WO2019010866A1

WO2019010866A1 - Long valve body punching, elongating, and forging process

Info

Publication number: WO2019010866A1
Application number: PCT/CN2017/108402
Authority: WO
Inventors: 高欣; 高明; 邱亚军; 高汝峰
Original assignee: 江阴南工锻造有限公司
Priority date: 2017-07-13
Filing date: 2017-10-30
Publication date: 2019-01-17
Also published as: CN107363214B; CN107363214A

Abstract

A long valve body punching, elongating, and forging process comprising the following steps: heating a blank to 1220°C, thermally insulating for 9 hours, using an upper flatbed and a lower turntable for primary upsetting, primary elongating, and secondary upsetting of the blank to 1320 mm × 1040 mm and 1200 mm in height, and returning to a furnace; using a die punch for punching, flipping, using the die punch for punching through and cutting off a core material, and returning to the furnace; using secondary punching for elongating to 1450 mm in length, withdrawing the punching die after shaping, and returning to the furnace; using a shaping core rod for elongating to position, and finishing a square body for forming. The forging process increases the tightness of the core portion of a product, extends the service life of the product, and reduces processing costs and processing cycles.

Description

Long valve body punching and lengthening forging process

Technical field

The invention relates to the technical field, in particular to a long valve body punching and lengthening forging process.

Background technique

Long valve body blank (as shown in Figure 1), the length exceeds the width and thickness. This type of valve body is blanked into square punching holes. Due to the long length, the forging size can be ensured by subsequent lengthening, but the forging center is drawn after lengthening. The hole is easily deformed into an elliptical or irregular diamond shape, which not only fails to achieve the purpose of material saving, but also causes machining difficulties, waste of labor and tools, and serious even because the inner hole is too deformed, resulting in insufficient amount of waste, so the type has been used in the past. The forging of the valve body is made into a square, and the middle hole is machined by subsequent machining.

The above conventional forging schemes have large machining allowance and high processing cost (the inner hole needs to be bottomed and then processed through the boring, the machining cost is high, the machining cycle is long), and the cost control and delivery time are There are serious deficiencies that are not attractive to customers.

There is an urgent need to design a more effective forging process for this type of product.

Summary of the invention

The technical problem to be solved by the invention is as follows: firstly, the cost is reduced and the market competitiveness is improved; secondly, the central hole of the square punching forging is easily deformed into an elliptical or irregular diamond shape, which leads to difficulty in machining or insufficient margin to cause the product to be scrapped.

In order to solve the above technical problem, the present invention provides a long valve body punching and lengthening forging process, comprising the following steps:

S1: heating the billet to 1220 ° C, holding for 9 hours, using the upper plate, the lower turntable, the blank is upset to 850 mm high;

S2: lengthen to 1060mm × 780mm square at a time, 2000mm long;

S3: The second upset is up to 1320mm×1040mm, 1200mm high, and is returned to the furnace;

S4: punching with a head punch, turning over the surface, punching through the head and cutting the core material, and returning to the furnace;

S5: Use a second punch to pull up to 1450mm long, and then take out the punch after shaping and return to the furnace;

S6: Use the forming mandrel to lengthen it in place and finish it.

The formed mandrel is φ260/φ210×2000 mm long. (Note: The original mandrel design is equipped with a pliers, and the present invention improves the original mandrel production design, and the mandrel has no pliers.)

Preferably, in the S3, the furnace temperature is 1220 ° C, and the temperature is kept for 5 hours.

Preferably, in the S4, the head punch size is: a large end φ330 mm, a small end φ300 mm, and a length of 800 mm.

Preferably, in the S4, the furnace temperature is 1220 ° C, and the temperature is kept for 3 hours.

Preferably, in the S5, the size of the two punches is: large end φ260 mm, small end φ210 mm, and length 1500 mm.

Preferably, in the S5, the furnace temperature is 1200 ° C, and the temperature is kept for 2 hours.

Preferably, in the S6, the amount of reduction is uniform during the finishing, and the inner hole is rounded.

Preferably, in the S1 to S3, the pier has a thickness ratio of 4.5 and a draw length ratio of 4.7.

The advantages of the invention are:

1. The punching and forging process is adopted to improve the tightness of the core of the product, and the mechanical properties of the subsequent body of the product are obviously improved, and the service life of the product is prolonged;

2. Reduced processing costs and processing cycles, increasing market appeal.

DRAWINGS

Figure 1. Schematic diagram of the structure of a long valve body blank.

Detailed ways

The specific embodiments provided by the present invention will be described in detail below with reference to the embodiments.

Example 1

The long valve body punching and lengthening forging process of the invention, wherein:

1. The blank is as high as possible, the length of the blank is reduced, and the mandrel is taken out in time during the lengthening process to prevent the temperature of the mandrel from being too high to deform and unable to pull out the mandrel;

2. Tooling improvement: a) Make the head punch, the outer diameter of the head punch is large, and it is convenient for the two punches to be placed;

b) making a second flush, the intermediate transition is long;

c) Make long rods, which are finally lengthened and finished.

Specifically, the following steps are included:

For the blank of Fig. 1, the blanking is 13200 kg; the head of the batch forging steel ingot is 1105 mm/tail size 1000 mm, and the ingot is 1940 mm long octagonal ingot.

S2: lengthen to 1060mm × 780mm square at a time, 2000mm long;

S3: The second upset is up to 1320mm×1040mm, 1200mm high, and the furnace is returned to the furnace (the furnace temperature is 1220°C, and the heat preservation is 5 hours);

S4: use the head punch (two total, punch size: big end ∮330mm, small end φ300mm, length 800mm) for punching, turning over, punching and cutting the core material with the head, returning to the furnace (furnace temperature 1220 ° C, insulation 3 hours out);

S5: Use two punches to lengthen up to 1450mm long (punch size: big end φ260mm, small end φ210mm, length 1500mm), after the shaping, take out the punch and return to the furnace (furnace temperature 1200 °C, heat preservation 2 hours);

S6: Use the forming mandrel to lengthen it in place, and finish the square body forming (the amount of pressing is uniform during finishing, and the inner hole is rounded).

The preferred embodiments of the present invention have been specifically described above, but the present invention is not limited to the embodiments, and those skilled in the art can make various equivalents without departing from the inventive spirit of the present invention. Modifications or substitutions of the invention are intended to be included within the scope of the appended claims.

Claims

A long valve body punching and lengthening forging process, characterized in that the method comprises the following steps:

S1: heating the billet to 1220 ° C, holding for 9 hours, using the upper plate, the lower turntable, the blank is upset to 850 mm high;

S2: lengthen to 1060mm × 780mm square at a time, 2000mm long;

S3: The second upset is up to 1320mm×1040mm, 1200mm high, and is returned to the furnace;

S4: punching with a head punch, turning over the surface, punching through the head and cutting the core material, and returning to the furnace;

S5: Use a second punch to pull up to 1450mm long, and then take out the punch after shaping and return to the furnace;

S6: Use the forming mandrel to lengthen it in place and finish it.
The long valve body punching and forging process according to claim 1, wherein in the S3, the furnace temperature is 1220 ° C, and the furnace is heated for 5 hours.
The long valve body punching and drawing forging process according to claim 1, wherein in the S1 to S3, the pier has a thickness ratio of 4.5 and a draw length ratio of 4.7.
The long valve body punching and lengthening forging process according to claim 1, wherein in the S4, the size of the head punch is: a large end φ330 mm, a small end φ300 mm, and a length of 800 mm.
The long valve body punching and drawing forging process according to claim 1, wherein in the S4, the furnace temperature is 1220 ° C, and the heat is kept for 3 hours.
The long valve body punching and drawing forging process according to claim 1, wherein in the S5, the size of the two punching punches is: a large end φ260 mm, a small end φ210 mm, and a length 1500 mm.
The long valve body punching and drawing forging process according to claim 1, wherein in the S5, the furnace temperature is 1200 ° C, and the heat is kept for 2 hours.
The long valve body punching and drawing forging process according to claim 1, wherein in the S6, the amount of pressing is uniform during the finishing, and the inner hole is rounded.