Cabin raft frame heat treatment anti-deformation tool and method
By designing a raft frame heat treatment tooling with adjustable connecting seats and prestressed tensile parts, the problem that the existing tooling cannot adapt to a variety of raft frames structures is solved, deformation control and improved tissue uniformity during the heat treatment process are achieved, and production costs and cycles are reduced.
Patent Information
- Application Number
- CN202511163445.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-19
- Publication Date
- 2025-10-10
AI Technical Summary
Existing metal structure heat treatment tooling cannot adapt to a variety of raft structures, resulting in deformation exceeding the tolerance during the heat treatment process. In addition, there is a lack of real-time compensation mechanism, and it is impossible to effectively control the deformation caused by thermal expansion and cooling contraction.
A heat treatment anti-deformation tooling for raft frames was designed, which included an adjustable connecting seat and prestressed tensile parts. The position and height could be flexibly adjusted through bolt holes and positioning bolts. Heat-resistant alloy pull rods and hydraulic cylinders were used to apply prestress during the heat treatment process to offset the deformation caused by thermal expansion and cooling contraction.
It achieves flexible adaptability of tooling, reduces production costs and cycles, effectively controls deformation during heat treatment, improves organizational uniformity and eliminates residual stress, and ensures the dimensional accuracy and life of the product.
Smart Images
Figure CN120758722A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of heat treatment of metal structures, and in particular to a heat treatment anti-deformation tool and method for a raft frame. Background Art
[0002] In the field of metal structure heat treatment technology, raft scaffolding, as a key ship shock-absorbing component, is usually manufactured using large welded steel structures. This type of raft scaffolding has a complex structure, including multiple protruding supports and cantilever structures. It needs to withstand high-frequency vibration and impact loads during service, so there are strict requirements on the mechanical properties of the material (such as strength, toughness and fatigue life). Heat treatment processes (such as annealing or normalizing) are key links to improve the uniformity of the internal structure of the raft scaffolding and eliminate welding residual stress. However, in the traditional heat treatment process, the raft scaffolding is easily affected by uneven heating and cooling gradients, and uncontrollable deformation such as shrinkage, bending or warping occurs. This will lead to dimensional deviations, reduced assembly accuracy, and even stress concentration, which will reduce product life.
[0003] In the prior art, anti-deformation tooling usually adopts a fixed support structure, such as an integral welded frame or a simple bolt-connected base. These solutions have several significant drawbacks: First, the size of the raft and the position of the protruding supports vary with different ship types, but existing tooling is mostly one-to-one custom design, which cannot flexibly adjust the height or position of the support points. When the raft structure changes, the tooling needs to be remade, increasing costs and time. Second, during the heat treatment heating stage, the thermal expansion coefficient of the metal is high (for example, the α value of carbon steel is about 13.5×10 -6 / °C), but existing tooling lacks a real-time compensation mechanism. For example, during the 300-620°C heating process, the raft frame is prone to lateral bending due to uneven thermal expansion along its length, while the cantilever supports along its width are prone to contraction and deformation during cooling. Existing technology relies solely on rigid constraints and is unable to apply prestress to offset deformation, resulting in the finished product deformation often exceeding the ±2mm tolerance standard. In view of this, the present invention proposes a heat treatment anti-deformation tool and method for a raft frame. Summary of the Invention
[0004] The present invention provides a raft frame heat treatment anti-deformation tool and method, which solves the problem that the existing technology cannot adapt to various forms of raft frame structures.
[0005] The technical solution of the present invention is as follows: A raft frame heat treatment anti-deformation tool, including a tool frame, the top surface of the tool frame is provided with a plurality of bolt holes distributed in an array, the top of the tool frame is provided with a plurality of connecting seats for placing the raft frame, the connecting seat includes a first base plate, the four corners of the first base plate are provided with first fastening bolts, the first fastening bolts pass through the first base plate and are threadedly engaged with the corresponding bolt holes, the top of the first base plate is fixedly connected to a fixed round tube, the top of the fixed round tube is inserted with a movable round tube, the outside of the fixed round tube is provided with a plurality of positioning bolts distributed in a ring, and the plurality of positioning bolts pass through the side wall of the fixed round tube and are threadedly connected to the movable round tube.
[0006] Preferably, a plurality of positioning holes that are threadably matched with the positioning bolts are opened on the outer side of the movable circular tube, and the plurality of positioning holes are equidistantly distributed along the axial direction of the movable circular tube.
[0007] Preferably, both ends of the movable circular tube are fixedly connected to limit bars, and the inner wall of the limit bar is provided with a limit groove which is gap-matched with the limit bar.
[0008] Preferably, a plurality of annularly distributed stiffening plates are fixedly connected to the outer side of the fixed circular tube, the number of the stiffening plates is the same as the number of the positioning bolts, and the plurality of the positioning bolts are located between two adjacent stiffening plates.
[0009] Preferably, the four corners of the tooling frame are provided with lifting ears, and the four lifting ears are welded to the top wall of the tooling frame.
[0010] Preferably, both ends of the top of the tooling frame along the length direction of the raft are provided with transverse stretching pieces, and both ends of the top of the tooling frame along the width direction of the raft are provided with longitudinal stretching pieces.
[0011] Preferably, the transverse stretching member includes a second base plate, and second fastening bolts are provided at the four corners of the second base plate. The second fastening bolts pass through the second base plate and are threadedly engaged with corresponding bolt holes. The top of the second base plate is fixedly connected to a first ear seat, and a heat-resistant alloy pull rod is hinged on the inner side of the first ear seat. The end of the heat-resistant alloy pull rod away from the first ear seat is connected to the raft support.
[0012] Preferably, the longitudinal stretching member includes a third base plate, and the four corners of the third base plate are each provided with a third fastening bolt, and the third fastening bolt passes through the third base plate and is threadedly engaged with the corresponding bolt hole. The top of the third base plate is fixedly connected to a second ear seat, and the inner side of the second ear seat is hinged with a heat-resistant hydraulic cylinder, and the output end of the heat-resistant hydraulic cylinder is connected to the bottom surface of the raft support.
[0013] The present invention also provides a method for preventing deformation of a raft frame by heat treatment, which is implemented according to a tool for preventing deformation of a raft frame by heat treatment, and includes the following steps: Step 1: First, install a corresponding number of connecting seats on the top of the tooling frame according to the number and position of the protruding supports of the raft frame. The specific implementation process is as follows: A1. Adjust the movable circular tube to the position directly below the protruding support of the raft frame, and then thread the first fastening bolt into the corresponding bolt hole to fix the first base plate to the tooling frame; A2. Adjust the height of the movable round tube to match the height of the protruding support of the raft frame, then turn the positioning bolt to match the thread of the movable round tube to fix the movable round tube to the fixed round tube; Step 2: Hoist the tooling frame to the heat treatment furnace platform, place the raft on the connecting seat, and spot weld the protruding support of the raft to the movable round tube; Step 3: Install transverse and longitudinal stretching parts. The specific implementation process is as follows: B1. Connect the top ends of the two heat-resistant alloy tie rods to the raft supports at both ends of the raft in the longitudinal direction, and then fix the second bottom plate to the tooling frame through the second fastening bolts; B2. Connect the top beams of the two heat-resistant hydraulic cylinders to the bottom of the raft cantilever supports at both ends of the raft in the width direction, and then fix the third bottom plate to the tooling frame through the third fastening bolts; Step 4: heat-treat the raft frame, and then disassemble the connecting seat, transverse stretching parts and longitudinal stretching parts for recycling and reuse.
[0014] Preferably, in step 4, the specific process of heat treatment of the raft is as follows: C1. Temperature rise in stages in the furnace: The temperature of the first stage is 25-300℃, the heating rate is 80℃ / h, the duration is 3.5 hours, the temperature and strain are recorded every 30 minutes, and the heating is suspended when the temperature difference of the same section is greater than 30℃, and restarted after equilibrium; The second stage temperature is 300-450℃, the heating rate is 60℃ / h, the duration is 2.5 hours, and the thermal expansion (ΔL=α·L·ΔT, α=13.5×10 -6 / ℃, L=characteristic length), the hydraulic system opens the temperature compensation valve; The third stage temperature is 450-620℃, the heating rate is 40℃ / h, and the duration is 4.25 hours. At 450℃, check the connection seat bolts and tighten them again. After exceeding 600℃, the automatic pressure replenishment function of the hydraulic cylinder is turned off. C2. Keep the temperature in the furnace at 620±10℃ for 4 hours; C3. Start the cooling equipment for gradient cooling: In the first stage, the furnace top air cooling system is turned on, the cooling temperature is from 620-550℃, the cooling rate is 50℃ / h, and the duration is 1.4 hours; In the second stage, the side wall air cooling nozzle is started, the cooling temperature is from 550-450℃, the cooling rate is 40℃ / h, and the duration is 2.5 hours; The third stage cooling temperature is from 450-300℃, the cooling rate is 30℃ / h, and the duration is 5 hours; C4. After maintaining constant temperature at 300℃ for 1h, release all prestress and prepare for tooling dismantling.
[0015] The working principle and beneficial effects of the present invention are: 1. The connecting seat cooperates with the bolt hole of the tooling frame through the first fastening bolt to achieve fine-tuning of the position. The movable round tube cooperates with the thread of the positioning hole through the positioning bolt to adjust the height equidistantly along the axial direction to ensure that it matches the height of the protruding support of the raft frame. This solves the problem that the existing fixed tooling cannot cope with the diversity of the raft frame. The user can freely adjust according to the number and position of the protruding supports of the raft frame without having to customize the tooling again, reducing production costs and cycles.
[0016] 2. By installing heat-resistant alloy tie rods and heat-resistant hydraulic cylinders in the directions (transverse and longitudinal) where the raft supports are prone to shrinkage or bending, the heat-resistant alloy tie rods can apply prestressed tension to the supports in the length direction of the raft, and the heat-resistant hydraulic cylinders can apply prestressed pressure to the supports in the width direction of the raft, so that the raft produces a slight reverse deformation. During the heat treatment process, thermal expansion will partially offset this prestress. When cooling and shrinking, the prestress will help resist shrinkage deformation, thereby effectively avoiding the problem of raft deformation during the heat treatment process.
[0017] 3. Combining tooling with segmented heat treatment process, precise control of temperature gradient is achieved, thermal deformation is reduced from the source, the uniformity of the structure is improved during the holding stage (620±10℃), and residual stress is eliminated to prevent deformation. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0019] Figure 1 This is a schematic diagram of the structure of a heat treatment anti-deformation tool for a raft frame of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of a heat treatment anti-deformation tool for a raft frame of the present invention. Figure 2 ; Figure 3 The structure of the connecting seat of the present invention is shown as follows Figure 1 ; Figure 4 The structure of the connecting seat of the present invention is shown as follows Figure 2 ; Figure 5 for Figure 4A schematic diagram of the enlarged structure of part A; Figure 6 It is a schematic structural diagram of the transverse stretching member of the present invention; Figure 7 It is a schematic structural diagram of the transverse stretching member of the present invention.
[0020] In the figure: 1. tooling frame; 2. bolt hole; 3. connecting seat; 31. first base plate; 32. first fastening bolt; 33. fixed round tube; 34. movable round tube; 35. positioning bolt; 36. positioning hole; 37. stiffening plate; 38. limit strip; 39. limit groove; 4. transverse stretching member; 41. second base plate; 42. second fastening bolt; 43. first ear seat; 44. heat-resistant alloy pull rod; 5. lifting ear; 6. longitudinal stretching member; 61. third base plate; 62. third fastening bolt; 63. second ear seat; 64. heat-resistant hydraulic cylinder. DETAILED DESCRIPTION
[0021] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.
[0022] Example 1: like Figures 1 to 7 As shown, this embodiment proposes a heat treatment anti-deformation tool for a raft frame, comprising a tool frame 1, four corners of the tool frame 1 are provided with lifting ears 5, the four lifting ears 5 are welded to the top wall of the tool frame 1, the top surface of the tool frame 1 is provided with a plurality of bolt holes 2 distributed in an array, the top of the tool frame 1 is provided with a plurality of connection seats 3 for placing the raft frame, the connection seat 3 includes a first bottom plate 31, the four corners of the first bottom plate 31 are provided with first fastening bolts 32, the first fastening bolts 32 pass through the first bottom plate 31 and the corresponding The corresponding bolt holes 2 are threadedly matched, and a fixed circular tube 33 is fixedly connected to the top of the first base plate 31. A movable circular tube 34 is inserted into the top of the fixed circular tube 33. A number of positioning bolts 35 distributed in a ring are provided on the outside of the fixed circular tube 33. The positioning bolts 35 all penetrate the side wall of the fixed circular tube 33 and are threadedly connected to the movable circular tube 34. A number of positioning holes 36 that are threadedly matched with the positioning bolts 35 are opened on the outside of the movable circular tube 34. The positioning holes 36 are equidistantly distributed along the axial direction of the movable circular tube 34.
[0023] The connection base 3 is installed by threaded engagement with the bolt hole 2 of the tooling frame 1 through the first fastening bolt 32. The design adopts a detachable structure that allows the position of the connection base 3 to be flexibly adjusted, so that the installation position can be adjusted according to the position of the protruding support of the raft frame, and is applicable to various raft frame structures. By loosening the positioning bolts 35, the movable circular tube 34 can be moved vertically, so that the height of the movable circular tube 34 can be adjusted. The movable circular tube 34 is then locked by tightening the positioning bolts 35 to determine the height. This design can adjust the height of the protruding support according to the raft structure, is applicable to a variety of raft structures, and greatly improves the flexibility of the tooling.
[0024] Furthermore, both ends of the movable circular tube 34 are fixedly connected to the limit bars 38 , and the inner wall of the limit bars 38 is provided with a limit groove 39 that is clearance-matched with the limit bars 38 .
[0025] The limit bar 38 can limit the relative rotation between the movable circular tube 34 and the fixed circular tube 33, thereby preventing the position of the positioning hole 36 and the positioning bolt 35 from being offset, thereby ensuring that the positioning bolt 35 can be accurately aligned with the positioning hole 36 after the height of the movable circular tube 34 is adjusted, thereby improving the stability of the overall structure.
[0026] Furthermore, a plurality of annularly distributed stiffening plates 37 are fixedly connected to the outer side of the fixed circular tube 33 . The number of stiffening plates 37 is the same as the number of positioning bolts 35 , and a plurality of positioning bolts 35 are located between two adjacent stiffening plates 37 .
[0027] The design of the stiffening plate 37 can improve the compressive strength of the fixed circular tube 33, thereby strengthening the support of the fixed circular tube 33 for raft structures of multiple sizes, and effectively avoiding the problem of deformation of the fixed circular tube 33 due to insufficient compressive resistance.
[0028] Furthermore, the top of the tooling frame 1 is provided with transverse stretching members 4 at both ends along the length direction of the raft frame, and the top of the tooling frame 1 is provided with longitudinal stretching members 6 at both ends along the width direction of the raft frame; the transverse stretching member 4 includes a second bottom plate 41, and the four corners of the second bottom plate 41 are provided with second fastening bolts 42, the second fastening bolts 42 pass through the second bottom plate 41 and are threadedly engaged with the corresponding bolt holes 2, the top of the second bottom plate 41 is fixedly connected with a first ear seat 43, and the inner side of the first ear seat 43 is hinged with a durable The hot alloy pull rod 44, the end of the heat-resistant alloy pull rod 44 away from the first ear seat 43 is connected to the raft support; the longitudinal tensile member 6 includes a third base plate 61, and the four corners of the third base plate 61 are provided with third fastening bolts 62. The third fastening bolts 62 pass through the third base plate 61 and are threadedly engaged with the corresponding bolt holes 2. The top of the third base plate 61 is fixedly connected to the second ear seat 63, and the inner side of the second ear seat 63 is hinged with a heat-resistant hydraulic cylinder 64. The output end of the heat-resistant hydraulic cylinder 64 is connected to the bottom surface of the raft support.
[0029] By installing heat-resistant alloy pull rods 44 and heat-resistant hydraulic cylinders 64 in the directions (transverse and longitudinal) where the raft supports are prone to shrinkage or bending, the heat-resistant alloy pull rods 44 can apply prestressed tension to the supports in the length direction of the raft, and the heat-resistant hydraulic cylinders 64 can apply prestressed pressure to the supports in the width direction of the raft, so that the raft produces a slight reverse deformation. During the heat treatment process, thermal expansion will partially offset this prestress. During cooling and shrinkage, the prestress helps to resist shrinkage deformation, thereby effectively avoiding the problem of deformation of the raft during the heat treatment process.
[0030] Example 2: This embodiment proposes a method for preventing deformation of a raft frame by heat treatment, which is implemented according to the raft frame heat treatment anti-deformation tooling in the first embodiment, including the following steps: Step 1: First, install a corresponding number of connecting seats 3 on the top of the tooling frame 1 according to the number and position of the protruding supports of the raft frame. The specific implementation process is as follows: A1. Adjust the movable circular tube 34 to the position directly below the protruding support of the raft frame, and then thread the first fastening bolts 32 into the corresponding bolt holes 2 to secure the first base plate 31 to the tooling frame 1. A2. Adjust the height of the movable circular tube 34 so that it matches the height of the protruding support of the raft frame, then rotate the positioning bolt 35 to engage with the thread of the movable circular tube 34 to fix the movable circular tube 34 to the fixed circular tube 33; Step 2: hoist the tooling frame 1 to the heat treatment furnace platform, place the raft on the connecting seat 3, and spot weld the protruding support of the raft to the movable circular tube 34; Step 3: Install the transverse stretching member 4 and the longitudinal stretching member 6. The specific implementation process is as follows: B1. Connect the top ends of the two heat-resistant alloy tie rods 44 to the raft supports at both ends of the raft in the longitudinal direction, and then fix the second bottom plate 41 to the tooling frame 1 using the second fastening bolts 42; B2. Connect the top beams of the two heat-resistant hydraulic cylinders 64 to the bottom of the raft cantilever supports at both ends of the raft in the width direction, and then fix the third bottom plate 61 to the tooling frame 1 through the third fastening bolts 62; Step 4: heat-treating the raft frame, and then disassembling the connecting seat 3, the transverse stretching member 4 and the longitudinal stretching member 6 for recycling and reuse.
[0031] Furthermore, in step 4, the specific process of heat treatment of the raft is as follows: C1. Temperature rise in stages in the furnace: The temperature of the first stage is 25-300℃, the heating rate is 80℃ / h, the duration is 3.5 hours, the temperature and strain are recorded every 30 minutes, and the heating is suspended when the temperature difference of the same section is greater than 30℃, and restarted after equilibrium; The second stage temperature is 300-450℃, the heating rate is 60℃ / h, the duration is 2.5 hours, and the thermal expansion (ΔL=α·L·ΔT, α=13.5×10 -6 / ℃, L=characteristic length), the hydraulic system opens the temperature compensation valve; The third stage temperature is 450-620℃, the heating rate is 40℃ / h, and the duration is 4.25 hours. At 450℃, check the connection seat bolts and tighten them again. After exceeding 600℃, the automatic pressure replenishment function of the hydraulic cylinder is turned off. C2. Keep the temperature in the furnace at 620±10℃ for 4 hours; C3. Start the cooling equipment for gradient cooling: In the first stage, the furnace top air cooling system is turned on, the cooling temperature is from 620-550℃, the cooling rate is 50℃ / h, and the duration is 1.4 hours; In the second stage, the side wall air cooling nozzle is started, the cooling temperature is from 550-450℃, the cooling rate is 40℃ / h, and the duration is 2.5 hours; The third stage cooling temperature is from 450-300℃, the cooling rate is 30℃ / h, and the duration is 5 hours; C4. After maintaining constant temperature at 300℃ for 1h, release all prestress and prepare for tooling dismantling.
[0032] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A heat treatment anti-deformation tool for a raft frame, comprising a tool frame (1), characterized in that: The top surface of the tooling frame (1) is provided with a plurality of bolt holes (2) distributed in an array, and the top of the tooling frame (1) is provided with a plurality of connection seats (3) for placing the raft frame, and the connection seat (3) includes a first bottom plate (31), and the four corners of the first bottom plate (31) are provided with first fastening bolts (32), and the first fastening bolts (32) pass through the first bottom plate (31) and are threadedly engaged with the corresponding bolt holes (2), and the top of the first bottom plate (31) is fixedly connected with a fixed circular tube (33), and the top end of the fixed circular tube (33) is plugged with a movable circular tube (34), and the outer side of the fixed circular tube (33) is provided with a plurality of positioning bolts (35) distributed in an annular shape, and the plurality of positioning bolts (35) pass through the side wall of the fixed circular tube (33) and are threadedly connected to the movable circular tube (34).
2. The heat treatment anti-deformation tool for raft frame according to claim 1, characterized in that: A plurality of positioning holes (36) threadedly engaged with the positioning bolts (35) are provided on the outer side of the movable circular tube (34), and the plurality of positioning holes (36) are equidistantly distributed along the axial direction of the movable circular tube (34).
3. The anti-deformation tool for heat treatment of a raft frame according to claim 2, characterized in that: Both ends of the movable circular tube (34) are fixedly connected to the limiting strip (38), and the inner wall of the limiting strip (38) is provided with a limiting groove (39) that is clearance-matched with the limiting strip (38).
4. The heat treatment anti-deformation tool for a raft frame according to claim 1, characterized in that: A plurality of annularly distributed stiffening plates (37) are fixedly connected to the outer side of the fixed circular tube (33). The number of the stiffening plates (37) is the same as the number of the positioning bolts (35). The plurality of positioning bolts (35) are located between two adjacent stiffening plates (37).
5. The anti-deformation tool for heat treatment of raft frame according to claim 1, characterized in that: Lifting ears (5) are provided at the four corners of the tooling frame (1), and the four lifting ears (5) are welded to the top wall of the tooling frame (1).
6. The heat treatment anti-deformation tool for raft frame according to claim 1, characterized in that: Both ends of the top of the tooling frame (1) along the length direction of the raft frame are provided with transverse stretching members (4), and both ends of the top of the tooling frame (1) along the width direction of the raft frame are provided with longitudinal stretching members (6).
7. The anti-deformation tool for heat treatment of a raft frame according to claim 6, characterized in that: The transverse stretching member (4) includes a second base plate (41), and second fastening bolts (42) are provided at the four corners of the second base plate (41). The second fastening bolts (42) pass through the second base plate (41) and are threadedly engaged with the corresponding bolt holes (2). The top of the second base plate (41) is fixedly connected to a first ear seat (43), and the inner side of the first ear seat (43) is hinged with a heat-resistant alloy pull rod (44), and the end of the heat-resistant alloy pull rod (44) away from the first ear seat (43) is connected to the raft support.
8. The heat treatment anti-deformation tool for raft frame according to claim 7, characterized in that: The longitudinal stretching member (6) includes a third bottom plate (61), and third fastening bolts (62) are provided at four corners of the third bottom plate (61). The third fastening bolts (62) pass through the third bottom plate (61) and are threadedly engaged with corresponding bolt holes (2). The top of the third bottom plate (61) is fixedly connected to a second ear seat (63), and the inner side of the second ear seat (63) is hinged with a heat-resistant hydraulic cylinder (64), and the output end of the heat-resistant hydraulic cylinder (64) is connected to the bottom surface of the raft support.
9. A method for preventing deformation of a raft frame by heat treatment, which is implemented by the raft frame heat treatment anti-deformation tool according to claim 8, characterized in that: The steps include: Step 1: First, according to the number and position of the protruding supports of the raft frame, a corresponding number of connecting seats (3) are installed on the top of the tooling frame (1). The specific implementation process is as follows: A1. Adjust the movable circular tube (34) to the position directly below the protruding support of the raft frame, and then thread the first fastening bolt (32) into the corresponding bolt hole (2) to fix the first bottom plate (31) to the tooling frame (1); A2. Adjust the height of the movable circular tube (34) to match the height of the protruding support of the raft frame, then rotate the positioning bolt (35) to engage the thread of the movable circular tube (34) to fix the movable circular tube (34) to the fixed circular tube (33); Step 2: hoist the tooling frame (1) to the heat treatment furnace platform, place the raft frame on the connecting seat (3), and spot weld the protruding support of the raft frame to the movable circular tube (34); Step 3: Install the transverse stretching member (4) and the longitudinal stretching member (6). The specific implementation process is as follows: B1. Connect the top ends of the two heat-resistant alloy tie rods (44) to the raft supports at both ends of the raft in the longitudinal direction, and then fix the second bottom plate (41) to the tooling frame (1) through the second fastening bolts (42); B2. Connect the top beams of the two heat-resistant hydraulic cylinders (64) to the bottom of the raft cantilever supports at both ends of the raft in the width direction, and then fix the third bottom plate (61) to the tooling frame (1) through the third fastening bolts (62); Step 4: heat-treating the raft frame, and then disassembling the connecting seat (3), the transverse stretching member (4) and the longitudinal stretching member (6) for recycling and reuse.
10. A method for preventing deformation of a raft frame by heat treatment according to claim 9, characterized in that: In step 4, the specific process of heat treatment of the raft is as follows: C1. Staged heating in the furnace: The temperature of the first stage is 25-300℃, the heating rate is 80℃ / h, the duration is 3.5 hours, the temperature and strain are recorded every 30 minutes, and the heating is suspended when the temperature difference of the same section is greater than 30℃, and restarted after equilibrium; The second stage temperature is 300-450℃, the heating rate is 60℃ / h, the duration is 2.5 hours, and the thermal expansion (ΔL=α·L·ΔT, α=13.5×10 -6 / ℃, L=characteristic length), the hydraulic system opens the temperature compensation valve; The temperature of the third stage is 450-620℃, the heating rate is 40℃ / h, and the duration is 4.25 hours. At 450℃, check the connection seat bolts and tighten them again. After exceeding 600℃, turn off the automatic pressure replenishment function of the hydraulic cylinder; C2. Keep the temperature in the furnace at 620±10℃ for 4 hours; C3. Start the cooling equipment for gradient cooling: In the first stage, the furnace top air cooling system is turned on, the cooling temperature is from 620-550℃, the cooling rate is 50℃ / h, and the duration is 1.4 hours; In the second stage, the side wall air cooling nozzle is started, the cooling temperature is from 550-450℃, the cooling rate is 40℃ / h, and the duration is 2.5 hours; The third stage cooling temperature is from 450-300℃, the cooling rate is 30℃ / h, and the duration is 5 hours; C4. After maintaining constant temperature at 300℃ for 1h, release all prestress and prepare for tooling removal.