Wave soldering and reflow soldering are two of the more common way, here we talk about the difference between reflow and wave soldering.
   SMD. Surface mount technology, referred to as SMT, as a new generation of electronic assembly technology has penetrated into all fields, SMT product has a compact structure, small size, resistance to vibration, impact, high-frequency characteristics, high production efficiency. SMT circuit board mounted in the linking process has occupied a leading position.
   A typical surface mount process is divided into three steps: applying solder paste reflow ----- ---- mount components
   The first step: applying solder paste
   The aim is an appropriate amount of solder paste is applied in a uniform pad on the PCB, and the PCB to ensure that the chip components corresponding to the pads during reflow soldering, to achieve a good electrical connection and have sufficient mechanical strength.
   Solder paste is a mixture of alloy powder, paste and solder paste made some additives having a certain viscosity characteristics and excellent touch it. At room temperature, because the paste has a certain viscosity, electronic components can be attached to the PCB pads, the tilt angle is not too large, there is no external circumstances can impact the general elements will not move when welding when the paste is heated to a certain temperature, the molten alloy powder in the solder paste reflow, solder wetting liquid components of the welding ends PCB pad, and the pad was cooled welding ends with solder components interconnected together to form an electrical and mechanical with solder connection.
   Solder paste is applied by a special device on the pad, its equipment:    Automatic printing presses, semi-automatic presses, manual printing, semi-automatic paste dispenser or the like.
   The method is applied to the application of the advantages and disadvantages
   Machine printing larger quantities, delivery time is tight, adequate funding for mass production, high production efficiency using the process is complicated and larger investment
   Manual printing small batch production, product development and easy operation, low cost of doing so need to manually locate and can not be mass-produced
   Manual dispensing general board of the development, repair solder pads without the aid of equipment, research and development to production applies only to pad pitch of 0.6mm or more in dispensing element
   Step two: mount components
   This step is the placement machine or manually mount chip components to accurately printed solder paste or adhesive patch PCB surface corresponding position.