Processing method of mounting surfaces and connecting holes at both ends of diesel engine exhaust pipe

Abstract

The present invention discloses a method for processing mounting surfaces and connecting holes at both ends of a diesel engine exhaust pipe, characterized in that it includes the following steps: 1) benchwork marking: a. marking a horizontal center waistline; b. marking a cross centerline; c. marking waistlines on both sides; 2) machining the exhaust pipe hexagonal flange end face and the first connecting hole; 3) machining the exhaust pipe circular flange end face and the second connecting hole. The present invention not only has accurate and reliable marking, a unified and stable reference, and precise positioning, but also has good consistency in workpiece size, and can effectively ensure the machining accuracy of the workpiece. The method of the present invention can be used when machining such inclined surfaces with a certain angle between the two sides on an ordinary digital display boring machine, and has a wide range of applications and good promotion.

Description

Technical Field

[0001] The invention relates to a method for processing a diesel engine exhaust pipe, in particular to a method for processing mounting surfaces and connecting holes at both ends of a diesel engine exhaust pipe with high processing accuracy, and belongs to the technical field of cutting processing. Background Art

[0002] like Figure 1 and Figure 2 As shown, the diesel engine exhaust pipe includes a hexagonal flange end 10, a round flange end 20 and an intake end 30, wherein the end faces of the hexagonal flange end 10 and the round flange end 20 are respectively used to install the supercharger intake pipe, and the center lines of the two installation surfaces form an angle β of 105°. In order to ensure the installation accuracy of the supercharger intake pipe, the center position dimensional accuracy of the two installation surfaces is high, and the flatness and roughness requirements are also high. Since the machining reference surfaces of the two installation surfaces are abstract spatial three-dimensional positioning surfaces, not actual specific plane positioning surfaces, when the two installation surfaces and connecting holes are processed by ordinary machine tools, their machining accuracy is often not guaranteed, thereby affecting the installation accuracy of the supercharger. When processed by a machining center, the workpiece coordinate system of the two installation surfaces and the connecting holes is difficult to establish, which brings certain difficulties to the processing. Summary of the invention

[0003] The purpose of the present invention is to provide a method for processing the mounting surfaces and connecting holes at both ends of a diesel engine exhaust pipe. The reference surface of the method is unified and stable, and the size and shape and position tolerances are extremely easy to guarantee, thereby ensuring the processing accuracy of the two mounting surfaces and connecting holes of the exhaust pipe, and the processing accuracy is high.

[0004] The present invention is achieved through the following technical solutions:

[0005] A method for processing mounting surfaces and connecting holes at both ends of a diesel engine exhaust pipe includes the following steps:

[0006] 1) Fitter marking

[0007] a. Mark the horizontal center waistline of the diesel engine exhaust pipe: support the exhaust pipe intake end horizontally on the marking table with the intake end facing downward, drive a wooden strip into the inner hole of the exhaust pipe hexagonal flange end, and make the outer side of the wooden strip flush with the end face of the hexagonal flange end of the exhaust pipe; then support the hexagonal flange end, round flange end and intake end of the exhaust pipe on several adjustable supports respectively, manually adjust the adjustable support of the intake end to keep the relatively vertical side of the hexagonal flange end in a vertical state, and use a height vernier ruler to measure the center height of the inner hole of the hexagonal flange end and the round flange end respectively, adjust the adjustable supports of the hexagonal flange end and the round flange end to make the center height of the inner hole of the two equal; finally, mark the horizontal center waistline of the exhaust pipe with a marking disk;

[0008] b. Draw the cross center line of the end face of the hexagonal flange of the exhaust pipe on the wooden strip;

[0009] c. Mark the waistline on both sides of the exhaust pipe: Clamp the round flange end of the exhaust pipe with a dividing head, level the horizontal center waistline, then rotate the dividing head 90°, measure the rotation center height of the dividing head chuck with a height vernier ruler, and adjust it through the adjustable support so that the rotation center height of the dividing head chuck is the same as the inner hole center of the round flange end of the exhaust pipe, and then use a marking disk to mark the waistlines on both sides of the exhaust pipe that are 90° to the horizontal center waistline;

[0010] 2) Processing the exhaust pipe hexagonal flange end face and the first connection hole

[0011] d. Clamp the exhaust pipe horizontally on the machine tool with the air inlet end facing downward, level the horizontal center waistline, and level the waistlines on both sides so that the waistlines on both sides are perpendicular to the machine tool spindle;

[0012] e. Determine the positioning center of multiple first connection holes at the hexagonal flange end according to the cross center line of the end face of the hexagonal flange end of the exhaust pipe, and run coordinate drilling, expansion, and reaming of multiple first connection holes;

[0013] f. Rough and fine milling of the end face of the hexagonal flange of the exhaust pipe;

[0014] 3) Processing the end face of the exhaust pipe circular flange and the second connection hole

[0015] g. Install the special fixture on the workbench of the digital boring machine, and support the exhaust pipe horizontally on the jack with the air inlet end facing upwards. Fix the hexagonal flange end and the round flange end of the exhaust pipe on the positioning seat and measuring seat of the special fixture respectively, and level the horizontal center waistline;

[0016] h. Assume that the distance from the center of the measuring hole of the measuring seat to the line connecting the center of the end face of the hexagonal flange end of the exhaust pipe and the center of the end face of the circular flange end is a, the center distance between the center of the measuring hole of the measuring seat and the end face of the circular flange end is b, and the distance between the end face of the measuring seat and the end face of the circular flange end is c. Rotate the worktable to align the center position of the measuring hole of the measuring seat. After running the coordinates Xa and Yb, the center position of the measuring hole of the measuring seat is X0 and Y0. Continue to run the coordinates Zc to obtain the final coordinates (X0, Y0, Z0) of the center of the measuring hole of the measuring seat, thereby establishing the workpiece coordinate system;

[0017] i. Coordinate roughing and fine milling of the end face of the circular flange of the exhaust pipe;

[0018] j. Run coordinate drilling to drill multiple second connection holes at the circular flange end of the exhaust pipe.

[0019] The purpose of the present invention can be further achieved by the following technical measures.

[0020] The aforementioned method for processing the mounting surfaces and connecting holes at both ends of the diesel engine exhaust pipe, wherein the special tools in step 3) include a base plate, a positioning seat, a measuring seat, a jack, several pressure plates and several tensioning bolts, the base plate is fixed on the workbench of the digital boring machine, the positioning seat and the measuring seat are respectively fixed at the corresponding positions of the diagonal corners of the base plate, the bottom of the exhaust pipe is supported on the jack on the upper side of the base plate, the inner ends of several pressure plates are symmetrically pressed on the end face of the intake end and tightened by several tensioning bolts, and the outer ends of several pressure plates are supported on corresponding pads.

[0021] The aforementioned method for processing the mounting surfaces and connecting holes at both ends of the diesel engine exhaust pipe is characterized in that the positioning seat is arranged at an angle, and the angle α between the vertical center line of the vertical mounting surface of the positioning seat and the center line of the end face of the measuring seat matches the angle β between the center line of the end face of the hexagonal flange end of the exhaust pipe and the center line of the end face of the circular flange end.

[0022] The present invention uses the mutually perpendicular horizontal center waistline and the waistlines on both sides of the exhaust pipe as the reference, marks the positioning center of the hexagonal flange end face of the exhaust pipe and the first connecting hole, realizes the processing of the hexagonal flange end face and the first connecting hole, and at the same time establishes a workpiece coordinate system through a measuring seat, and realizes the processing of the exhaust pipe circular flange end face and the second connecting hole through running coordinates. Not only is the marking accurate and reliable, the reference is unified and stable, the positioning is accurate, and the consistency of the workpiece size is good, which can effectively ensure the processing accuracy of the workpiece. The method of the present invention can be used when processing such inclined surfaces with a certain angle on both sides on an ordinary digital display boring machine, and has a wide range of applications and good promotion.

[0023] Advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments thereof, which are given by way of example only with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural diagram of a diesel engine exhaust pipe;

[0025] Figure 2 yes Figure 1 A top view of

[0026] Figure 3 It is a structural diagram of the diesel engine exhaust pipe installed on a special fixture;

[0027] Figure 4 yes Figure 3 A top view of

[0028] Figure 5 yes Figure 3 B-axis view after removing part of the fixture. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0030] A method for processing mounting surfaces and connecting holes at both ends of a diesel engine exhaust pipe includes the following steps:

[0031] 1) Fitter marking

[0032] a. Draw the horizontal center waistline of the diesel engine exhaust pipe 1: Figure 2 As shown, the inlet end 30 of the exhaust pipe is supported downwardly and horizontally on the marking table, a wooden strip is driven into the inner hole of the hexagonal flange end 10 of the exhaust pipe, and the outer side surface of the wooden strip is flush with the end surface of the hexagonal flange end 10 of the exhaust pipe; then the hexagonal flange end 10, the round flange end 20 and the inlet end 30 of the exhaust pipe are supported on several adjustable supports (not shown in the figure), and the adjustable supports of the inlet end 30 are manually adjusted to keep the two opposite vertical sides of the hexagonal flange end 10 in a vertical state, and at the same time, the center heights of the inner holes of the hexagonal flange end 10 and the round flange end 20 are measured respectively with a height vernier ruler, and the adjustable supports of the hexagonal flange end 10 and the round flange end 20 are adjusted to make the center heights of the inner holes of the two equal; finally, the height of the marking needle of the marking disk is adjusted to the center height of the inner holes of the hexagonal flange end 10 and the round flange end 20, and the marking disk is moved steadily on the marking platform for one circle, and the horizontal center waistline 1 of the exhaust pipe can be marked;

[0033] When adjusting the center height of the inner hole of the hexagonal flange end 10 and the circular flange end 20, first use the height vernier to measure the highest point position H11 and the highest point position H12 of the inner hole of the hexagonal flange end 10, and take the average value to obtain the center height H1=(H11+H12) / 2 of the center O1 of the inner hole of the hexagonal flange end 10; use the same method to obtain the center height H2 of the inner hole center O2 of the circular flange end. If H1>H2, manually adjust the adjustable support on the lower side of the hexagonal flange end 10 to move the hexagonal flange end 10 down by (H1-H2) / 2, and at the same time manually adjust the adjustable support on the lower side of the circular flange end 20 to raise the circular flange end 20 by (H1-H2) / 2, and measure with the height vernier while adjusting until the inner hole centers of the hexagonal flange end 10 and the circular flange end 20 are at the same height.

[0034] b. Draw the cross center line of the 10 end face of the hexagonal flange end of the exhaust pipe on the wooden strip;

[0035] like Figure 2 As shown, with the two intersection points O3 and O4 of the horizontal center waistline 1 and the inner hole circumference of the hexagonal flange end 10 as the center, circles are drawn with a radius greater than the radius of the inner hole of the hexagonal flange end 10. The line connecting the intersection points of the two circles is the vertical centerline of the end face of the hexagonal flange end 10 of the exhaust pipe, and the horizontal center waistline 1 is its horizontal centerline.

[0036] c. Mark the waistline 2 on both sides of the exhaust pipe: Clamp the round flange end 20 of the exhaust pipe with a dividing head, level the horizontal center waistline 1, and then rotate the dividing head 90°. At this time, the exhaust pipe turns to Figure 1 In the state shown, use a height vernier to measure the rotation center height of the indexing head chuck and adjust it through the adjustable support to make the rotation center height of the indexing head chuck equal to the inner hole center of the circular flange end 20 of the exhaust pipe. Then adjust the height of the scribing needle of the scribing disk to the rotation center height of the indexing head chuck, and move the scribing disk smoothly on the scribing platform for one circle, so that the waist lines 2 on both sides of the exhaust pipe that are 90° to the horizontal center waist line 1 can be drawn, as shown in FIG. Figure 1 As shown;

[0037] 2) Processing the end surface of the hexagonal flange end 10 of the exhaust pipe and the first connecting hole 101 thereon

[0038] d. Clamp the exhaust pipe with the air inlet end 30 facing downward horizontally on the machine tool, level the horizontal center waistline 1, and align the waistlines 2 on both sides so that the waistlines 2 on both sides are perpendicular to the machine tool spindle;

[0039] e. Determine the positioning center of the plurality of first connection holes 101 of the hexagonal flange end 10 according to the cross center line of the end face of the exhaust pipe hexagonal flange end 10, and run coordinate drilling, expansion, and reaming of the plurality of first connection holes 101;

[0040] f. Rough and fine milling of the end face of the hexagonal flange of the exhaust pipe;

[0041] 3) Processing the end surface of the exhaust pipe circular flange end 20 and the second connecting hole 201

[0042] g. Figure 3 As shown, a special fixture is installed on the workbench of a digital boring machine, and the inlet end 30 of the exhaust pipe is supported upward and horizontally on a jack 24, and the hexagonal flange end 10 and the round flange end 20 of the exhaust pipe are respectively fixed on the positioning seat 22 and the measuring seat 23 of the special fixture, and the horizontal center waistline 1 is leveled;

[0043] The special tool 2 includes a base plate 21, a positioning seat 22, a measuring seat 23, a jack 24, two pressing plates 25 and two tightening bolts 26. The base plate 21 is fixed on the workbench of the digital boring machine by fasteners. The positioning seat 22 and the measuring seat 23 are respectively fixed at the corresponding positions of the diagonal of the base plate 21. The bottom of the exhaust pipe is supported on the jack 24 on the upper side of the base plate 21. The inner ends of the two pressing plates 25 are symmetrically pressed on the end face of the intake end 30 and tightened by two tightening bolts 26. The outer ends of the two pressing plates 25 are supported on the corresponding pads 27. The positioning seat 22 is tilted, and the angle α between the center line of the vertical mounting surface 221 of the positioning seat 22 and the center line of the end face of the measuring seat 23 matches the angle β between the center line of the end face of the hexagonal flange end of the exhaust pipe and the center line of the end face of the circular flange end.

[0044] h. Figure 4 and Figure 5 As shown, let the distance from the center of the measuring hole of the measuring seat 23 to the line connecting the center of the end face of the hexagonal flange end 10 of the exhaust pipe and the center of the end face of the circular flange end 20 be a, the distance between the center of the measuring hole of the measuring seat 23 and the end face of the circular flange end 20 be b, and the distance between the end face of the measuring seat 23 and the end face of the circular flange end 20 be c. Rotate the worktable to find the center position of the measuring hole of the measuring seat 23. After running the coordinates Xa and Yb, the center position of the measuring hole of the measuring seat 23 is X0 and Y0. Continue to run the coordinates Zc to obtain the final coordinates (X0, Y0, Z0) of the center of the measuring hole of the measuring seat 23, thereby establishing the workpiece coordinate system.

[0045] i. Coordinate roughing and fine milling of the end face of the exhaust pipe circular flange end 20;

[0046] j. Drill multiple second connection holes 201 on the circular flange end 20 of the exhaust pipe.

[0047] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solutions formed by equivalent replacement or equivalent transformation shall fall within the protection scope required by the present invention.

Claims

1. A method for processing the mounting surfaces and connecting holes at both ends of a diesel engine exhaust pipe. It is characterized in that The following steps are involved: 1) Fitter marking a. Mark the horizontal center waistline of the diesel engine exhaust pipe: support the exhaust pipe intake end horizontally on the marking table with the intake end facing downward, drive a wooden strip into the inner hole of the exhaust pipe hexagonal flange end, and make the outer side of the wooden strip flush with the end face of the hexagonal flange end of the exhaust pipe; then support the hexagonal flange end, round flange end and intake end of the exhaust pipe on several adjustable supports respectively, manually adjust the adjustable support of the intake end to keep the relatively vertical side of the hexagonal flange end in a vertical state, and use a height vernier ruler to measure the center height of the inner hole of the hexagonal flange end and the round flange end respectively, adjust the adjustable supports of the hexagonal flange end and the round flange end to make the center height of the inner hole of the two equal; finally, mark the horizontal center waistline of the exhaust pipe with a marking disk; b. Draw the cross center line of the end face of the hexagonal flange of the exhaust pipe on the wooden strip; c. Mark the waistline on both sides of the exhaust pipe: Clamp the round flange end of the exhaust pipe with a dividing head, level the horizontal center waistline, then rotate the dividing head 90°, measure the rotation center height of the dividing head chuck with a height vernier ruler, and adjust it through the adjustable support so that the rotation center height of the dividing head chuck is the same as the inner hole center of the round flange end of the exhaust pipe, and then use a marking disk to mark the waistlines on both sides of the exhaust pipe that are 90° to the horizontal center waistline; 2) Processing the exhaust pipe hexagonal flange end face and the first connection hole d. Clamp the exhaust pipe horizontally on the machine tool with the air inlet end facing downward, level the horizontal center waistline, and level the waistlines on both sides so that the waistlines on both sides are perpendicular to the machine tool spindle; e. Determine the positioning center of multiple first connection holes at the hexagonal flange end according to the cross center line of the end face of the hexagonal flange end of the exhaust pipe, and run coordinate drilling, expansion, and reaming of multiple first connection holes; f. Rough and fine milling of the end face of the hexagonal flange of the exhaust pipe; 3) Processing the end face of the exhaust pipe circular flange and the second connection hole g. Install the special fixture on the workbench of the digital boring machine, and support the exhaust pipe horizontally on the jack with the air inlet end facing upwards. Fix the hexagonal flange end and the round flange end of the exhaust pipe on the positioning seat and measuring seat of the special fixture respectively, and level the horizontal center waistline; h. Assume that the distance from the center of the measuring hole of the measuring seat to the line connecting the center of the end face of the hexagonal flange end of the exhaust pipe and the center of the end face of the circular flange end is a, the center distance between the center of the measuring hole of the measuring seat and the end face of the circular flange end is b, and the distance between the end face of the measuring seat and the end face of the circular flange end is c. Rotate the worktable to align the center position of the measuring hole of the measuring seat. After running the coordinates Xa and Yb, the center position of the measuring hole of the measuring seat is X0 and Y0. Continue to run the coordinates Zc to obtain the final coordinates (X0, Y0, Z0) of the center of the measuring hole of the measuring seat, thereby establishing the workpiece coordinate system; i. Coordinate roughing and fine milling of the end face of the circular flange of the exhaust pipe; j. Run coordinate drilling to drill multiple second connection holes at the circular flange end of the exhaust pipe.

2. The method for processing the mounting surfaces and connecting holes at both ends of the diesel engine exhaust pipe as claimed in claim 1, Features: The special tools in step 3) include a base plate, a positioning seat, a measuring seat, a jack, several pressure plates and several tightening bolts. The base plate is fixed on the workbench of the digital boring machine. The positioning seat and the measuring seat are respectively fixed at the corresponding positions of the diagonal corners of the base plate. The bottom of the exhaust pipe is supported on the jack on the upper side of the base plate. The inner ends of several pressure plates are symmetrically pressed on the end face of the intake end and tightened by several tightening bolts. The outer ends of several pressure plates are supported on corresponding pads.

3. The method for processing the mounting surfaces and connecting holes at both ends of the diesel engine exhaust pipe as claimed in claim 2, Features: The positioning seat is tilted, and the angle α between the vertical center line of the positioning seat vertical installation surface and the center line of the measuring seat end face matches the angle β between the center line of the exhaust pipe hexagonal flange end face and the center line of the circular flange end face.

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