A deep hole machining process

Abstract

The application discloses a deep hole machining process and belongs to the technical field of deep hole machining. The deep hole machining process comprises the following steps: ensuring that all required drill bits in a hole machining group are perpendicular to the surface of a workpiece, and then enabling the drill bits to contact the workpiece through extension and contraction, so that the drill bits can be stably and safely embedded into the workpiece when rotating. The application solves the problem that the existing deep hole machining method can only segmentally drill holes through drill bits during machining, and cannot process deep holes with large diameters at low cost. The application realizes segmented drilling and reaming by two steps, i.e., first drilling a pilot hole, then drilling a first enlarged hole along the pilot hole, and finally reaming the hole by deeply inserting a cutting tool used for reaming into the first enlarged hole. The segmented drilling and reaming can avoid drill bit breakage and high temperature discharge failure caused by long-distance and large-diameter reaming.

Description

Technical Field

[0001] The present invention relates to the technical field of deep hole processing, in particular to a deep hole processing technology. Background Art

[0002] Deep hole machining is a machining technology for holes with a length-to-diameter ratio greater than 6 cm. It aims to perform precise and continuous drilling operations inside the material through specific process methods. This machining method requires high precision control, effective chip evacuation mechanisms, and appropriate coolant supply to ensure tool stability and hole wall quality during machining.

[0003] A Chinese patent with publication number CN102059366B discloses a deep hole processing method with variable drilling depth and chip breaking and removal, which includes the following steps: specifying deep hole drilling variables, assigning values ​​to the variables involved in deep hole drilling, entering the next step if the values ​​are correct, and entering the alarm step if the values ​​are incorrect, and reassigning values. The specified variables include a safety height, a feed rate, a first hole depth, a drilling start position, a drilling end position, a drilling depth reduction ratio, and a minimum drilling depth. The deep hole drilling depth is divided into several sections, and each section combines chip breaking and chip removal actions. Chip breaking is used within a certain drilling depth range, and chip removal is performed beyond this range, thereby keeping the iron chips discharged smoothly at all times, improving efficiency, and ensuring drilling safety.

[0004] The deep hole processing method of the above patent is processed in sections during the processing process, but when drilling is only performed in sections by the drill bit, it is impossible to directly drill large-diameter deep holes using the method in the comparative document. There are many restrictions when drilling large-diameter deep holes. Directly drilling large-diameter holes requires installing the corresponding diameter drilling holes each time, which is more cumbersome and complicated. Directly drilling large-diameter holes will cause high-temperature damage to the drill bit, resulting in reduced safety during processing. Damage to the drill bit will also affect the cost of deep hole processing. Summary of the Invention

[0005] The purpose of the present invention is to provide a deep hole processing technology, which performs drilling and reaming through multiple stages. The drilling is divided into two steps. First, a guide hole is drilled, and the first enlarged hole is drilled along the guide hole. The cutting tool used for reaming is inserted into the first enlarged hole to achieve the final reaming. The drilling and reaming are performed in stages, which can avoid drill bit breakage caused by long-distance and large-diameter reaming and the inability to discharge high temperature, thereby solving the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a deep hole processing process, comprising the following steps:

[0007] Step 1: In order to ensure the stability and accuracy of the workpiece during the drilling process, the clamping structure surrounds the workpiece to be drilled and clamps it. A suitable drill bit is selected to form a hole processing group to ensure that the workpiece will not move or vibrate due to external force and centrifugal force generated by rotation during the processing. The clamping structure clamps and fixes the workpiece, and can also effectively prevent processing errors and possible mechanical damage caused by workpiece displacement, according to the material of the workpiece and the size requirements of the hole;

[0008] Step 2: Fix the appropriate hole processing group selected in Step 1 to the CNC machine tool, ensuring that all required drill bits in the hole processing group are perpendicular to the workpiece surface. The drill bits can then be extended and retracted to contact the workpiece. The vertical distribution allows the drill bits to be stably and safely embedded in the workpiece during rotation.

[0009] Step 3: Start the telescopic structure in the CNC machine tool to push the first drill bit in the hole processing group. The drill bit is independently driven by the corresponding motor to rotate. The push of the telescopic structure causes the drill bit in the rotating state to contact the workpiece clamped in step 1. The twist drill can realize the processing of the fixed workpiece guide hole. The drilling of the twist drill can ensure the straightness and stability of the subsequent micro-drilling.

[0010] In step 4, the drill bit drills a hole in step 3 and forms a guide hole in the workpiece to ensure the straightness and stability during subsequent micro-drilling. The CNC machine tool adjusts the drill bits in the hole processing group so that the center position of the second drill bit is aligned with the center position of the guide hole formed in step 3. Subsequently, the CNC machine tool and the motor are started to move the adjusted drill bit toward the guide hole. The adjusted drill bit is the same as the first drill bit in step 3, so that the second drill bit drills along the guide hole. During the drilling process in step 4, the coolant is pumped by the pump and discharged at the cutting position to actively reduce the temperature of the micro-drilling and workpiece drilling positions. At the same time, attention should be paid to the discharge of drilling debris to avoid blockage caused by drilling debris affecting drilling.

[0011] Step 5. Adjust the coolant discharge position to align it with the middle position between the deep hole diameter processing edge and the hole edge generated by the drill bit rotation in step 4, so that the coolant can cool the subsequent hole expansion position. The cooling liquid can be sprayed at the nearest position of the heat each time, so that in the subsequent gradual hole expansion process, the cooling liquid can be sprayed at the nearest position of the heat each time, thereby improving the safety of subsequent deep hole processing;

[0012] Step six, the numerical control machine tool retracts the drill bit in step four and adjusts the hole processing group, deviates the third drill bit from the side of the hole produced by the drill bit in step four, approaches the inner wall of the hole produced by the drill bit, and rotates the workpiece with the center of the drill hole by the motor through the clamping structure, continuously moves and expands the hole wall of the cutting tool, and further expands the hole after single expansion. Further in-depth and repeated expansion until the expansion depth is the same as the depth of the hole drilled by the drill bit in the previous step four;

[0013] Step seven, calculate whether the repeated drilling depth of step three is stacked to the length of the deep hole. When the repeated drilling depth of step three is not stacked to the required length, return to step three and repeat the processing of the guide hole. When the repeated drilling depth of step three reaches the required length, there is no need to return to step three and repeat the processing of the guide hole, and step eight is implemented.

[0014] Step eight, slowly retract all drill bits, repeatedly fit the inner wall of the hole by the third drill bit, rotate the workpiece according to the center of the hole, and continuously push the third drill bit by the telescopic device, so that the third drill bit is embedded in the deep hole at one time, avoiding protrusions in the deep hole due to multiple segmented polishing, and avoiding the effect of the finished product and subsequent use.

[0015] Step nine, slowly retract the whole hole processing group, close the machine tool, finally clean the debris inside the deep hole of the workpiece, and finally measure the diameter and depth of the hole to ensure that the design requirements are met.

[0016] Preferably, the hole processing group in step one is composed of a twist drill, a micro drill and a cutting tool. The twist drill corresponds to the first drill bit in step three, the micro drill corresponds to the second drill bit in step four, and the cutting tool corresponds to the third drill bit in step six.

[0017] Preferably, the diameter of the twist drill in step three can be selected in the range of one millimeter to four millimeters. A small hole can be punched in the middle of the subsequent hole expansion position by a twist drill with a diameter of one millimeter to four millimeters, so that the subsequent hole punching follows the small hole produced by the rotation of the twist drill. A small guide hole can be used to avoid subsequent hole punching from deviating.

[0018] Preferably, the diameter of the micro drill in step four is less than six centimeters and greater than four centimeters. The rotation of the micro drill can expand the guide hole, so that the inner position of the guide hole can be inserted into the cutting tool.

[0019] Preferably, the cutting tool in step six is rectangular, and the width of the cutting tool is less than four centimeters. A cutting tool with a width of less than four centimeters can make the cutting tool penetrate the hole produced by the rotation of the twist drill and the micro drill.

[0020] Preferably, the length of the hole produced by the rotation of the micro drill in step four is less than six centimeters.

[0021] Preferably, the depth of the single hole expansion of the cutting knife in step six is ​​the same as the length of the cutting knife itself, so that the entire length of the cutting knife can be used for friction to achieve cutting, which is convenient for improving the utilization rate of the cutting knife and reducing the frequency of use of the cutting knife.

[0022] Preferably, in step six, after the first reaming, the cutting tool needs to be further expanded again. When the penetration distance is shorter than the length of the cutting tool, the cutting tool can be pushed and penetrated to the maximum length that can be entered. The chips of the last cutting tool can be flexibly adjusted to avoid excessive embedding of the cutting tool, which may cause damage to both the cutting tool and the workpiece.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention divides the entire depth into several sections for drilling and processing during deep hole processing. The processing length of each section is six centimeters, which can convert deep hole processing into ordinary drilling. Drilling in sections can directly avoid the depth of a single drilling being longer than six centimeters, avoid the impact of deeper drilling requirements on heat discharge and drilling debris discharge, and avoid damage to the drill bit caused by deeper drilling. On the other hand, in the process of segmented drilling, since the diameter of some holes is much larger than the diameter of the drill bit, frequent replacement of the drill bit and matching of the appropriate drill bit affect the efficiency of deep hole processing. Therefore, when drilling in sections, each time a hole is drilled for a workpiece within a length range, the center point of the drilling position is first marked. A guide hole with the same length as the segment is expanded along the guide hole to form a hole that the cutting tool can penetrate. Subsequently, through the continuous lateral movement of the cutting tool and the rotation of the workpiece, the hole expansion of any diameter can be achieved. It is worth mentioning that during the hole expansion process, the depth of the hole expansion inside the guide hole is the same as the length of the cutting tool, and the deeper position inside will not be cut. The external coolant can be sprayed at the closest position each time to synchronously cool the cutting and cut parties. The superimposed depth of multiple hole expansions reaches the required depth of the deep hole to complete a single deep hole processing. The cooling is efficient and the debris discharge efficiency is high. The drilling does not need to be continuously rotated due to the long embedding depth and may cause damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flow chart of the deep hole processing process of the present invention;

[0026] Figure 2 It is a schematic diagram of the deep hole processing steps of the present invention. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to specific embodiments.

[0028] like Figure 1 and Figure 2As shown, a deep hole processing process of this embodiment includes the following steps:

[0029] Step 1: To ensure the stability and accuracy of the workpiece during the drilling process, a clamping structure surrounds the workpiece to be drilled to ensure that the workpiece does not move or vibrate due to external forces and centrifugal forces generated by rotation during the processing. In addition, the workpiece is clamped and fixed to prevent processing errors and possible mechanical damage caused by workpiece displacement;

[0030] On the other hand, the clamping structure can clamp and fix the workpiece, and can also effectively prevent processing errors and possible mechanical damage caused by workpiece displacement, according to the material of the workpiece and the size requirements of the hole;

[0031] Among them, a suitable twist drill, micro drill and cutting tool are selected to form a hole processing group. The diameter of the twist drill can be selected in the range of one millimeter to four millimeters, and the diameter of the micro drill is less than six centimeters and greater than four centimeters. Finally, the width of the cutting tool is less than four centimeters. The cutting tool less than four centimeters can facilitate the cutting tool to penetrate into the hole formed by the rotation of the twist drill and micro drill, and facilitate the subsequent expansion of the hole by the cutting tool and fitting the inner wall of the hole;

[0032] Step 2: Install the appropriate hole processing group selected in step 1 on the CNC machine tool, ensuring that all required drill bits in the hole processing group are perpendicular to the workpiece surface. This can be achieved by changing the relative position of the hole processing group.

[0033] Maintaining the perpendicularity between the drill bit and the workpiece surface allows the drill bit to contact the workpiece by subsequent extension and retraction. The vertical distribution allows the drill bit to be stably and safely embedded in the workpiece.

[0034] Step 3: Determine the drilling position of the workpiece clamped in Step 1, activate the telescopic structure in the CNC machine tool to push the twist drill in the hole processing group, and activate the motor in the CNC machine tool to independently drive the twist drill to rotate. As the telescopic structure pushes, the twist drill in the rotating state contacts the clamped workpiece;

[0035] The twist drill can be used to process the guide hole of the fixed workpiece, and the drilling by the twist drill can ensure the straightness and stability of the subsequent micro-drilling;

[0036] After completing the installation of the hole processing group, start the telescopic structure in the CNC machine tool to push the first drill bit in the hole processing group. The drill bit will be driven by an independent motor to rotate. The advantage of this is that the drill bit can remain stably embedded in the workpiece during rotation, avoiding errors caused by the movement or rotation of the workpiece.

[0037] Step 4: After the twist drill processes the guide hole, it is taken out, and the CNC machine tool adjusts the hole processing group so that the center position of the micro drill is aligned with the center position of the guide hole. The CNC machine tool and the motor are started to move the micro drill toward the guide hole, and the micro drill is used to drill along the guide hole;

[0038] Among them, micro-drilling produces holes with a length of less than six centimeters;

[0039] In addition, the micro drill is slowly pushed and inserted into the pilot hole;

[0040] During the rotation and cutting process, the coolant is pumped out by the pump and discharged at the cutting position, actively reducing the temperature of the micro-drilling and workpiece drilling positions;

[0041] At the same time, attention should be paid to the discharge of drilling debris to avoid blockage caused by drilling debris.

[0042] Use a twist drill to machine the workpiece to secure the pilot hole. This process will allow the drill bit to contact the workpiece clamped in step 1 to ensure its stability and safety during rotation.

[0043] Step 5: Adjust the coolant discharge position so that it is aligned with the middle position between the edge of the deep hole processing and the edge of the hole produced by the micro drilling in step 4;

[0044] The pump continuously extracts and cools the subsequent hole expansion position, so that during the subsequent gradual hole expansion process, the cooling liquid can be sprayed at the nearest hot position each time, improving the safety of subsequent deep hole processing;

[0045] Step 6: Using a CNC machine tool to retract the micro-drill and adjust the hole processing group, the cutting tool in the hole processing group deviates from the side of the hole generated by the micro-drill in step 4, deviates from and approaches the inner wall of the hole generated by the micro-drill, and starts the motor corresponding to the clamping structure so that the motor drives the workpiece to rotate through the clamping structure, and the center of the rotation overlaps with the center of the hole generated by the micro-drill in step 4. The cutting tool continues to move toward the inner wall of the hole generated by the micro-drill and expands the hole;

[0046] The depth of a single hole expansion is the same as the length of the cutting tool;

[0047] After a single hole expansion, the cutting blade is pushed deeper by the telescopic device, and the hole expansion is repeated until the cumulative hole expansion depth is the same as the depth of the micro-drilling in the previous step 4, and the debris is cleaned after the hole expansion is completed;

[0048] After the first round of hole enlargement, the drill bits in the hole processing group are adjusted so that the center of the second drill bit is aligned with the center of the guide hole formed in the first step. Then, the CNC machine tool and the motor are started to move the adjusted drill bit toward the guide hole for the second round of hole enlargement.

[0049] After the second hole expansion, adjust the coolant discharge position so that it is aligned with the middle position between the edge of the deep hole diameter and the guide hole formed in the second step. This can effectively reduce the temperature and improve the safety of the processing process.

[0050] It should be noted that the distance the cutter penetrates after the first reaming is the same as the length of the cutter. However, when the penetration distance is shorter than the length of the cutter, the cutter can be pushed and penetrated to the maximum length that can be entered.

[0051] After completing step 6, in step 7, calculate whether the repeated drilling depth of the twist drill is superimposed on the deep hole length. After completing the required length of the deep hole, there is no need to return to step 3 and repeat the cutting of the pilot hole, and step 8 is carried out;

[0052] After completing step six several times and calculating that the repeated drilling depth of the twist drill has not reached the required length, return to step three and perform chip cutting of the pilot hole again;

[0053] Step 8: When the cumulative length of the hole reaches the required depth, slowly withdraw all the drill bits, and finally use the cutting tool to repeatedly fit the inner wall of the hole, repeatedly rotate the workpiece according to the center of the hole, and continuously push the cutting tool with the telescopic device, so that the cutting tool is embedded in the deep hole at one time;

[0054] After calculating the repeated drilling depth in step 3, begin gradually increasing the hole depth and width. Start by enlarging the hole with a twist drill, then switch to a micro drill. After each enlargement, use a cutting tool to further increase the hole depth and width.

[0055] Avoid protrusions inside deep holes due to multiple segmented grinding, which will affect the effect of the finished product and subsequent use;

[0056] Step 9. Slowly exit the whole hole processing group, turn off the machine tool, and finally clean the debris inside the deep hole of the workpiece. Finally, measure the diameter and depth of the hole to ensure that it meets the design requirements.

[0057] Working principle: The workpiece is clamped and the drill bit is fixed on the CNC machine tool. The twist drill is first pushed by telescoping, and the twist drill is independently driven to rotate by the motor to drill and form a guide hole. The micro drill further drills along the guide hole to expand the hole spacing, and the temperature during drilling is reduced by coolant during the drilling process. After drilling, the drilling position is adjusted to align with the middle position between the deep hole diameter processing edge and the hole edge generated by the micro drill rotation. The cutting tool is penetrated into the previously drilled hole, deviated from the center position and close to the inner wall of the hole. The motor drives the workpiece to rotate with the center of the drilling circle, and the cutting tool continues to move toward the inner wall of the drill hole and expand the hole. After a single expansion, the cutting tool is pushed deeper, further deepened and expanded again until the expansion depth is the same as the depth of the last micro drill drilling. When the depth of the entire expansion does not reach the required length, the guide hole and subsequent expansion steps are repeated until the length of the entire expansion meets the requirements of the deep hole length.

[0058] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0059] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A deep hole processing process, characterized in that: The steps include: Step 1: The clamping structure surrounds and clamps the workpiece to be drilled, and a suitable drill bit is selected to form a hole processing group; Step 2: Fix the appropriate hole processing group selected in Step 1 to the CNC machine tool, ensuring that all required drill bits in the hole processing group are perpendicular to the workpiece surface. Then, the drill bits are extended and retracted to contact the workpiece. The vertical distribution allows the drill bits to be stably and safely embedded in the workpiece during rotation. Step 3: Start the telescopic structure in the CNC machine tool to push the twist drill in the hole processing group. The twist drill is independently driven by the corresponding motor to rotate. The push of the telescopic structure causes the drill bit in the rotating state to contact the workpiece clamped in step 1. In step 4, the twist drill in step 3 drills a hole and forms a guide hole in the workpiece to ensure the straightness and stability of the subsequent micro-drill drilling. The CNC machine tool adjusts the drill bit in the hole processing group so that the center position of the micro-drill is aligned with the center position of the guide hole formed in step 3. Subsequently, the CNC machine tool and the motor are started to move the adjusted micro-drill toward the guide hole, so that the micro-drill drills along the guide hole; Step 5: Adjust the coolant discharge position to align it with the middle position between the deep hole diameter processing edge and the edge of the hole produced by micro-drilling in step 4, so that the coolant can cool the subsequent hole expansion position; Step 6: The CNC machine tool retracts the micro-drill in step 4 and adjusts the hole processing group, deviating the cutting tool from the side of the hole generated by the micro-drill in step 4 and approaching the inner wall of the hole generated by the micro-drill. The motor drives the workpiece to rotate about the center of the hole generated by the micro-drill through the clamping structure. The cutting tool continues to move toward the inner wall of the hole and expands the hole. After a single expansion, the cutting tool is pushed deeper and the expansion is repeated; Step 7: Calculate whether the repeated drilling depths of the twist drill in step 3 are added up to the deep hole length. If the added repeated drilling depths of the twist drill in step 3 do not reach the required length, return to step 3 and perform the pilot hole processing again. If the repeated drilling depths of step 3 reach the required length, there is no need to return to step 3 and repeat the pilot hole processing, and step 8 is performed. Step 8. Slowly withdraw all the drill bits, repeatedly fit the inner wall of the hole with the cutting blade, rotate the workpiece according to the center of the hole, and continuously push the cutting blade with the telescopic device so that the cutting blade is embedded in the deep hole at one time; Step 9. Slowly exit the whole hole processing group, turn off the machine tool, and finally clean the debris inside the deep hole of the workpiece. Finally, measure the diameter and depth of the hole to ensure that it meets the design requirements.

2. A deep hole processing process according to claim 1, characterized in that: The diameter of the twist drill in step 3 may be selected in a range from 1 mm to 4 mm.

3. The deep hole processing process according to claim 1, characterized in that: The diameter of the micro drill in step 4 is less than six centimeters and greater than four centimeters.

4. The deep hole processing process according to claim 1, characterized in that: In step six, the cutting blade is rectangular and has a width of less than four centimeters. The cutting blade having a width less than four centimeters can penetrate deeply into the hole generated by the twist drill and the micro drill.

5. The deep hole processing process according to claim 1, characterized in that: The length of the hole generated by the rotation of the micro drill in step 4 is less than six centimeters.

6. The deep hole processing process according to claim 1, characterized in that: The depth of the hole enlarged by the cutting tool in step 6 is the same as the length of the cutting tool itself.

7. The deep hole processing process according to claim 1, characterized in that: In step six, after the first reaming, the cutting tool needs to be further expanded to further expand the hole. When the penetration distance is shorter than the length of the cutting tool, the cutting tool can be pushed and penetrated to the maximum length that can be entered.

8. The deep hole machining process according to claim 1, characterized in that: During the drilling process in step 4, the coolant is pumped out by a pump and discharged toward the cutting position, actively reducing the temperature of the micro-drilling and workpiece drilling positions.

9. The deep hole machining process according to claim 1, characterized in that: Repeat the hole enlargement in step 6 until the cumulative hole enlargement depth is the same as the depth of the micro-drilling in the previous step 4.

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