RU2455519C1 - Testing method of high pressure instruments of fuel system of diesel on operating engine, and device for its implementation - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: testing method of high pressure instruments of diesel fuel system on operating engine consists in measurement of maximum pressure and duration of fuel injection with injector to diesel cylinders, fuel supply and injection beginning angle, residual fuel pressure in high pressure fuel line and fuel injection advance angle. In addition, during the test there measured are phase parameters of operation of high pressure fuel pump sections, capacity and non-uniformity of fuel supply with high pressure fuel pump sections by dynamic measurement of fuel flow consumption at in-series connection of one measuring channel to each pump section. Device for implementing the above method includes measuring devices of maximum pressure and duration of fuel injection with an injector to diesel cylinders, fuel supply and injection beginning angle, fuel injection advance angle, residual fuel pressure in high pressure fuel line, which are connected to information control and processing system; in addition, it includes measuring devices of fuel, capacity and non-uniformity of fuel supply with high pressure fuel pump sections, which are made in the form of an injector, connecting fuel lines and flow metre located after the injector in fuel flow direction, and measuring devices of phase parameters of operation of high pressure fuel pump sections, which are made in the form of pressure sensor installed between the measured pump section and injector, and angular movement sensor connected to the pump drive shaft. Pressure sensor, injector, connection fuel lines and flow metre are combined in one measuring channel provided with possibility of alternate connection to each section of high pressure fuel pump.

EFFECT: improving the accuracy of evaluation of the technical state of high pressure instruments of diesel fuel system at operation without ICE removal.

Description

The invention relates to mechanical engineering, in particular to the field of technical diagnostics of diesel fuel equipment.

Power, economic and environmental indicators of diesel engines to a large extent depend on the technical condition of the high-pressure devices of the fuel system - nozzles and high-pressure fuel pumps (TNVD). During operation, the pump parameters often go beyond the regulated values. This makes it necessary to periodically technical diagnose the injection pump during operation without dismantling it from the engines.

Known methods for assessing the technical condition of high-pressure devices of the fuel system without dismantling from engines (ICE), based on the simultaneous measurement of several parameters of the nozzles and fuel injection pump, and devices for their implementation, made in a compact portable version [1-4].

Existing diagnostic tools for assessing the technical condition of fuel injection pumps without dismantling them from the internal combustion engine allow to identify malfunctions of individual parts and assemblies and determine the following parameters of the operation of the diesel fuel system devices:

a) on a running engine:

- maximum pressure of fuel injection into diesel cylinders;

- residual fuel pressure in the high pressure pipeline;

- duration of fuel supply (duration of injection);

- lead angle of fuel supply;

- engine speed;

- uneven engine speed;

b) on an idle engine:

- pressure developed by the plunger pair of injection pump;

- pressure drop in the cavity of the injection valve of the injection pump;

- the angle of the beginning of the supply and injection of fuel;

- lead angle of fuel injection;

- fuel pressure in the head cavity of the injection pump;

- fuel injection pressure by nozzle.

At the same time, such defining parameters of the efficiency of the fuel injection pump (provided by GOSTs and working technical materials (RTM)), such as:

- cyclic fuel supply by pump sections;

- uneven fuel supply between pump sections;

- phase parameters of the sections of the high pressure fuel pump are not monitored.

As a prototype of the proposed method, the method of testing high-pressure devices of the diesel fuel system on a running engine is selected, which consists in measuring the maximum pressure and duration of fuel injection by the nozzle into the diesel cylinders, the angle of the start of fuel supply and injection, the residual fuel pressure in the high pressure fuel line and the angle of advance of injection fuel [1].

The device with which the known method is implemented is an M3-2 motor tester, which contains means for measuring the maximum pressure and duration of fuel injection by the nozzle into the diesel cylinders, the angle of the start of fuel supply and injection, the residual pressure of the fuel in the high pressure fuel line and the angle of advance of fuel injection, associated with the information management and processing system [1].

Figure 1 shows a diagram of a known design of the device (motortester M3-2) for testing high-pressure devices of the diesel fuel system on a running engine. The device consists of a control unit (microprocessor device) 2, to which incoming signals are connected from a pressure sensor 4, installed between the nozzle 5 and the fuel line 8 connecting it to the fuel injection pump section 6, stroboscope 3 and connecting devices 9. To save, process and display the results test to the control unit 2 is connected to the computer 1.

A disadvantage of the known method and device for its implementation is the impossibility of directly measuring the magnitude of the cyclic fuel supply and the uniformity of its distribution over the diesel cylinders, the phase parameters of the sections of the high pressure fuel pump, without measuring which to make an objective conclusion about the technical condition and quality of the injection pump adjustment without dismantling it with ICE is not possible.

The technical result is aimed at improving the accuracy of assessing the technical condition of high-pressure devices of the diesel fuel system during operation without dismantling from the internal combustion engine.

The technical result is achieved by the fact that in the method of testing high-pressure devices of the diesel fuel system on a running engine, which consists in measuring the maximum pressure and duration of fuel injection by the nozzle into the diesel cylinders, the angle of the start of fuel supply and injection, the residual fuel pressure in the high-pressure fuel line and the lead angle fuel injection, additionally during the test, the phase parameters of the operation of the sections of the high-pressure fuel pump are measured, productivity and uneven supply of fuel by sections of the high-pressure fuel pump by dynamically measuring the flow rate of the fuel when connecting one measuring channel to each section of the pump in series.

A device for implementing the inventive method, comprising means for measuring the maximum pressure and duration of fuel injection by the nozzle into the cylinders of the diesel engine, the angle of the beginning of the supply and injection of fuel, the angle of advance of fuel injection, the residual fuel pressure in the high pressure fuel line, additionally contains information management and processing system means for measuring fuel temperature, performance and unevenness of fuel supply by sections of a high-pressure fuel pump made in the form of a nozzle, connecting fuel lines and a flow meter located after the nozzle along the fuel flow, and means for measuring the phase parameters of the sections of the high-pressure fuel pump, made in the form of a pressure sensor installed between the measured section of the pump and the nozzle, and an angular displacement sensor associated with the pump drive shaft, while the pressure sensor, nozzle, connecting fuel lines and flow meter are combined into one measuring channel, made with the possibility of pocher -stand connected to each section of the high pressure fuel pump.

Distinctive features are that when testing high-pressure devices of the diesel fuel system on a running engine, the phase parameters of the sections of the high-pressure fuel pump sections, the performance and unevenness of the fuel supply by the sections of the high-pressure fuel pump by dynamically measuring the flow rate of the fuel when connecting one measuring channel in series are additionally measured to each pump section, for which the test device further comprises means of measuring the fuel temperature, performance and unevenness of the fuel supply by the sections of the high-pressure fuel pump, made in the form of a nozzle, connecting fuel lines and a flow meter located after the nozzle along the fuel flow, and means for measuring the phase parameters of the sections of the high-pressure fuel pump, made in the form of a sensor the pressure established between the measured section of the pump and the nozzle, and the angular displacement sensor associated with the pump drive shaft, while the sensor yes Lenia, the nozzle, and connecting the fuel flow meter integrated into one measuring channel arranged to alternately connect to each section of the high pressure fuel pump.

Figure 2 shows a diagram of the proposed design of a device for testing high-pressure devices of the fuel system of a diesel engine running, different from the prototype in that it further comprises means for measuring fuel temperature (not shown), productivity and unevenness of fuel supply by sections 6 of the high-pressure fuel pump 7 made in the form of a nozzle 14 installed hermetically in the discharge chamber 12 of the portable housing 13 of the device, the connecting fuel lines 10, 11, 15, 18 and the flow meter 1 7, located after the nozzle 14 along the fuel flow, and means for measuring the phase parameters of the sections of the high-pressure fuel pump, made in the form of a pressure sensor 4 installed between the measured section 6 of the pump 7 and the nozzle 14, and an angular displacement sensor (not shown), associated with the drive shaft of the pump 7, the pressure sensor 4, the nozzle 14, the connecting fuel lines 10, 11, 15, 18 and the flow meter 17 are combined into one measuring channel, made with the possibility of alternately connecting to each section of the fuel th high pressure pump. The temperature measurement of the fuel is carried out by a temperature sensor mounted in the housing of the fuel flow meter 17. The operation of the device proceeds under the control of a control unit 2, to which control and signal circuits of a flowmeter 17 with a temperature sensor, a pressure sensor 4, a strobe light 3, a power supply 19, an angular displacement sensor (not shown) and a computer 1 are connected by means of connecting devices 9.

The proposed method is as follows. On an idle engine, disconnect the high pressure fuel line connecting the test section of the injection pump to the nozzle. From the elements of the device’s kit, a measuring channel is assembled as part of a pressure sensor 4 connected to the connecting fuel line 11 of the nozzle 14, which is sealed in the discharge chamber 12 of the portable case 13 of the device. The tight installation of the nozzle 4 provides excessive pressure in the discharge chamber 12, which increases the reliability of fuel intake to the flow meter 17 as part of the fuel measuring channel. The chamber 12 is connected by a connecting fuel line 15 to the flow meter 17 so that it is located at least 0.7 m below the chamber 12. Then, a drain fuel line 18 is connected to the drain fitting of the flow meter 17, the free end of which is placed in a fuel collecting tank or fuel tank vehicle (not shown). After this, a flexible high-pressure fuel line 10 connects the test section 6 of the injection pump with a pressure sensor 4.

An angular displacement sensor is installed on the drive shaft of the pump 7 (not shown in the figure), after which control and signal circuits of the flowmeter 17 with a temperature sensor, pressure sensor 4, strobe 3, power supply 19, angle sensor are connected to the control unit 2 by means of connecting devices 9 movements (not shown in the figure) and computer 1.

The vehicle’s engine is started, the crankshaft rotational speed is set equal to the rotational speed at the nominal value of the engine torque, the test mode is selected using computer 1, and by setting the required number of fuel supply cycles, the average cyclic fuel supply is measured using the flow meter 17 flowing through a flowmeter fuel flow.

The phase parameters of the section — the start angle of injection or fuel injection, the duration of fuel injection — are determined using an angular displacement sensor (not shown in the figure), which measures the angle of rotation of the output shaft of the actuator 3, and a pressure sensor 4, which measures the actual fuel pressure in front of the nozzle. In this case, each value of the angle of rotation of the output shaft of the injection pump drive is associated with a pressure value measured by the sensor 4 at a given angle.

The set values of the angles of the beginning of the injection, the advance of fuel injection, the cyclic fuel supply, corresponding to the characteristics of the tested injection pump, are entered into the memory of computer 1 in advance.

The output signals from the angular displacement sensor, pressure sensor 4, flow meter 17 are received in block 2, which serves to process the signals of the sensors and communication with computer 1.

The angle of advance of fuel injection is measured using a strobe 3 when the engine is running at minimum idle speed.

The results are entered into the electronic test report in the memory of computer 1.

After completing the measurement of the parameters of one section of the high pressure fuel pump, the high-pressure flexible fuel line 10 is connected in series to the second section of the high pressure fuel pump, the process of measuring parameters is repeated, etc. for each subsequent section.

Upon completion of testing all sections of the injection pump, based on the processing of the obtained measurement results, a computer displays a diagram of the cyclic fuel supply by the injection pump sections in comparison with its set value, calculates the unevenness of the fuel supply by the injection pump sections, the phase parameters of the sections, which allows an objective conclusion about its technical condition and the need for adjustment work.

To assess the technical condition of only the high pressure fuel pump as a nozzle 14 as part of the measuring channel of the device, it is advisable to use one (common for testing all sections of the high pressure fuel pump) a serviceable and pre-adjusted nozzle of the same type that is used on the engine.

To assess the technical condition of the injection pump and the injector during their joint operation, it is advisable to use the nozzles of the test engine pre-adjusted at the stand as part of the measuring channel of the device, designed to work with the corresponding sections of the injection pump.

Measurement of the parameters of all sections of the pump using one measuring channel with a reduction in the number of nozzles used to one eliminates the relative measurement error of the parameters of the various sections of the pump.

Measurement of fuel consumption in dynamics using a flow meter allows you to increase the accuracy of the measurement of the pump parameters and to exclude the influence of the subjective factor on the measurement process.

Using for measuring the phase parameters of the pressure sensor and the sensor of the angle of rotation of the cam shaft of the pump allows for the direct determination of phase parameters and to increase the accuracy of their measurement.

Thus, the proposed method and device for its implementation are more advanced than known, as they increase the accuracy of the assessment of the main parameters of the fuel injection pump during testing, and therefore, improve the quality of diesel fuel equipment.

Literature

1. Motortester M3-2. Operation manual KSYuA.461263.001 OM. It is registered in the State Register of Measuring Instruments of the Russian Federation under No. 20820-01.

2. Guidelines for technical diagnostics during maintenance and repair of tractors and agricultural machinery / A.E. Severny, D.S. Buklagin, V.M.Mikhlin, etc. Under the arms. Academician V.I. Chernoyvanov - M .: Federal State Institution "Rosinformagroteh", 2001.

3. RF patent 2231674. Tester of diesel fuel equipment / V.N. Khabardin, A. V. Khabardin - Publ. in BI No. 18, 2004.

4. RF patent 2240440. Tester of the diesel fuel pump / V.N. Khabardin, S. V. Khabardin - Publ. in BI No. 32, 2004.

Claims (2)

1. The method of testing high-pressure devices of the diesel fuel system on a running engine, which consists in measuring the maximum pressure and duration of fuel injection by the nozzle into the diesel cylinders, the angle of the start of fuel supply and injection, the angle of advance of fuel injection, the residual fuel pressure in the high pressure fuel pipe, characterized in that, in addition, during the test, the phase parameters of the sections of the high-pressure fuel pump sections are measured, the productivity and the irregularity of the feed t fueling by sections of the high-pressure fuel pump by dynamically measuring the flow rate of the fuel with the serial connection of one measuring channel to each section of the pump. 2. The device for implementing the method according to claim 1, containing means for measuring the maximum pressure and duration of fuel injection by the nozzle into the diesel cylinders, the angle of the beginning of the fuel supply and injection, the angle of advance of the fuel injection, the residual fuel pressure in the high pressure fuel line, associated with the control system and information processing, characterized in that it further comprises means for measuring fuel temperature, performance and unevenness of fuel supply by sections of the fuel pump high pressure, made in the form of a nozzle, connecting fuel lines and a flow meter located after the nozzle along the fuel flow, and means for measuring the phase parameters of the sections of the high pressure fuel pump, made in the form of a pressure sensor installed between the measured section of the pump and the nozzle, and an angle sensor displacements associated with the pump drive shaft, while the pressure sensor, nozzle, connecting fuel lines and flow meter are combined into one measuring channel made with by alternately connecting to each section of the high pressure fuel pump.

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