阅读说明：本技术 一种履带起重机履带板的制造工艺 (Manufacturing process of crawler plate of crawler crane ) 是由 王文明 陈红华 董学礼 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种履带起重机履带板的制造工艺,其包括模具制造工序、原材料熔炼工序、浇筑工序、浇筑后处理工序、热处理预处理工序、热处理工序、热处理后处理工序及末处理工序。本发明具有提高履带板表面耐磨性能的效果。(The invention relates to a manufacturing process of a crawler plate of a crawler crane, which comprises a die manufacturing process, a raw material smelting process, a pouring post-treatment process, a heat treatment pretreatment process, a heat treatment post-treatment process and a final treatment process. The invention has the effect of improving the surface wear resistance of the track shoe.)

1. The manufacturing process of the crawler plate of the crawler crane is characterized by comprising the following steps of: comprises the following steps of (a) carrying out,

a mold manufacturing process of manufacturing and forming an upper mold and a lower mold using the sand and the mold shell, manufacturing an inner core using furan resin sand, then correspondingly installing the inner core into the lower mold, and closing the upper mold and the lower mold;

a raw material smelting step of smelting the recovered scrap iron raw material in an environment of 1530-1550 ℃ to obtain molten iron;

pouring, namely pouring the molten iron obtained in the raw material smelting step into a pouring hole of an upper die, heating the molten iron to 1620-1640 ℃ before pouring, preserving the heat for 4-10 hours after the molten iron pouring is finished, opening the upper die after the heat preservation is finished, cooling and solidifying for 3-5 minutes, and forming a track plate original piece with a fixed shape after the molten iron;

a pouring post-treatment process, namely removing large blocks of residual gravels on the surface of the original crawler plate, then placing the original crawler plate into a shot blasting machine for rough shot blasting, wherein shot used in the rough shot blasting is 2-3 mm in diameter, shot blasting time is 8-12 minutes, and then cutting and removing runners, risers and surface burrs generated in the pouring process in a thermal cutting mode;

a heat treatment pretreatment process, wherein the surface of the original creeper tread is subjected to rough grinding and fine grinding, redundant burrs on the surface of the original creeper tread are further removed, the surface defect of the original creeper tread is inspected after the fine grinding is finished, the surface of the original creeper tread is required to be repaired when the defect does not meet the inspection requirement, the original creeper tread is required to be repaired, the original creeper tread cannot be repaired, and the original creeper tread is required to be marked as a waste part;

a heat treatment process, namely sequentially carrying out a normalizing process, a quenching and tempering process and a surface quenching process on the original crawler plate, carrying out strength inspection after the treatment is finished, and obtaining a semi-finished crawler plate after the strength inspection is passed;

a heat treatment post-treatment process, wherein a dead head on the surface of a semi-finished product of the crawler plate is subjected to finish milling, and then finish shot blasting is performed, wherein the diameter of a shot used in the finish shot blasting is 1.2-1.5 mm, and the shot blasting time is 14-18 minutes; and the number of the first and second groups,

and a final treatment process, namely inspecting the surface defects and the internal defects of the semi-finished product of the track plate, coating after the inspection is finished, and then warehousing and storing.

2. The process of manufacturing a crawler belt shoe for a crawler crane according to claim 1, wherein: in the heat treatment process, the target temperature of the normalizing process is 880-920 ℃, the time of the normalizing process is 9-13 hours, and after the normalizing process is finished, the track shoe original is cooled to 300 ℃ and then the quenching and tempering process is carried out.

3. The process of manufacturing a crawler belt shoe for a crawler crane according to claim 2, wherein: in the normalizing treatment procedure, the used equipment is a high-temperature heat treatment furnace, the first 6-8 hours are a heating process, and the temperature in the high-temperature heat treatment furnace is uniformly raised to the target temperature of the normalizing treatment procedure in the period;

the last 3-5 hours is a heat preservation process, the temperature in the high-temperature heat treatment furnace is kept stable in the period, and the difference between the highest temperature and the lowest temperature in the period is not more than 20 ℃.

4. A process for manufacturing a crawler belt shoe for a crawler crane according to claim 3, wherein: the conditioning treatment comprises a heating treatment process, an integral quenching treatment process and a high-temperature tempering treatment process which are sequentially carried out, wherein the target temperature of the heating treatment process is the same as that of the normalizing treatment process, the heating process of the heating treatment process is the same as that of the normalizing treatment process, and the heat preservation process of the heating treatment process is shortened by 1 hour compared with that of the normalizing treatment process.

5. The process of manufacturing a crawler belt shoe for a crawler crane according to claim 4, wherein: in the whole quenching treatment process, the adopted quenching liquid is industrial salt water with the mass concentration of 8-10%, and the original parts of the track plate after the heating treatment process need to be transferred within 30-40 seconds and immersed into the quenching liquid to finish quenching.

6. The process of manufacturing a crawler crane track shoe according to claim 5, wherein: the target temperature of the high-temperature tempering treatment process is 550-650 ℃, the original crawler plate is uniformly heated for 3-4 hours to reach the target temperature of the high-temperature tempering treatment process, then the temperature is maintained for 3-5 hours, the original crawler plate is cooled by adopting a water cooling mode after the temperature is maintained, and the target temperature of the temperature is 100-150 ℃.

7. The process of manufacturing a crawler belt shoe for a crawler crane according to claim 6, wherein: the surface quenching treatment process is carried out by special surface quenching equipment, the surface quenching equipment heats the designated area of the surface of the original crawler plate in an induction heating mode, the target temperature of the surface quenching treatment process is 900-.

8. The process of manufacturing a crawler crane track shoe according to claim 7, wherein: after the surface quenching treatment process is finished, low-temperature tempering treatment is carried out on the original crawler plate, the target temperature of the low-temperature tempering treatment is 180-220 ℃, and the time of the low-temperature tempering treatment is 4-5 hours.

Technical Field

The invention relates to the field of manufacture of track shoes, in particular to a process for manufacturing a track shoe of a crawler crane.

Background

The crawler crane is a self-propelled crane for courage of high-rise building construction, the bottom of the crawler crane realizes the movement of the crane through a crawler structure, the crawler grounding area is large, the trafficability characteristic is good, the crawler crane is more adaptive when facing various complex terrains and can walk with loads, great convenience is provided for various operations such as material carrying in industries such as buildings, petroleum, chemical engineering, electric power and traffic, and the working efficiency is effectively improved. In a crawler crane, a track shoe forms one of important structures of a crane ground, the crawler crane has a large self weight, and a heavy load needs to be additionally loaded during operation, so that the manufacture of the track shoe with rigid strength is an important guarantee that the crawler crane can complete the lifting function of the crawler crane.

In the prior art, a Chinese patent with publication number CN1270238A discloses a low-alloy austempered steel track shoe and a heat treatment method thereof, wherein the metallographic structure of the track shoe is bainite and austenite, the invention adopts a low-alloy steel mainly containing chromium, manganese and silicon, isothermal quenching and a heat treatment process of cooling in air, and the metallographic structure of the bainite and the austenite is finally obtained, and the metallographic structure has reasonable strength, toughness and hardness.

The above prior art solutions have the following drawbacks: in the process of reproducing the technical scheme of the invention, the inventor finds that the prior art has the following problem that the wear resistance of the surface of the final finished track shoe is insufficient, and the use requirement of the track shoe in the crawler crane in practical application cannot be met.

Disclosure of Invention

The invention aims to provide a manufacturing process of a crawler plate of a crawler crane, which has the advantage of improving the surface wear resistance of the crawler plate.

The technical purpose of the invention is realized by the following technical scheme:

a manufacturing process of a crawler plate of a crawler crane comprises the following steps,

a mold manufacturing process of manufacturing and forming an upper mold and a lower mold using the sand and the mold shell, manufacturing an inner core using furan resin sand, then correspondingly installing the inner core into the lower mold, and closing the upper mold and the lower mold;

a raw material smelting step of smelting the recovered scrap iron raw material in an environment of 1530-1550 ℃ to obtain molten iron;

pouring, namely pouring the molten iron obtained in the raw material smelting step into a pouring hole of an upper die, heating the molten iron to 1620-1640 ℃ before pouring, preserving the heat for 4-10 hours after the molten iron pouring is finished, opening the upper die after the heat preservation is finished, cooling and solidifying for 3-5 minutes, and forming a track plate original piece with a fixed shape after the molten iron;

a pouring post-treatment process, namely removing large blocks of residual gravels on the surface of the original crawler plate, then placing the original crawler plate into a shot blasting machine for rough shot blasting, wherein shot used in the rough shot blasting is 2-3 mm in diameter, shot blasting time is 8-12 minutes, and then cutting and removing runners, risers and surface burrs generated in the pouring process in a thermal cutting mode;

a heat treatment pretreatment process, wherein the surface of the original creeper tread is subjected to rough grinding and fine grinding, redundant burrs on the surface of the original creeper tread are further removed, the surface defect of the original creeper tread is inspected after the fine grinding is finished, the surface of the original creeper tread is required to be repaired when the defect does not meet the inspection requirement, the original creeper tread is required to be repaired, the original creeper tread cannot be repaired, and the original creeper tread is required to be marked as a waste part;

a heat treatment process, namely sequentially carrying out a normalizing process, a quenching and tempering process and a surface quenching process on the original crawler plate, carrying out strength inspection after the treatment is finished, and obtaining a semi-finished crawler plate after the strength inspection is passed;

a heat treatment post-treatment process, wherein a dead head on the surface of a semi-finished product of the crawler plate is subjected to finish milling, and then finish shot blasting is performed, wherein the diameter of a shot used in the finish shot blasting is 1.2-1.5 mm, and the shot blasting time is 14-18 minutes; and the number of the first and second groups,

and a final treatment process, namely inspecting the surface defects and the internal defects of the semi-finished product of the track plate, coating after the inspection is finished, and then warehousing and storing.

By adopting the technical scheme, in the whole manufacturing process, the surface quality of the track shoe is inspected for many times, such as a heat treatment pretreatment process and a final treatment process, so that possible surface defects of the track shoe are effectively reduced, and the strength of the track shoe is further improved. In the heat treatment process, the original parts of the track shoe are subjected to normalizing treatment and modulating treatment in sequence, so that the strength of the original parts of the track shoe is greatly improved, and meanwhile, the strength and the wear resistance of the surface of the track shoe are further improved through the surface quenching treatment process.

In a preferred example, the invention may be further configured that, in the heat treatment process, the target temperature of the normalizing process is 880-920 ℃, the time of the normalizing process is 9-13 hours, and after the normalizing process is finished, the track shoe original is cooled to 300 ℃ and then subjected to the quenching and tempering process.

In a preferred example, the present invention may be further configured such that in the normalizing process, the equipment used is a high temperature heat treatment furnace, the first 6-8 hours are heating processes, and the temperature in the high temperature heat treatment furnace is uniformly increased to the target temperature of the normalizing process during the heating processes;

the last 3-5 hours is a heat preservation process, the temperature in the high-temperature heat treatment furnace is kept stable in the period, and the difference between the highest temperature and the lowest temperature in the period is not more than 20 ℃.

Through adopting above-mentioned technical scheme, can effectively refine the as-cast structure of grip-pad original paper, the residual stress that exists after the casting inside the grip-pad original paper of preliminary elimination.

In a preferred example of the present invention, the conditioning treatment may include a heating treatment step, a whole quenching treatment step, and a high-temperature tempering treatment step, which are performed in this order, wherein a target temperature of the heating treatment step is the same as a target temperature of the normalizing treatment step, a temperature rise process of the heating treatment step is the same as a temperature rise process of the normalizing treatment step, and a heat retention process of the heating treatment step is shortened by 1 hour compared to a heat retention process of the normalizing treatment step.

By adopting the technical scheme, the heating treatment process is equivalent to carrying out secondary normalizing on the original parts of the track shoe, and further refining the as-cast structure.

In a preferred example, the invention may be further configured that, in the overall quenching treatment process, the adopted quenching liquid is industrial saline with a mass concentration of 8% -10%, and the track shoe original after the heating treatment process needs to be transferred within 30-40 seconds and immersed into the quenching liquid to complete quenching.

By adopting the technical scheme, the hardenability of the original parts of the track shoe in the quenching process can be effectively improved by the industrial saline water with the mass concentration of 8% -10%.

In a preferred example, the target temperature of the high-temperature tempering treatment process is 550-650 ℃, the original crawler plate is uniformly heated for 3-4 hours to reach the target temperature of the high-temperature tempering treatment process, then the temperature is maintained for 3-5 hours, and the original crawler plate is cooled by adopting a water cooling mode after the temperature is maintained, wherein the target temperature of the temperature is 100-150 ℃.

In a preferred example, the surface quenching treatment process may be performed by a special surface quenching device, the surface quenching device heats the specified area of the surface of the track shoe original in an induction heating manner, the target temperature of the surface quenching treatment process is 900-.

In a preferred example, the invention may be further configured to perform a low temperature tempering treatment on the track shoe original after the surface quenching treatment process is completed, wherein a target temperature of the low temperature tempering treatment is 180-.

In conclusion, the invention has the following beneficial effects:

1. the surface quenching treatment process can improve the strength of the appointed area of the surface of the track shoe and the wear resistance of the surface of the track shoe;

2. by using industrial brine as the quenching liquid in the integral quenching treatment process, the hardenability of the quenching liquid to the track shoe original can be effectively improved, so that the track shoe original can generate more martensite in the quenching process.

Detailed Description

The invention discloses a manufacturing process of a crawler plate of a crawler crane, which comprises the following steps:

and a mold manufacturing process of forming an upper mold and a lower mold using the sand and the mold shell, manufacturing an inner core using furan resin sand, then installing the inner core into the lower mold correspondingly, and closing the upper mold and the lower mold.

A raw material smelting step of smelting the recovered scrap iron raw material in an environment of 1530-1550 ℃ to obtain molten iron.

Pouring, namely pouring the molten iron obtained in the raw material smelting step into a pouring hole of an upper die, heating the molten iron to 1620-1640 ℃ before pouring, preserving the heat for 4-10 hours after the molten iron is poured, opening the upper die after the heat preservation is finished, controlling the temperature of a casting to be 600-700 ℃ when the upper die is opened, and then cooling and solidifying for 3-5 minutes until the molten iron forms a track plate original piece with a fixed shape.

And a post-treatment process of pouring, namely removing large blocks of residual gravels on the surface of the original crawler plate, then placing the original crawler plate into a shot blasting machine for rough shot blasting, wherein shot used in the rough shot blasting is 2-3 mm in diameter, shot blasting time is 8-12 minutes, and then cutting and removing runners, risers and surface burrs generated in the pouring process in a thermal cutting mode.

The method comprises a heat treatment pretreatment process, wherein rough grinding and fine grinding are carried out on the surface of the original crawler plate, redundant burrs on the surface of the original crawler plate are further removed, the surface defect of the original crawler plate is inspected after the fine grinding is finished, the inspection requirement is not met, the surface of the original crawler plate needs to be repaired, the original crawler plate cannot be repaired, and the original crawler plate needs to be marked as a waste part.

And in the normalizing treatment process, the target temperature of the normalizing treatment process is 880-920 ℃, the original parts of the track shoe reach the target temperature of the normalizing treatment process through a uniform temperature rise process for 6-8 hours, and then the track shoe is subjected to heat preservation for 3-5 hours, wherein the difference between the highest temperature and the lowest temperature in the heat preservation period of the normalizing treatment process is not more than 20 ℃.

And a heating treatment process, namely after the normalizing treatment process is finished, carrying out a heating treatment process after the original parts of the track shoe are cooled to 300 ℃, wherein the target temperature of the heating treatment process is the same as that of the normalizing treatment process, the heating process of the heating treatment process is the same as that of the normalizing treatment process, and the heat preservation process of the heating treatment process is shortened by 1 hour compared with that of the normalizing treatment process.

And in the whole quenching treatment process, the adopted quenching liquid is industrial salt water with the mass concentration of 8-10%, and the original parts of the track plate after the heating treatment process need to be transferred within 30-40 seconds and immersed into the quenching liquid to finish quenching.

The high-temperature tempering treatment process comprises the steps of 550-650 ℃ as a target temperature, uniformly heating the original crawler plate for 3-4 hours to reach the target temperature of the high-temperature tempering treatment process, then preserving heat for 3-5 hours, and cooling the original crawler plate by adopting a water cooling mode after finishing heat preservation, wherein the target temperature of temperature reduction is 100-150 ℃.

The surface quenching treatment process comprises a surface quenching treatment process, wherein the surface quenching treatment process is carried out by special surface quenching equipment, the surface quenching equipment heats a specified area of the surface of the original crawler plate in an induction heating mode, the target temperature of the surface quenching treatment process is 900-.

And a low-temperature tempering treatment step, wherein after the surface quenching treatment step, the target temperature of the low-temperature tempering treatment is 220 ℃, the time of the low-temperature tempering treatment is 4-5 hours, after the low-temperature tempering, the original part of the track plate is subjected to strength inspection, and after the strength inspection is passed, a semi-finished product of the track plate can be obtained.

And in the heat treatment post-treatment process, a dead head on the surface of the semi-finished product of the crawler plate is subjected to finish milling, and then finish shot blasting is performed, wherein the diameter of a shot used in the finish shot blasting is 1.2-1.5 mm, and the shot blasting time is 14-18 minutes.

And a final treatment process, namely inspecting the surface defects and the internal defects of the semi-finished product of the track plate, coating after the inspection is finished, and then warehousing and storing.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.