Desoldering

A desoldering pump designed to remove liquefied solder ( solder ) when solving a solder joint.

Manually operated Guns

When an electric or electronic component is soldered by more than a single solder joint to a circuit board, would have to remove all of the component solder joints are melted simultaneously. This is in general - also to protect the device - not possible, which is why the tin must be successively removed from all solder joints. The liquid solder can be absorbed either in the simpler case with a solder wick or a desoldering pump.

A desoldering pump has a heat resistant plastic tip, for example, Teflon, where the liquid solder will not stick. In the pump, a negative pressure is created which sucks in the air and the liquid solder. A peak with a small opening would allow more precise operation and a longer suction, but the free diameter of the tip must have a sufficiently large diameter to allow for a tin in the top not grown cold and clogs them. On the other hand, the diameter must enable a sufficiently powerful air stream which is able to ' entrain ' the liquid tin.

Simple manual Guns generally consist of a cylinder and a piston which is biased by a coil spring. By pressing a button, the spring is triggered and the receding piston creates a region strong vacuum, into which the air flows in from the outside. Slightly higher pumps of this type have a mechanism that compensates for the recoil occurring. Thus, the tip does not hit on the solder joint.

Electrically operated desoldering

In professional fields, there are electric desoldering pumps, which have an electrically heated desoldering tip and a vacuum system. These devices are either connected to a central vacuum supply, or to generate the negative pressure with a motor-driven vacuum pump. Furthermore, there are systems which are connected to compressed air and generate the required sub ​​pressure for an integrated Venturi nozzle. The desoldering nozzle is made of a metal material. It transmits the heat to melt the solder in the solder joint. This is to ensure that the transfer surface of the solder desoldering nozzle for better heat transfer takes good. The aspiration of the liquid solder is usually triggered by a button on the hand desoldering or by footswitch.

Cleaning of Entlötgeräten

The absorbed Lot is accumulated with manual pumps in the working chamber of the cylinder and usually discharged by re- tensioning the desoldering pump again. After extended use, the solder residue must be removed from the opened device. In heated industrial Entlötgeräten there are usually downstream of the nozzle a Lotgefäß ( for example in the form of a glass tube ) in which the liquid solder is drawn and cooled there. At regular intervals, the solder must be removed and the desoldering be cleaned.