot die: also known as curling edge, "bite edge" and so on, refers to the product parting line is not smooth, cracks, serrated waste edge and other phenomena.

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