IPC 7711A.pdf - 第142页
NOTES IPC-771 1A Number: 3.10.4 Revision: Date: 2/98 Subject: PLCC Socket Removal P a g e2o f2 Copyright Association Connecting Electronics Industries Provided by IHS under license with IPC Not for Resale No reproduction…
EQUIPMENT REQUIRED
Hot air pencil
Hot air tip
Needle nose pliers
Knife
OPTIONAL EQUIPMENT
Desoldering station
MATERIALS
Flux-cored solder
Flux
Cleaning solvent
PROCEDURE
1. Remove conformal coating (if any) and clean work area of any contamination,
oxides or residues.
2. Cut and remove plastic center. (See Figure 1.)
3. Install appropriate hot air tip into the hot air pencil.
4. Set heater temperature to approximately 425°C and adjust as necessary.
5. Adjust pressure output so hot air scorches a tissue from approximately 0.5 cm
away.
6. Position tip approximately 0.5 cm away from inside area of socket. Rotate hot air
pencil in a circular motion around lands until complete solder melt is observed.
(See Figure 2.)
7. Approximately 5 to 8 seconds after solder melt occurs, begin lifting the socket
very gently and only a little at a time until the socket becomes detached. (See
Figure 3.) This entire step should take approximately 45 seconds.
8. After solder melt occurs, clean and inspect as required.
CAUTION:
This method is not recommended unless there are no other options.
PWB will be subjected to excessive heat.
Figure 1 Remove Center
Figure 2 Melt Solder
Figure 3 Lift Socket
7711A
Rework of
Electronic Assemblies
Revision:
Date: 2/98
PLCC Socket Removal
Hot Air Pencil Method
Number: 3.10.4
Product Class:
Skill Level: Advanced
Level of Conformance: Medium
Material in this manual, IPC-7711 Rework of Electronic Assemblies, was voluntarily established by Technical Committees of
IPC. This material is advisory only and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the
use, application, or adaptation of this material. Users are also wholly responsible for protecting themselves against all claims
or liabilities for patent infringement. Equipment referenced is for the convenience of the user and does not imply endorsement
by IPC.
Page1of2
Copyright Association Connecting Electronics Industries
Provided by IHS under license with IPC
Not for Resale
No reproduction or networking permitted without license from IHS
--``,``,-`-`,,`,,`,`,,`---
NOTES
IPC-7711A
Number: 3.10.4
Revision:
Date: 2/98
Subject: PLCC Socket Removal
Page2of2
Copyright Association Connecting Electronics Industries
Provided by IHS under license with IPC
Not for Resale
No reproduction or networking permitted without license from IHS
--``,``,-`-`,,`,,`,`,,`---
EQUIPMENT REQUIRED
Continuous vacuum desoldering system
Desoldering tip
MATERIALS
Flux
Cleaner
Tissue/wipes
PROCEDURE
1. Remove conformal coating (if any) and clean work area of any contamination,
oxides, residues or fluxes.
2. Install desoldering tip into handpiece.
3. Start with tip temperature of approximately 315°C and change as necessary.
4. Apply flux to all land areas. (See Figure 1.)
5. Lower tip contacting end of land(s) with tip. (See Figure 2.)
6. Confirm solder melt of contacted land(s), apply vacuum and sweep tip over land
holding tip in contact with solder to extract excess solder from PWB land(s).
(See Figure 3.)
7. Lift tip at end of last row, hold vacuum to clear all molten solder from the heater
chamber. (See Figure 4.)
8. Repeat for all lands.
9. Return handpiece to its stand.
10. Clean lands as required for component replacement.
NOTE
The individual method is the method of choice for fine pitch land patterns.
Figure 1 Flux Lands
Figure 2 Position Tip
Figure 3 Melt Solder & Apply Vacuum
Figure 4 Lift Handpiece
7711A
Rework of
Electronic Assemblies
Revision:
Date: 2/98
Surface Mount Land Preparation
Individual Method
Number: 4.1.1
Product Class: R, F, W, C
Skill Level: Intermediate
Level of Conformance: High
Material in this manual, IPC-7711 Rework of Electronic Assemblies, was voluntarily established by Technical Committees of
IPC. This material is advisory only and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the
use, application, or adaptation of this material. Users are also wholly responsible for protecting themselves against all claims
or liabilities for patent infringement. Equipment referenced is for the convenience of the user and does not imply endorsement
by IPC.
Page1of2
Copyright Association Connecting Electronics Industries
Provided by IHS under license with IPC
Not for Resale
No reproduction or networking permitted without license from IHS
--``,``,-`-`,,`,,`,`,,`---