CN207567290U - On-line quenching device and production line for quenching and tempering heat treatment of steel pipe - Google Patents

Abstract

The utility model discloses an on-line quenching device and a production line for quenching and tempering heat treatment of steel pipes. The on-line quenching device includes an annular shell (3), and the inner surface of the annular shell (3) is provided with a plurality of flat nozzles (1) , the annular housing (3) is provided with a water inlet (31), and the annular housing (3) is provided with an inner flow channel (30) communicating with the flat mouth nozzle (1), and the cooling water can pass through the water inlet (31) in sequence ) and the inner runner (30) are ejected from the flat mouth nozzle (1) and are sheet-shaped, and the axis of the annular housing (3) is inclined relative to the plane where the sheet-shaped cooling water is located. The online quenching device and the production line for quenching and tempering heat treatment of steel pipes can replace the existing offline quenching, which greatly saves production costs; and improves the strength performance, reduces the proportion of unqualified quantities, and ensures that the cooling temperature of thick-walled pipes is greatly reduced, which is beneficial to follow-up Sawing and other processes greatly reduce the loss, and the online cooling control has remarkable economic benefits.

Description

On-line quenching device and steel pipe quenching and tempering heat treatment production line

technical field

The utility model relates to the field of heat treatment of steel pipes, in particular to an on-line quenching device and a production line for quenching and tempering heat treatment of steel pipes.

Background technique

For seamless steel pipes, annealing, normalizing, quenching, tempering, etc. are usually used for heat treatment to obtain the required properties. Quenching is a heat treatment process in which the seamless steel pipe is heated to a given temperature above the phase transition temperature, held for a certain period of time, and then rapidly cooled, in order to obtain martensite so that the required mechanical properties can be obtained after tempering at an appropriate temperature; Fire is a heat treatment process in which seamless steel pipes are heated to a temperature below the transformation temperature from austenite to pearlite, and then cooled to room temperature after proper heat preservation, in order to obtain the required structure and properties of seamless steel pipes; Strength and toughness, combining quenching and high temperature tempering, is called quenching and tempering heat treatment process. The usual quenching and tempering is carried out on a continuous step heat treatment production line including quenching furnace and tempering furnace, and offline quenching is used for quenching. The disadvantage is that the production efficiency is low.

Utility model content

In order to solve the problem of low production efficiency of steel pipe quenching and tempering heat treatment, the utility model provides an online quenching device and a production line for steel pipe quenching and tempering heat treatment, which can replace the existing offline quenching, greatly Save production cost; improve the strength performance, reduce the proportion of unqualified quantity, ensure that the cooling temperature of the thick-walled pipe is greatly reduced, which is beneficial to the subsequent sawing and other processes, greatly reducing the loss, online cooling control, and significant economic benefits.

The technical scheme that the utility model solves its technical problem adopts is:

An online quenching device, comprising at least one annular shell, the inner surface of the annular shell is provided with a plurality of flat mouth nozzles, the annular shell is provided with a water inlet, and the annular shell is provided with an inner flow channel communicating with the flat mouth nozzles , the cooling water can pass through the water inlet and the inner flow channel in sequence and then spray out from the flat nozzle in a sheet shape, and the axis of the annular housing is inclined relative to the plane where the sheet-shaped cooling water is located.

The annular shell is a circular structure, the section of the annular shell is rectangular, and a plurality of flat nozzles are arranged in regular rows and rows on the inner surface of the annular shell. Along the axial direction of the annular shell, all the flat nozzles The direction of injection is the same.

The flat mouth nozzle contains a sector section, a transition section, a twisted section and a threaded section connected in sequence. The flat mouth nozzle is threaded with the annular shell through the threaded section. The centerline of the threaded section is set along the radial direction of the annular shell. The flat mouth nozzle The injection port is located at one end of the sector, and the injection port is arc-shaped.

A production line for quenching and tempering heat treatment of steel pipes, comprising a first heating device, a piercing machine, a rolling and removing device, a sizing machine, a second heating device, a quenching device and a third heating device arranged in sequence, and the quenching device is the above-mentioned online quenching device.

The first heating device is an annular furnace or a walking furnace.

The rolling and stripping device is a continuous pipe rolling mill and stripping machine arranged in sequence, or the rolling and stripping device is a skew rolling mill, or the rolling and stripping device is a CPE pipe jacking machine and stripping machine arranged in sequence stick machine.

The second heating device is an induction heating device.

The beneficial effects of the utility model are: the online quenching device, the production line and the production process of steel pipe quenching and tempering heat treatment can replace the existing offline quenching, which greatly saves production costs; and improves the strength performance, reduces the proportion of unqualified quantities, and ensures thickness The cooling temperature of the wall tube is greatly reduced, which is beneficial to the subsequent sawing and other processes, so that the loss is greatly reduced, and the cooling is controlled online, and the economic benefits are remarkable.

Description of drawings

The accompanying drawings constituting a part of this application are used to provide a further understanding of the utility model, and the schematic embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute improper limitations to the utility model.

Figure 1 is an axonometric view of the overall structure of the on-line quenching device of the present invention.

Figure 2 is an isometric view of the annular housing.

Fig. 3 is a front view of the annular housing.

Fig. 4 is a sectional view of the annular housing.

Fig. 5 is a front view of a flat nozzle.

Fig. 6 is a perspective view of a flat mouth nozzle.

Fig. 7 is a structural schematic diagram of a production line for quenching and tempering heat treatment of steel pipes according to the utility model.

Fig. 8 is a flow chart of the production process of steel pipe quenching and tempering heat treatment according to the utility model.

1. Flat mouth nozzle; 2. Water inlet pipe; 3. Ring shell; 4. Hot steel pipe;

10. Injection port; 11. Sector section; 12. Transition section; 13. Twist section; 14. Thread section;

30, inner runner; 31, water inlet; 32, water outlet screw hole.

Detailed ways

It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The utility model will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

An online quenching device, comprising at least one annular shell 3, the inner surface of the annular shell 3 is provided with a plurality of flat mouth nozzles 1, the annular shell 3 is provided with a water inlet 31, and the annular shell 3 is provided with a flat The inner flow channel 30 connected to the mouth nozzle 1, the cooling water can pass through the water inlet 31 and the inner flow channel 30 in turn, and then spray out from the flat mouth nozzle 1 in a sheet shape, and the axis of the annular housing 3 is relative to the cooling water The plane where it is located is set at an inclination, as shown in Figure 1.

In this embodiment, the on-line quenching device may include a plurality of annular shells 3, each of which has the same size and structure, and the axes of each annular shell 3 coincide. During the quenching process, the hot steel pipe 4 travels along the direction A so as to be rapidly cooled to near the phase transition point (phase transition temperature). The online quenching device can replace the offline quenching device, thereby greatly saving production costs and improving production efficiency.

In this embodiment, the annular housing 3 has a circular structure, and the section of the annular housing 3 is rectangular. A plurality of flat mouth nozzles 1 are arranged in regular rows and rows on the inner surface of the annular housing 3, and along the annular housing 3 In the axial direction of the body 3, the spraying directions of all the flat nozzles 1 are the same, that is, the spraying directions of the flat nozzles 1 are all towards the outside of the paper of Figure 3, and it can also be understood that the spraying directions of the flat nozzles 1 are all towards Figure 4 to the right of the .

In this embodiment, the flat mouth nozzle 1 includes a sector section 11, a transition section 12, a screw section 13 and a threaded section 14 connected in sequence, and the flat mouth nozzle 1 is threaded with the water outlet screw hole 32 of the annular housing 3 through the threaded section 14. Connected, the center line of the threaded section 14 is set along the radial direction of the annular housing 3, the injection port 10 of the flat mouth nozzle 1 is located at one end of the segment 11, and the injection port 10 is arc-shaped, as shown in Figures 5 and 6.

In this embodiment, the water inlet 31 is externally connected with a water inlet pipe 2, and a plurality of flat-mouth nozzles 1 are arranged along the circumferential direction of the inner surface of the annular housing 3, and a plurality of flat-mouth nozzles 1 are arranged on the inner surface of the annular housing 3. Regularly arranged in fish scale layer, as shown in Figure 2 to Figure 4. The arc-shaped injection port 10 can spray cooling water in sheet form towards the inlet side of the hot steel pipe 4, as shown in FIG. 1 . The sector section 11 is inclined at a certain angle to the axis of the twisted section 13 and connected by a transition section 12 . The screwing section 13 is used to screw the threaded section 14 into the water outlet screw hole 32 of the annular housing 3 .

A production line for quenching and tempering heat treatment of steel pipes is introduced below. The production line for quenching and tempering heat treatment of steel pipes includes a first heating device, a piercing machine, a rolling and removing device, a sizing machine, a second heating device, a quenching device and a first heating device arranged in sequence. 3. A heating device, the quenching device is the above-mentioned online quenching device.

In this embodiment, the first heating device is a heating device such as an annular furnace or a walking furnace. The rolling and stripping device is a continuous pipe rolling mill and stripping machine arranged in sequence, or the rolling and stripping device is a skew rolling mill, or the rolling and stripping device is a CPE pipe jacking machine and stripping machine arranged in sequence stick machine. The second heating device may be an induction heating device capable of heating the steel pipe. The third heating device may also be an induction heating device capable of heating the steel pipe.

The production line for quenching and tempering heat treatment of steel pipes may also include a cooling bed, and the cooling bed is located behind the third heating device, that is, the production line for quenching and tempering heat treatment of steel pipes includes a first heating device, a piercer, a rolling mill, a pipe removing machine, The sizing machine, the second heating device, the quenching device, the third heating device and the cooling bed, as shown in Figure 7, the cooling bed is used to realize the air cooling process of the hot steel pipe. Or that is, the steel pipe quenching and tempering heat treatment production line includes a first heating device, a piercer, a skew rolling mill, a sizing mill, a second heating device, a quenching device, a third heating device and a cooling bed, or that the steel pipe quenching and tempering The heat treatment production line includes the first heating device, piercer, CPE pipe jacking machine, rod stripping machine, sizing machine, second heating device, quenching device, third heating device and cooling bed arranged in sequence.

The steel pipe quenching and tempering heat treatment production line can also be used to process steel pipes that are only quenched and not tempered, that is, for steel types that do not need quenching and tempering, it can be directly emptied. At this time, the third heating device does not work, that is, the steel pipe is quenched. No further heating after installation.

Introduce a kind of production technology of quenching and tempering heat treatment of steel pipe below, the production technology of described steel pipe quenching and tempering heat treatment adopts the above-mentioned production line of steel pipe quenching and tempering heat treatment, and this production technology comprises the following steps:

Step 1, heating the tube blank;

Step 2, perforation;

Step 3, rolling;

Step 4, take off the tube;

Step 5, sizing;

Step 6, quenching;

Step 7, tempering, as shown in Figure 8.

The following is a detailed description of the production process of the above steel pipe quenching and tempering heat treatment:

Step 1, heating the tube blank;

The tube blank enters the first heating device (such as a ring furnace), and the first heating device heats the tube blank to 1200 ° C ~ 1300 ° C to form a hot tube blank, and then transports the heated tube blank to the piercer;

Step 2, perforation;

The hot tube billet is pierced and rolled into a capillary tube by a piercing machine. During the piercing process, the temperature of the capillary tube is between 1100°C and 1200°C, and then the capillary tube is transported to a rolling mill (such as a continuous rolling mill);

Step 3, rolling;

The capillary tube is rolled into a blank tube by a rolling mill (such as a continuous rolling mill). During the rolling process, the temperature of the blank tube is between 950°C and 1050°C, and then the blank tube is transported to the stripping machine;

Step 4, take off the tube;

The tube stripping machine releases the blank tube from the mandrel, and then transports the blank tube to the sizing machine;

Step 5, sizing;

The blank pipe is sized on the sizing machine to obtain a hot finished pipe. During the sizing process, the temperature of the hot finished pipe is between 760°C and 860°C, because the wall thickness of the finished pipe may vary in temperature;

Step 6, quenching;

After the hot finished pipe comes out of the sizing machine, use a second heating device (such as an induction heating device) to heat the hot finished pipe to above 950°C; The hot finished tube is rapidly cooled to below 500°C;

Step 7, tempering;

After the online quenching is completed, use a third heating device (such as an induction heating device) to heat the finished hot tube to 650°C to 700°C, and then air cool the finished hot tube (air cooling can be realized with or without a cooling bed).

In the above-mentioned sizing process (step), the tension reduction process can be used. For steel types that do not need to be quenched and tempered, direct emptying can be adopted. At this time, no tempering process is required, that is, the steel pipe will not be heated after passing through the quenching device.

In the above step 6, when the hot finished tube is cooled from above 950°C to the transformation point temperature (phase transition temperature) of austenite, the online quenching device uses the first cooling rate to cool the hot finished tube, so that the hot finished tube The metallographic structure of the tube forms ferrite and pearlite; or adopts the second cooling rate to cool the hot finished tube, so that the metallographic structure of the hot finished tube forms bainite and ferrite; or adopts the third cooling rate to cool The hot finished pipe makes the metallographic structure of the hot finished pipe form martensite; the third cooling rate is greater than the second cooling rate, and the second cooling rate is greater than the first cooling rate. The specific values of the first cooling rate, the second cooling rate, and the third cooling rate can be obtained through multiple experimental measurements.

That is, in the above step 6, when the A structure (austenite) of the hot finished pipe is cooled to near the dynamic phase transformation point, the first cooling rate is used to obtain the F+P structure (ferrite+pearlite); the second cooling rate is used The cooling rate is used to obtain the B+F structure (bainite + ferrite); the third cooling rate is used to obtain the M structure (martensite).

The above is only a specific embodiment of the utility model, and it cannot limit the scope of utility model implementation, so the replacement of its equivalent components, or the equivalent changes and modifications made according to the patent protection scope of the utility model should still belong to areas covered by this patent. In addition, the technical features and technical features, technical features and technical solutions, and technical solutions and technical solutions in the utility model can be used in free combination.

Claims (7)

1. a kind of press quenching device, which is characterized in that the press quenching device includes at least one toroidal shell (3), ring The inner surface of shape housing (3) is equipped with multiple flat mouth nozzles (1), and toroidal shell (3) is equipped with water inlet (31), toroidal shell (3) It is interior equipped with the inner flow passage (30) connected with flat mouth nozzle (1), cooling water can pass through water inlet (31) and inner flow passage (30) successively It is sprayed afterwards from flat mouth nozzle (1) and in the form of sheets, the axis of toroidal shell (3) inclines relative to the plane where the cooling water of the sheet Tiltedly setting.

2. press quenching device according to claim 1, which is characterized in that toroidal shell (3) is cirque structure, annular The section of housing (3) is rectangular, and multiple flat mouth nozzles (1) are staggered in the ranks of rule in the inner surface of toroidal shell (3), Along the axis direction of toroidal shell (3), the injection direction all same of all flat mouth nozzles (1).

3. press quenching device according to claim 1, which is characterized in that flat mouth nozzle (1) contains sequentially connected fan Shape section (11), changeover portion (12), twist-on section (13) and thread segment (14), flat mouth nozzle (1) pass through thread segment (14) and circular casing Body (3) is threadedly coupled, and the center line of thread segment (14) is set along the radial direction of toroidal shell (3), the jet port of flat mouth nozzle (1) (10) positioned at one end of fan-shaped section (11), jet port (10) is arc.

4. a kind of production line of steel pipe Tempering and Quenching, which is characterized in that the production line of the steel pipe Tempering and Quenching contains successively The first heater of setting, punch, rolling and de- pipe device, sizing mill, secondary heating mechanism, quenching unit and third add Thermal, the quenching unit are the press quenching device described in any one in claims 1 to 3.

5. the production line of steel pipe Tempering and Quenching according to claim 4, which is characterized in that the first heater is ring Shape stove or stepping furnace.

6. the production line of steel pipe Tempering and Quenching according to claim 4, which is characterized in that the rolling and de- pipe device are Either the rolling and de- pipe device are skew rolling mill or the rolling and de- pipe device to the tandem rolling tube machine and winding arbor extraction press set gradually For the CPE push-bench and rod stripping machine set gradually.

7. the production line of steel pipe Tempering and Quenching according to claim 4, which is characterized in that the secondary heating mechanism is sense Answer heating unit.