Large-scale impact runner body forging composite compaction process

Abstract

The application introduces a large impact runner body forging composite compaction process, according to the runner forging process weight matching steel ingot, the steel ingot is integrally pre-drawing; the blank after pre-drawing is full cross-section upsetting compaction; the upsetting blank is rotated around the center of the cross rotating anvil compaction; the blank is turned over 90°, radial roll forging deformation is carried out; the blank is turned over 90°, the spinning anvil is rotated from the blank circumference to the center direction, and the spinning anvil is rotated from the blank circumference to the center direction; the spinning blank is turned over 90°, and the radial roll forging outer circle is carried out; according to the process requirement, the center groove is forged, and the finished product is finished. The axial and radial deformation is increased for several times, the internal defects are welded, the anisotropy characteristics of the forging are improved, and the comprehensive mechanical properties of the forging are improved; the center groove of the two end faces is forged to realize near net shape forming, the metal streamline integrity and performance consistency are ensured; the whole process reduces the fire times, improves the forging efficiency, and the quality is stable, the impact resistance is strong, and the user requirement index is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of forging process, in particular to a large-scale impact type runner body forging composite compaction process. BACKGROUND

[0002] The impact type hydraulic turbine unit has broad application prospect and market potential, the single machine capacity of the hydraulic turbine unit required by the type of hydropower project is huge, and the weight and size of the runner are greatly increased.

[0003] The large-scale impact type runner body forging is a core component required by the generator unit, under the operating condition, it bears high-strength water impact force, centrifugal force, cyclic alternating load, mud impact corrosion and other complex actions, in order to ensure the safe and stable operation of the unit, the internal quality and mechanical properties of the runner body are extremely strict.

[0004] The traditional compaction scheme generally adopts the process scheme of ingot upsetting and elongation-gas cutting blanking-full section upsetting-first rotation into anvil compaction-rolling outer circle-second rotation into anvil compaction, which well guarantees the internal quality of the large-scale runner forging, and the one-time flaw detection qualified rate is higher, but the overall production efficiency is low and the production cycle is long. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art, provide an impact type runner body forging composite compaction process, improve the production efficiency, guarantee the overall performance consistency of the forging, and improve the comprehensive mechanical properties of the forging.

[0006] The technical scheme adopted by the present application is:

[0007] A large-scale impact type runner body forging composite compaction process, the specific steps are:

[0008] Step 1: match the ingot according to the runner forging process weight, the weight ratio of the forging to the ingot is 0.6-0.7; the ingot is integrally pre-elongated, the blanking is determined according to the forging heat and the punching loss material, the height-diameter ratio H / D is 2.0-2.1, the forging ratio is 1.25-1.35, and the forging temperature is 950-1150℃;

[0009] Step 2: full section upsetting compaction of the blank after pre-elongation in step 1, the height-diameter ratio D / H of the blank after upsetting is 1.2-1.3, the forging ratio is 1.7-2.0, and the forging temperature is 950-1220℃;

[0010] Step 3: use an upper flat anvil with a length greater than the diameter of the blank, the blank after upsetting in step 2 is rotated into the anvil for compaction around the center of the upper flat anvil, the reduction per pass is 10%-15% of the height before pressing, the height-diameter ratio D / H of the blank after pressing is 2.1-2.2, and the forging temperature is 950-1220℃;

[0011] Step four: turn the blank 90°, radial roll forging deformation is 15%-18%, forging temperature 950-1220℃;

[0012] Step five: turn the blank after step four 90°, adopt spinning anvil to spin into anvil from blank circumference to center direction, turn the blank 180° after each spinning to spin next time, each reduction is 12-15% of height before pressing, forging temperature 950-1220℃;

[0013] Step six: turn the spinning blank of step five 90° to carry out radial roll forging outside circle, eliminate bulge, radial roll forging deformation is 6%-10%, forging temperature 950-1220℃;

[0014] Step seven: according to process requirement, forge center groove on both end surface center of the roll circle blank of step six, and trim finished product, forging temperature 950-1150℃.

[0015] Due to the adoption of the technical scheme as above, the present application has the following advantages:

[0016] The present application realizes radial multiple deformation, matches larger anvil amount and reduction, is beneficial to weld internal casting defects, realizes integral, local and different step deformation by combining full cross-section upsetting, cross spinning anvil compaction and spinning anvil compaction in axial direction, matches different anvil amount and reduction, is beneficial to break and improve inclusion morphology, controls the trend of heart part into flaky inclusion, increases deformation amount by axial and radial alternating multiple deformation, welds internal defects, improves anisotropy characteristics of forgings, and improves comprehensive mechanical properties of forgings; forging two end surface center grooves realizes near net shape, guarantees metal streamline integrity and performance consistency; the whole process reduces fire times, improves forging efficiency, and has stable quality, strong impact resistance, and meets user requirement index. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is the blank schematic diagram after pre-drawing of the present application.

[0018] Figure 2 It is the blank schematic diagram after full cross-section upsetting of the present application.

[0019] Figure 3 It is the position schematic diagram of the upper anvil rotating crosswise in the diameter direction of the blank along the circumference in step three of the present application.

[0020] Figure 4 It is the schematic diagram of roll forging deformation in step four of the present application.

[0021] Figure 5is the position diagram of rotating into anvil in step five of the present application.

[0022] Figure 6 is the cross-sectional view diagram of the forged piece after forming.

[0023] In the figure: 1 - upper anvil, 2 - upper hammer head, 3 - rotary table, 4 - spinning anvil. DETAILED DESCRIPTION

[0024] The present application will be further explained in conjunction with the accompanying drawings and examples, which cannot limit the protection scope of the present application, and the purpose of disclosing the present application is to protect all technical improvements within the scope of the present application.

[0025] In conjunction with the accompanying drawings Figures 1-6 The present application is a large impact type runner body forging composite compaction process, and the specific steps are as follows:

[0026] Step one: according to the runner forging process weight 23t, 35T steel ingot is selected with weight ratio of 0.65, the steel ingot is integrally pre-drawn, the forging ratio is 1.28, the forging temperature is 950-1150℃, the ingot body is integrally pre-drawn to Ф1260×L, and the blank is determined according to the forging fire and the punching loss material: Ф1260×2575mm; the height-diameter ratio is 2.04; the pre-drawing improves the metal plasticity in the outer circle direction, and prevents the cracking of the stress state of the upset outer circle.

[0027] Step two: the blank after pre-drawing in step one is upset and compacted to H =1400 mm, D=Ф1710mm, the forging ratio is 1.8, 950-1220℃; the full-section upsetting increases the deformation, welds the casting defects, and also increases the cross-sectional area, providing a basis for subsequent deformation.

[0028] Step three: the upper anvil 1 with a length greater than the diameter of the blank is used, the blank after upsetting in step two is rotated into the anvil compacted by the upper anvil 1 around the center, and the blank is turned over 180° after each spinning to perform the next spinning, the first stroke is 170mm, the height after pressing is 1230mm; the second stroke is 150mm, the height after pressing is 1080mm; the third stroke is 130mm, the height after pressing is 950mm; the final blank size is H =950 mm, D=Ф2075mm, the forging ratio is 1.5, the forging temperature is 950-1220℃; the cross-rotating into the anvil fully utilizes the local deformation and different step deformation to crush and improve the morphology of inclusions, improves the compaction effect, increases the contact area of the blank and the hammer head, improves the forging efficiency, and reduces the fire times.

[0029] Step four: the blank is turned over 90° for radial roll forging deformation, the forging temperature is 950-1220℃, the blank size is H=1300mm, D=Ф1745mm, the forging ratio is 1.4; the radial deformation is increased by roll forging deformation, the inclusion morphology is improved, the inclusion which tends to be flaky after deformation is repaired, and the outer circle bulge is also controlled, which is beneficial to fine control of blank distribution.

[0030] Step five: the blank after step four is turned over 90°, the spinning anvil 4 is rotated into the anvil from the circumferential direction of the blank to the center direction for compaction, the blank is turned over 180° after each spinning to perform the next spinning, the first time the pressing amount is 190mm, the height after pressing is 1110mm; the second time the pressing amount is 170mm, the height after pressing is 940mm; the third time the pressing amount is 140mm, the height after pressing is 800mm; the fourth time the pressing amount is 120mm, the height after pressing is 680mm, the blank is turned over 180° after each spinning is completed, the forging temperature is 950-1220℃, and the forging ratio is 1.9; the high hydrostatic pressure in the center of the blank is realized, the inclusions are broken and improved in morphology by local deformation and different step deformation, and the trend of the core to become flaky inclusions is controlled.

[0031] Step six: the spinning blank after step five is turned over 90° for radial roll forging of the outer circle, and the bulge is eliminated, the forging temperature is 950-1220℃; the outer circle bulge is controlled, and fine control of blank distribution is realized.

[0032] Step seven: the center of the blank after step six is turned over 90° for radial roll forging of the outer circle, and the bulge is eliminated, the forging temperature is 950-1220℃; the outer circle bulge is controlled, and fine control of blank distribution is realized.

[0033] The part not described in detail in the present application is prior art.

[0034] In order to disclose the inventive purpose of the present application, the examples selected in the present application are currently considered to be appropriate, but it should be understood that the present application is intended to include all changes and improvements of the embodiments within the scope of the present application.

Claims

1. A large size impact type runner body forging composite compaction process characterized in that, The specific steps are: Step one: according to the weight matching of the runner forging process, the weight ratio of the forging to the ingot is 0.6-0.7; the ingot is pre-drawn as a whole, the blanking is determined according to the forging fire and the punching loss material, the height-diameter ratio H / D is 2.0-2.1, the forging ratio is 1.25-1.35, and the forging temperature is 950-1150℃; Step two: the blank after pre-drawing in step one is full-section upset and compacted, the diameter-height ratio D / H of the blank after upsetting is 1.2-1.3, the forging ratio is 1.7-2.0, and the forging temperature is 950-1220℃; Step three: the upper flat anvil with a length greater than the diameter of the blank is used, the blank after upsetting in step two is rotated around the center of the anvil to compact, the reduction per pass is 10%-15% of the height before pressing, the diameter-height ratio D / H of the blank after pressing is 2.1-2.2, and the forging temperature is 950-1220℃; Step four: the blank is turned over 90°, radial roll forging deformation is carried out, the radial roll forging deformation amount is 15%-18%, and the forging temperature is 950-1220℃; Step five: the blank after processing in step four is turned over 90°, the spinning anvil is used to rotate into the anvil from the circumference to the center of the blank, the blank is turned over 180° after each spinning to perform the next spinning, the reduction per pass is 12-15% of the height before pressing, and the forging temperature is 950-1220℃; Step six: the spinning blank in step five is turned over 90° and then radial roll forging is performed to eliminate the bulge, the radial roll forging deformation amount is 6%-10%, and the forging temperature is 950-1220℃; Step seven: the blank after rolling in step six is turned over 90°, the center groove is forged at both ends of the blank according to the process requirements, and the finished product is trimmed, and the forging temperature is 950-1150℃.

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