SU1645872A1 - Combustion engine cylinder and piston diagnostics - Google Patents

Description

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(21) 4697251/06

(22) 02.03.8 "

(46) 04.30.91. Bul Number 16

(71) Far Eastern Higher Marine Engineering School named after G.N. Nevelskogo

(72) M.S. Dahlmnn, V.I.Lapshin and S.A. Supon

(51) 621.43.001.5 (088.8) (56) Completion of work on fine-tuning the algorithms of the technical diagnostics system Forecast-2 and conducting a study to develop the algorithms of the Forecast-3 system. Report on research and development, State No. N 01830012594, Part 1, Л .: LVIMU, 1986, pp. 97-99. (54) METHOD FOR DIAGNOSING THE CYLINDRO PISTON MOTOR OF INTERNAL COMBUSTION ENGINE

(57) The invention is intended to improve the accuracy of diagnosis of the cylinder piston group of an internal combustion engine. The cylinder sleeve temperature is measured at no less than three points evenly spaced around its circumference at a given height, the maximum temperature, the maximum temperature transition and the background temperature of the sleeve are determined, and the rate of temperature change around the sleeve circumference is calculated. Then, in six combinations of these parameters, in comparison with the corresponding standards, the diagnosis is carried out.

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The invention relates to the field of operation and can be used in diagnosing the cylinder-piston group of internal combustion engines.

The purpose of the invention is to improve the accuracy of diagnosis.

The method is verified as follows.

The cylinder of the diagnosed cylinder is equipped with temperature sensors (thermocouples), marking them evenly around the circumference at the same level along the height of the sleeve;

With the engine running, a measurement cycle is performed that includes a single measurement of the temperature of the cylinder liner in series at all measurement points. According to the results of the measurement cycle, the maximum temperature TMai (C, characterizing the location of the upper piston ring) is determined as diagnostic parameters; the maximum temperature difference II w TMЈUe- T is determined, where the minimum temperature measured in the cycle is. P d characterizes asymmetry the temperature of the cylinder sleeve at this level.Also, determine the background temperature of the sleeve, which characterizes the overall temperature

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nail vuchkp cylinder, the form-P

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Where

T is the temperature value of the sleeve in the i-th measurement point (, ..., p)

n - the number of measurement points. The measurement cycles and the procedure for determining the diagnostic parameters are periodically (6 times a day or more), the results of several measurement cycles determine the speed of movement of the maximum temperature V around the circumference as a diagnostic parameter characterizing the mobility of the upper piston ring. VM speed is determined, for example, by the formula

v, h

where S is the circumferential distance

bushings from the temperature sensor, which in the last measurement cycle recorded the maximum temperature to the sensor, which in one of the previous measurement cycles recorded the maximum temperature of the sleeve;

h - the time between measurement cycles.

As a preliminary preparation for conducting diagnostics, a series of cycles of sleeve temperature measurements and determinations of these diagnostic parameters are carried out on a fully serviceable engine for various operating modes. Simultaneously with measuring the temperature of the sleeve, they record the parameters characterizing the mode of operation, the load on the engine, the parameters of the workflow and other characteristics. Based on the results of these measurements, the standard mathematical models are used to determine the reference (corresponding to a fully serviceable motor) values of the diano parameters and determine the errors of the reference models.

The diagnostic parameters obtained by the proposed method are compared with their reference values and, based on the comparison results, they are made

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water on the technical condition of the engine cylinder to be diagnosed.

To compare the cleared parameters with the reference ones, the level at which each parameter is located relative to its standard is determined. The division of the range of values of diagnostic parameters into separate levels is carried out taking into account the errors of diagnostic parameters. If the value of the diagnostic parameter differs from its reference value by no more than the magnitude of the error of this parameter (in the positive or negative direction), then consider that this parameter is at the level. If the value of the diagnostic parameter is less than its reference value by more than the magnitude of the error of this parameter, then consider that this parameter is at the level. If the value of the diagnostic parameter is greater than its reference value by more than the magnitude of the error of this parameter, then this parameter is considered to be at the level.

In the process of comparing the diagnostic parameters with their reference values, the following aggregates are revealed and the corresponding conclusions are drawn.

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. tl oh PM

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+ make a conclusion about isp0

or equality of parts of the cylinder-portnee group of an internal combustion engine.

At t

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T - llj.ll n - H .11

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Vn o or + make a conclusion about the general deterioration of the technical condition of the cylinder-portnoy group of the engine and the appearance of dry friction.

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P ".. T - M. II t II H, tm 11,11

PRI TM (t + T f ° P M +

Vn o, or + conclude that the microadrules or the developing rubbing of the bushes occur.

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 And ii

t - 1 p - o, p

M

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n -, conclude that the cylinder bushing is one-sided overheating from gases, piercing through the upper piston ring lock.

n "., t - m etc . and n p and

AT tkk °. Vn o or make a conclusion about significant wear of the piston rings and the cylinder liner, deterioration of the sealing ability of the set of png rings.

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P . T - L “T - J.. P -

AT tmax ° TF, PM - o or + conclude that the cooling conditions of the parts of the cylinder-mounted group, which are unstable or improperly maintained in the cooling mode and contaminated with the cooled surfaces, are violated.

Claims (1)

Invention Formula A method for diagnosing a cylinder-piston group of an internal combustion engine, which includes a periodic measurement of the temperature. M. Kelemesh editor Compiled by A. Aristov Tehred m.DidykKorremnorN.Revska Order 1347 Circulation 360 VCHIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 4/5, Moscow, Zh-35, Raushsk nab. 113035 Production and publishing plant Patent, Uzhgorod, st. Gagarin, 101 6458726 Perimeters of the cylinder liner at points evenly spaced around the circumference at a certain height, determining the values of diagnostic parameters and comparing them with a standard, characterized in that, in order to improve accuracy, the sleeve temperature is measured in three and 1 more points around the circumference, the maximum temperature, the maximum temperature difference, the background temperature of the sleeve, the rate of change of the maximum temperature around the circumference of the sleeve, and the diagnosis are evaluated by a combination of the values of these parameters are defined as diagrams of the static parameters. Subscription