CN115589715A - SMT double-process production method - Google Patents

Abstract

The invention discloses a SMT double-process production method, which comprises the following steps: S1: printing solder paste on the component pad, printing and coating a quantitative amount of solder paste on the pad; S2: printing red glue in the middle of the pad , apply a certain amount of red glue printing on the middle position above the pad; S3: make a half-engraved red glue steel mesh; S4: SMT, carry out the SMT operation of multiple groups of electronic components according to the requirements of the drawing; S5: pass the reflow oven . This SMT double-process production method, in the SMT production, print solder paste on the pad first, fix the solder paste on the solder paste stencil, and then print red glue in the middle of the pad, and the red glue stencil is half-cut to avoid the printed Solder paste, and then attach the end of the solder leg of the electronic component to the pad on the PCB board, and process the completed PCB board through a reflow furnace, so that the red glue is solidified and fixed to the SMT parts, and the solder paste is melted to weld the SMT Parts, since the parts have been tinned and welded during SMT production, the SMT parts will not appear empty welding when the plug-in passes through the tin furnace.

Description

A kind of production method of SMT double process

technical field

The invention relates to the technical field of SMT production, in particular to an SMT double-process production method.

Background technique

SMT is a circuit assembly technology that mounts non-lead or short-lead surface mount components on the surface of a substrate or the surface of other substrates, and solders and assembles them by reflow soldering or dip soldering. SMT is the most popular technology and process in the electronic assembly industry, and it is a relatively popular technology in the electronic assembly industry. When various electronic components are patch-welded on the PCB board according to the requirements of the drawings, it is necessary to perform welding processing through the SMT process.

The SMT process generally adopts a single red glue or solder paste process. In the production process of the red glue process, after the product passes through the tin furnace, there will be a phenomenon of empty soldering of the SMT parts, which makes the soldering of the electronic components on the board unstable and cannot meet the use requirements. .

Contents of the invention

The purpose of the present invention is to provide a kind of SMT double-process production method, to solve the SMT process that the above-mentioned background technology proposes generally adopts single red glue or solder paste process, in the production process of red glue process, after the product passes tin furnace, can appear The problem of empty welding of SMT parts.

In order to achieve the above object, the present invention provides the following technical solutions: a production method of SMT double process, comprising the following steps:

S1: Print solder paste on the pad of the part, and print and apply a certain amount of solder paste on the pad;

S2: Print red glue in the middle of the pad, and apply a certain amount of red glue to the middle position above the pad;

S3: Making half engraved red plastic steel mesh;

S4: SMT, multiple groups of electronic components are placed in accordance with the requirements of the drawing;

S5: Through the reflow furnace, process the finished PCB board through the reflow furnace.

Preferably, the solder paste described in step S1 is printed with a thickness of 0.12mm on the upper surface of the component pad.

Preferably, the red glue described in step S2 is printed with a thickness of 0.35 mm at the upper middle position of the component pad.

Preferably, the stencil described in step S3 is divided into a solder paste stencil and a red glue stencil, the solder paste is fixed on the solder paste stencil, and the red glue stencil is set as a half-cut structure to avoid the printed solder paste .

Preferably, the patching in step S4 is to patch and correspond the soldering leg ends of the electronic components to the pads on the PCB.

Preferably, in step S5, the red glue on the pad is solidified and the electronic components are fixed by high-temperature processing in a reflow furnace, and the electronic components are welded by melting the solder paste.

Compared with the prior art, the beneficial effect of the present invention is: the production method of the SMT double process, first print solder paste on the pad during SMT production, fix the solder paste on the solder paste stencil, and then print red in the middle of the pad Glue, red glue stencil to avoid the printed solder paste for half a moment, and then attach the end of the solder leg of the electronic component to the pad on the PCB board, and process the completed PCB board through a reflow furnace. In this way, the red glue is solidified to fix the SMT parts, and the solder paste is melted to weld the SMT parts. Since the parts have been tinned and welded during SMT production, the SMT parts will not be empty-welded when the plug-in passes through the tin furnace.

Description of drawings

Fig. 1 is a schematic flow chart of the present invention;

Fig. 2 is a schematic diagram of the principle of the present invention;

Fig. 3 is a schematic diagram of the main view structure of the present invention;

Fig. 4 is a schematic diagram of a right-side cross-sectional structure of the present invention.

In the figure: 1. PCB board; 2. Electronic components; 3. Solder pad; 4. First stencil; 5. Solder paste; 6. Second stencil; 7. Groove; 8. Red glue.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1-2, the present invention provides a kind of technical scheme: a kind of production method of SMT double process, comprises the following steps:

S1: Print solder paste 5 on the pad 3 of the part. During SMT production, print and coat a certain amount of solder paste 5 on the pad 3. The thickness of the solder paste 5 printed on the surface above the pad 3 of the part is 0.12mm,;

S2: Print red glue 8 in the middle of the pad 3, print and coat a certain amount of red glue 8 on the middle position above the pad 3, and the printing thickness of the red glue 8 on the middle position above the pad 3 of the part is 0.35mm;

S3: Make a half engraved red glue stencil, the stencil is divided into solder paste stencil and red glue stencil, fix solder paste 5 on the solder paste stencil, and set the red glue stencil as a half engraved structure to avoid Printed solder paste 5;

S4: patching, multiple groups of electronic components 2 are placed according to the requirements of the drawing, and the patching is to match the end of the soldering leg of the electronic component 2 with the pad 3 on the PCB board 1;

S5: Pass the reflow furnace, process the PCB board 1 that has been patched through the reflow furnace, and the reflow furnace cures the red glue 8 on the pad 3 to fix the electronic component 2 through high temperature processing, and the solder paste 5 melts and welds electronic components2.

In specific implementation, during SMT production, first print solder paste 5 on the pad 3 of the part, and then print red glue 8 in the middle of the pad 3. The red glue stencil is used for half a moment to avoid the printed solder paste 5, and then paste After passing through the reflow furnace, the red glue 8 solidifies and fixes the SMT parts, and the solder paste 5 melts and welds the SMT parts. Since the parts have been tinned and welded during SMT production, the SMT parts will not have empty soldering when the plug-in passes through the tin furnace, thereby reducing Maintenance rate, improve the quality and production efficiency of the whole welding process.

Example

Referring to Figures 3-4, it can be seen that a production method of SMT double process includes a PCB board 1 and a pad 3, the upper surface of the PCB board 1 is fixed with a plurality of electronic components 2, and the PCB board 1 is close to the electronic components 2 is provided with a pad 3, the upper end of the pad 3 is provided with a first stencil 4, the upper end of the first stencil 4 is fixed with solder paste 5, and the upper end of the first stencil 4 A second stencil 6 is also provided, the lower end of the second stencil 6 is provided with a groove 7 corresponding to the solder paste 5 , and the upper end of the second stencil 6 is fixed with red glue 8 .

The first stencil 4 is a solder paste stencil, the second stencil 6 is a red glue stepped stencil, and the thickness of the second stencil 6 is greater than the thickness of the first stencil 4, and the groove 7 The depth is greater than the printing thickness of the solder paste 5, the printing thickness of the solder paste 5 is 0.12 mm, and the printing thickness of the red glue 8 is 0.35 mm.

When printing, print the red glue 8 first, and then print the solder paste 5, which can prevent the printed solder paste 5 from being damaged. The SMT production patch goes through the reflow furnace, the red glue 8 solidifies and fixes the parts, and the solder paste 5 melts and welds the parts. After the DIP station completes the packaging, it passes through the wave soldering equipment, so that the solder joints of the SMT electronic parts are free from poor soldering, thereby effectively improving product quality and personnel efficiency.

To sum up, during SMT production, print and apply 0.12mm solder paste 5 on the pad 3, print and apply 0.35mm red glue 8 on the middle position above the pad 3, and fix the solder paste stencil Solder paste 5, and set the red plastic stencil as a half-engraved structure to avoid the printed solder paste 5. By matching the end of the soldering leg of the electronic component 2 with the pad 3 on the PCB board 1, it will be completed The PCB board 1 of the chip is processed through the reflow furnace, so that the reflow furnace can cure the red glue 8 on the pad 3 to fix the electronic component 2 through high-temperature processing, and solder the electronic component 2 by melting the solder paste 5, so that the SMT parts are processed Stable welding, avoiding the phenomenon of empty soldering, the SMT dual-process production method uses red glue plus solder paste dual-process technology to solve the current standard in the production process that uses a single red glue process to pass through the tin furnace, and there will be empty welding of parts. The dual-process technology of red glue and solder paste can solve the undesirable phenomenon of over-tin and empty soldering and improve product quality. The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or perform equivalent replacements for some of the technical features. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (6)

1. The production method of the SMT dual process is characterized by comprising the following steps:

s1: printing solder paste (5) on the part bonding pad (3), and printing and coating a certain amount of solder paste (5) above the bonding pad (3);

s2: printing red glue (8) in the middle of the bonding pad (3), and printing and coating quantitative red glue (8) at the middle position above the bonding pad (3);

s3: manufacturing a semi-red glue etching steel mesh;

s4: the method comprises the following steps of (1) pasting, wherein multiple groups of electronic elements (2) are pasted according to the drawing requirements;

s5: and (4) passing through a reflow oven, and processing the PCB (1) with the surface mounted by the reflow oven.

2. An SMT dual process production method according to claim 1, wherein: and (2) printing the solder paste (5) with the thickness of 0.12mm on the upper surface of the part bonding pad (3) in the step (S1).

3. An SMT dual process production method according to claim 1, wherein: and the printing thickness of the red glue (8) in the step S2 is 0.35mm at the middle position above the part bonding pad (3).

4. An SMT dual process production method according to claim 1, wherein: and the steel mesh in the step S3 is divided into a solder paste steel mesh and a red glue steel mesh, solder paste (5) is fixed on the solder paste steel mesh, and the red glue steel mesh is arranged to be of a half-etching structure to avoid the printed solder paste (5).

5. An SMT dual process production method according to claim 1, wherein: and in the step S4, the end part of the welding leg of the electronic element (2) is pasted and corresponds to the welding pad (3) on the PCB (1).

6. An SMT dual process production method according to claim 1, wherein: and in the step S5, the reflow furnace solidifies the red glue (8) on the bonding pad (3) through high-temperature processing to fix the electronic element (2), and the solder paste (5) melts and welds the electronic element (2).

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