CN-121988691-A - Cold heading manufacturing process of titanium alloy flange screw

CN121988691ACN 121988691 ACN121988691 ACN 121988691ACN-121988691-A

Abstract

The invention discloses a method for manufacturing a screw rod, which comprises the following steps of S1, S2, cold heading manufacturing, a, blank pre-heading, b, flange surface pre-forming, c, screw rod diameter reduction and head finishing, d, final heading forming, e, auxiliary forming, S3, heat treatment strengthening, S4, thread machining and S5, and surface treatment. According to the invention, the spray heads are arranged among stations of the cold header, and the opposite-injection type photoelectric sensor, the electromagnetic valve, the time relay, the spraying machine and the cold header are linked through the programmable logic controller to realize full-automatic closed-loop control, so that manual intervention is not needed, an operation error is avoided, the production continuity is improved, meanwhile, the oil-based lubricant is sprayed on the surface of the blank, the cold header deformation resistance of the titanium alloy blank is reduced, the adhesion of the die blank is reduced, the screw forming integrity is ensured, and the defects such as cracks are avoided.

Inventors

YU GENWEN
WU TUJIN

Assignees

苏州博特星机械设备有限公司

Dates

Publication Date: 20260508
Application Date: 20260311

Claims (6)

1. The cold heading manufacturing process of the titanium alloy flange screw is characterized by comprising the following steps of: S1, raw material pretreatment; a, selecting a titanium alloy cold heading special wire rod, wherein the diameter of the wire rod is matched with the nominal size of a screw rod part; Acid washing to remove oxide skin and greasy dirt on the surface of the wire rod, and phosphating and saponifying the wire rod; Straightening the wire rod by a straightening machine, and cutting the wire rod into a fixed-length blank according to the total length of the flange screw by a cutting mechanism of a cold header; S2, cold heading manufacturing; a, blank pre-upsetting, namely feeding the blank into a first station female die for positioning by a cold header feeding mechanism, driving a first station punch to quickly descend by a main transmission slide block under the drive of a crankshaft connecting rod mechanism, applying axial pressure to one end of the blank, completing pre-upsetting, upsetting the end part of the blank into a flange screw head embryonic form, and primarily shaping the diameter and thickness of the head; The flange surface preforming, namely, the pre-headed blank is clamped by a transfer clamp, is precisely transferred to a second station along a transfer guide rail, is embedded into a second station die for positioning, a main transmission slide block drives a punch of a special die cavity of the second station flange surface to descend, performs secondary upsetting on the head blank, the special flange die cavity of the punch is matched with the die, the outer diameter and the thickness of the flange surface are preliminarily formed, and a die positioning mechanism can finely adjust the coaxiality of the punch and the die to ensure the preformed symmetry of the flange surface; The blank is sent to a third station through a transfer mechanism, the non-upsetting part of the blank stretches into a cavity die of a reducing cavity of the third station, a main transmission sliding block drives a finishing punch to move downwards, on one hand, the reducing cavity of the die is used for reducing the rod part of the blank, the size of the rod part is accurately compressed to the nominal diameter of the screw, the original diameter tolerance of a wire rod is eliminated, and the size consistency of the screw is ensured; d, final upsetting forming, namely feeding the semi-finished product in the front of the final upsetting punch and the final upsetting female die into a fourth station by a transfer mechanism, driving a main transmission die clamping mechanism to accurately clamp the dies, enabling a hexagonal cavity of the punch, a finishing cavity of a flange surface and a screw end cavity of the female die to cooperate, and performing final upsetting extrusion on the flange surface of the head, the hexagonal of the head and the screw end of the screw, wherein all structures except screw threads of the flange screw are formed at one time, and after forming, ejecting a finished product from the female die by a material ejecting mechanism through a material ejecting pin and a material ejecting rod; e, auxiliary forming, namely transferring the semi-finished product subjected to final upsetting to an additional auxiliary station, extruding and chamfering the end part of the screw by a chamfering punch of an auxiliary forming die, and carrying out fillet forming on the flange surface and the connecting root part of the screw by a root fillet cavity; Spray heads are arranged between the first work station and the second work station, between the second work station and the third work station and between the third work station and the fourth work station, a transmitting end and a receiving end of an opposite-emission photoelectric sensor are respectively arranged between the work stations and at two sides of the spray heads, oil-based lubricating oil is sprayed on the surface of a blank through a spraying machine, one side of each spray head is provided with a time relay, each spray head is connected with a spraying machine conveying main pipe filled with the oil-based lubricating oil through a corresponding conveying branch pipe, a one-way valve is arranged at the joint of the conveying branch pipe and the spraying machine conveying main pipe, each conveying branch pipe is provided with an electromagnetic valve, and the opposite-emission photoelectric sensor, the electromagnetic valve, the time relay, the spraying machine and a heading machine are all in electric signal connection with a controller; When the blank blocks the light path between the transmitting end and the receiving end of the correlation photoelectric sensor, and the receiving end cannot receive the light signal, the controller controls the cold header to stop running and the feeding mechanism to stop conveying the blank, and simultaneously, the controller controls the electromagnetic valve, the time relay and the spraying machine corresponding to the conveying branch pipe to be opened, the spraying machine sprays oil-based lubricating oil to the surface of the static blank through the spray head, and the time relay starts timing; h, when the timing duration of the time relay reaches a set value, resetting the time relay and waiting for the next trigger, simultaneously controlling the electromagnetic valve and the spraying machine of the corresponding conveying branch pipe to be closed by the controller, and controlling the cold header to restart, and continuously conveying blanks by the feeding mechanism of the cold header; s3, heat treatment strengthening, namely neatly placing a semi-finished product subjected to thread processing on a material tray of a vacuum furnace, heating the vacuum furnace to 600-700 ℃ at the speed of 11-13 ℃ per minute, preserving heat for 1-2h, cooling the vacuum furnace to room temperature along with the furnace, quickly heating the annealed product to 930-940 ℃, controlling the heating speed to 25-30 ℃ per minute, preserving heat for 1h, immediately quenching the quenched product after heat preservation, heating the quenched product to 485-495 ℃ at the heating speed of 16-18 ℃ per minute, preserving heat for 5-5.5h, and cooling the annealed product to room temperature in air after heat preservation is finished; s4, thread processing, namely processing threads on the screw rod blank subjected to cold heading forming by adopting a thread rolling or thread rolling process; And S5, surface treatment, namely removing greasy dirt and oxide skin on the surface of the product through ultrasonic cleaning, performing heat treatment on salting, and putting the cleaned product into a hot air circulation oven to thoroughly remove surface moisture.
2. The cold heading manufacturing process of the titanium alloy flange screw according to claim 1, wherein in the step S2, the spray head is a fan-shaped atomizing nozzle, the spraying angle is 70-80 degrees, and the vertical distance between the nozzle and the surface of the blank is 10-12mm.
3. The cold heading manufacturing process of the titanium alloy flange screw according to claim 2, wherein in the step S2, sealing gaskets are arranged at the joint of the branch pipe, the spray head and the electromagnetic valve, and the output pressure of the spraying machine is 0.32-0.42MPa.
4. The cold heading manufacturing process of the titanium alloy flange screw according to claim 3, wherein in the step S2, the correlation photoelectric sensor is an infrared high-sensitivity sensor, the response time is less than or equal to 0.1S, the detection distance is 90-100mm, the set timing duration of the time relay is 5-6S, the static residence time of the blank below the spray head is not less than the spraying duration, the controller is arranged in a control cabinet of the cold heading machine, and the controller is a programmable logic controller.
5. The cold heading process for manufacturing a titanium alloy flange screw according to claim 1, wherein in S5, a hot air circulation oven is dried at 92-94 ℃ for 40-45min.
6. The cold heading manufacturing process of the titanium alloy flange screw according to claim 1, wherein in the step S2, a lubricating oil recovery groove is arranged below the spray head, the recovery groove is connected with an oil storage cavity of the spraying machine through a return pipe, and a filter valve is arranged on the return pipe and is used for filtering and recovering impurities in the lubricating oil and recycling the impurities.

Description

Cold heading manufacturing process of titanium alloy flange screw Technical Field The invention relates to the technical field of cold heading manufacturing of titanium alloy flange screws, in particular to a cold heading manufacturing process of titanium alloy flange screws. Background The cold heading process for producing flange screw of titanium alloy includes applying axial pressure to the blank of titanium alloy wire or bar with special cold heading equipment and precise mold at room temperature to make the blank deform plastically in the mold cavity, and forming the head of flange screw and the screw in one step. Most of the existing cold header only adopts oil dripping, brushing or spraying at a fixed position at a single station, independent spray heads are not arranged among stations, accurate lubrication cannot be realized on key nodes of multi-station deformation of a titanium alloy blank, insufficient lubrication coverage is caused, deformation resistance is increased during cold header of the blank, die blank adhesion is easy to occur, and then defects such as cracks are caused, so that screw forming integrity is reduced. Therefore, we propose a cold heading manufacturing process of titanium alloy flange screws to solve the above problems. Disclosure of Invention The invention aims to solve the defects in the prior art, and provides a cold heading manufacturing process of a titanium alloy flange screw. A cold heading manufacturing process of a titanium alloy flange screw comprises the following steps: S1, raw material pretreatment; a, selecting a titanium alloy cold heading special wire rod, wherein the diameter of the wire rod is matched with the nominal size of a screw rod part; Acid washing to remove oxide skin and greasy dirt on the surface of the wire rod, and phosphating and saponifying the wire rod; Straightening the wire rod by a straightening machine, and cutting the wire rod into a fixed-length blank according to the total length of the flange screw by a cutting mechanism of a cold header; S2, cold heading manufacturing; a, blank pre-upsetting, namely feeding the blank into a first station female die for positioning by a cold header feeding mechanism, driving a first station punch to quickly descend by a main transmission slide block under the drive of a crankshaft connecting rod mechanism, applying axial pressure to one end of the blank, completing pre-upsetting, upsetting the end part of the blank into a flange screw head embryonic form, and primarily shaping the diameter and thickness of the head; The flange surface preforming, namely, the pre-headed blank is clamped by a transfer clamp, is precisely transferred to a second station along a transfer guide rail, is embedded into a second station die for positioning, a main transmission slide block drives a punch of a special die cavity of the second station flange surface to descend, performs secondary upsetting on the head blank, the special flange die cavity of the punch is matched with the die, the outer diameter and the thickness of the flange surface are preliminarily formed, and a die positioning mechanism can finely adjust the coaxiality of the punch and the die to ensure the preformed symmetry of the flange surface; The blank is sent to a third station through a transfer mechanism, the non-upsetting part of the blank stretches into a cavity die of a reducing cavity of the third station, a main transmission sliding block drives a finishing punch to move downwards, on one hand, the reducing cavity of the die is used for reducing the rod part of the blank, the size of the rod part is accurately compressed to the nominal diameter of the screw, the original diameter tolerance of a wire rod is eliminated, and the size consistency of the screw is ensured; d, final upsetting forming, namely feeding the semi-finished product in the front of the final upsetting punch and the final upsetting female die into a fourth station by a transfer mechanism, driving a main transmission die clamping mechanism to accurately clamp the dies, enabling a hexagonal cavity of the punch, a finishing cavity of a flange surface and a screw end cavity of the female die to cooperate, and performing final upsetting extrusion on the flange surface of the head, the hexagonal of the head and the screw end of the screw, wherein all structures except screw threads of the flange screw are formed at one time, and after forming, ejecting a finished product from the female die by a material ejecting mechanism through a material ejecting pin and a material ejecting rod; e, auxiliary forming, namely transferring the semi-finished product subjected to final upsetting to an additional auxiliary station, extruding and chamfering the end part of the screw by a chamfering punch of an auxiliary forming die, and carrying out fillet forming on the flange surface and the connecting root part of the screw by a root fillet cavity; Spray heads are arranged between the first work st