Large crankshaft heating process test tool assembly

Abstract

The utility model discloses a large crankshaft heating process test tool assembly which comprises a heating furnace and a test crankshaft. The upper furnace wall and the lower furnace wall of the heating furnace are each provided with at least three hearth temperature thermocouples, the upper surfaces of step shafts on the two sides of a crank pin of the test crankshaft are each provided with a core deep hole used for arranging the core temperature thermocouples, and the inner side of each core deep hole is evenly provided with at least two shallow holes at intervals. Four shallow holes are machined in the surface of the outer circle of a main journal in a heating furnace, a shallow hole is machined in the surface of the axial symmetry face of a step on the two sides of a crank pin of a tested crankshaft, and a surface temperature thermocouple is arranged in each shallow hole. A mode of combining in-furnace and furnace mouth multi-point temperature measurement and crankshaft step axis part and surface temperature measurement is adopted, the uniformity in a 270 crankshaft heating furnace is detected, whether the heating temperature of each part of a crankshaft step shaft meets the crankshaft forging temperature requirement or not is detected, the arrangement structure is simple, and operation is convenient.

Description

Technical Field

[0001] The utility model belongs to the technical field of crankshaft forging heating, and in particular relates to a large crankshaft heating process testing tool assembly. Background Art

[0002] In terms of temperature uniformity of crankshaft heating, the surface temperature measurement of the crankshaft can meet the process requirement of 1250℃, but the core temperature deviation is large (1135~1151℃). During TR upsetting, the crankshaft balance block surface is prone to meat shortage, which does not meet the processing requirements; at the same time, the heating time is as long as five hours, the crankshaft has a high degree of oxidation and a thick oxide scale, which affects the crankshaft forming quality.

[0003] Chinese invention patent application (202410312366.6) discloses a method for heating a compressor crankshaft and a compressor crankshaft heating device thereof. The method includes setting a PTC heating belt; collecting current when the PTC heating belt is powered on for heating; obtaining the temperature of the PTC heating belt, the temperature difference between the PTC heating belt and the lubricating oil, and calculating the lubricating oil temperature based on the current; comparing the lubricating oil temperature with a preset lubricating oil pour point; if the lubricating oil temperature is greater than the preset lubricating oil pour point, preheating is stopped; if the lubricating oil temperature is less than the preset lubricating oil pour point, preheating is continued until the lubricating oil temperature is greater than the preset lubricating oil pour point. The invention only records the crankshaft heating process, but it is impossible to know whether the crankshaft is heated evenly. Summary of the Invention

[0004] The purpose of this utility model is to solve the above technical problems and provide a large crankshaft heating process test tooling assembly, which can test the uniformity of the 270 crankshaft heating furnace and at the same time test the heating temperature of each part of the crankshaft step shaft to see whether it meets the crankshaft forging temperature requirements.

[0005] To achieve the above-mentioned purpose, the utility model provides a large crankshaft heating process test tooling assembly, including a heating furnace and a test crankshaft; at least three furnace temperature measuring thermocouples are arranged on the upper furnace wall and the lower furnace wall of the heating furnace, and a core deep hole is processed on the upper surface of the step shaft on both sides of the crank pin of the test crankshaft for arranging the core temperature measuring thermocouple, and at least two shallow holes are processed at even intervals on the inner side of each core deep hole, four shallow holes are processed on the outer cylindrical surface of the main shaft neck in the heating furnace, and a shallow hole is processed on the surface of the step axis symmetric surface on both sides of the crank pin of the test crankshaft, and each shallow hole is arranged with a surface temperature measuring thermocouple.

[0006] Furthermore, the middle furnace temperature measuring thermocouple of the upper furnace wall is a temperature-controlling thermocouple.

[0007] Furthermore, the core temperature measuring thermocouples are arranged symmetrically.

[0008] Furthermore, at least two shallow holes are evenly spaced inside each of the core deep holes, and one of the shallow holes is close to the crank pin.

[0009] Furthermore, the four shallow holes on the outer circumferential surface of the main shaft journal in the heating furnace are evenly arranged along the circumferential direction.

[0010] Compared with the prior art, the beneficial effects of the present invention are: adopting a combination of temperature measurement at multiple points inside the furnace and at the furnace mouth and temperature measurement at the center and surface of the crankshaft step, while inspecting the uniformity inside the 270 crankshaft heating furnace, it also inspects the heating temperature of various parts of the crankshaft step shaft to see whether they meet the crankshaft forging temperature requirements, with a simple layout structure and easy operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the large crankshaft heating process test fixture assembly of the utility model;

[0012] Figure 2 This is a schematic diagram of the thermocouple arrangement;

[0013] Figure 3 This is a schematic diagram of the furnace mouth thermocouple arrangement. DETAILED DESCRIPTION

[0014] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0015] like Figure 1 The large crankshaft heating process test tooling assembly includes a heating furnace and a test crankshaft. The key points of the utility model are: at least three furnace temperature measuring thermocouples a are arranged on the upper and lower furnace walls of the heating furnace, among which the middle furnace temperature measuring thermocouple on the upper furnace wall (above the furnace as shown in the figure) is a temperature-controlled thermocouple; a core deep hole is machined on the upper surface of the step shaft on both sides of the crank pin of the test crankshaft, for arranging the core temperature measuring thermocouple b, and the core temperature measuring thermocouples b are arranged symmetrically; at least two shallow holes are machined evenly spaced inside each core deep hole, and one of the shallow holes is close to the crank pin; four shallow holes are machined on the outer cylindrical surface of the main shaft neck in the heating furnace (and the four shallow holes are evenly arranged along the circumferential direction), and a shallow hole is machined on the surface of the step axis symmetry surface on both sides of the crank pin of the test crankshaft, and each shallow hole is arranged with a surface temperature measuring thermocouple c.

[0016] like Figure 2Arrange the thermocouples. The second point of the furnace temperature measuring thermocouple is a temperature control thermocouple, and the other five are only temperature measuring thermocouples. The second point is about 300mm away from the workpiece, the first and third points are about 200mm away from the workpiece, and the fourth, fifth, and sixth points are about 30mm away from the workpiece. According to the crankshaft heating process, perform pre-upsetting and upsetting heating twice, and increase the insulation temperature to 1260℃ and 1270℃ for 1 hour each. The 6 temperature measuring thermocouples in the furnace, the 8 thermocouples on the step shaft, and the 8 thermocouples on the outer surface of the main shaft neck are measured and recorded at the same time. After insulation, an infrared thermometer is used to measure the surface temperature of the furnace mouth step shaft (built-in thermocouple). The temperature data is required to be recorded every 15 minutes.

[0017] Adjust the distance between point 2 and the workpiece to approximately 70mm, point 1 to approximately 130mm, point 3 to approximately 200mm, and points 4, 5, and 6 to approximately 30mm. Perform pre-upsetting and upsetting heating according to the crankshaft heating process, maintaining the temperature at 1270°C for 1 hour. Other requirements are the same as above.

[0018] like Figure 3 Thermocouples are arranged as shown. Compared with the previous two temperature measurements, four more thermocouples are added at the furnace entrance and four more thermocouples are added at the furnace exit (serial numbers 10, 11, 9, and 12) to heat and keep warm.

[0019] By combining the temperature measurement at multiple points inside and outside the furnace with the temperature measurement at the center and surface of the crankshaft step, the uniformity of the heating of the crankshaft step can be tested at the same time as the uniformity inside the 270 crankshaft heating furnace, providing a basis for the design of the crankshaft heating process.

[0020] The utility model is only for the full-fiber upsetting forging crankshafts of medium and high alloy steel with large aspect ratio and high hardenability; the crankshaft forgings after temperature measurement by the utility model have high material utilization rate, small forging margin and high degree of continuity of metal fiber streamlines.

Claims

1. A large crankshaft heating process test fixture assembly, comprising a heating furnace and a test crankshaft; characterized in that: At least three furnace temperature measuring thermocouples (a) are arranged on the upper and lower furnace walls of the heating furnace, a core deep hole is machined on the upper surface of the stepped shaft on both sides of the crank pin of the test crankshaft, for arranging the core temperature measuring thermocouple (b), at least two shallow holes are machined at even intervals on the inner side of each core deep hole, four shallow holes are machined on the outer cylindrical surface of the main shaft neck in the heating furnace, and a shallow hole is machined on the surface of the stepped axisymmetric surface on both sides of the crank pin of the test crankshaft, and each shallow hole is arranged with a surface temperature measuring thermocouple (c).

2. The large crankshaft heating process test fixture assembly according to claim 1, characterized in that: The middle furnace temperature measuring thermocouple of the upper furnace wall is a temperature-controlling thermocouple.

3. The large crankshaft heating process test fixture assembly according to claim 1, characterized in that: The core temperature measuring thermocouples (b) are arranged symmetrically.

4. The large crankshaft heating process test fixture assembly according to claim 1, characterized in that: At least two shallow holes are evenly spaced inside each of the core deep holes, and one of the shallow holes is close to the crank pin.

5. The large crankshaft heating process test fixture assembly according to claim 1, characterized in that: The four shallow holes on the outer circumferential surface of the main shaft journal in the heating furnace are evenly arranged along the circumferential direction.

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