Is the magnetic valve of the surface mount motor broken? The judgment methods and replacement tutorials are all here

One of the most frustrating problems with the surface mount technology (SMT) machine is the malfunction of the pneumatic system. It won't stick, won't stick firmly, and the movement is laggy... Is your first reaction to suspect the vacuum pump, the pipeline, or even the mounting head? But very often, the "culprit" is actually an insignificant little thing - the solenoid valve.

Despite its small size, this thing is responsible for switching gas paths, controlling adsorption, blowing air, pushing materials and various other key actions. When it breaks down, the problems are all kinds of strange and not easy to spot at a glance. So this article will tell you: how to determine if the solenoid valve is broken and how to replace it quickly and stably after it is broken.

The solenoid valve is not working. It is highly unlikely to report an error directly, but you will notice the abnormality from the movement of the patch. Several common manifestations are as follows:

• 1. The suction nozzle doesn't suck or the suction force fluctuates
  At this point, the vacuum pump might be in good condition, but the solenoid valve failed to switch, resulting in the vacuum not being correctly guided to the suction nozzle.
• 2. Delayed and incoherent movements during mounting
  For instance, if a piece is picked up but not placed, or placed in the wrong position, the reason is often that the solenoid valve does not respond in time or gets stuck.
• 3. Even though I heard a "tap-tap" sound, my anger didn't subside
  You might think the valve is functioning properly, but in fact, it's just that the coil is energized, while the valve core doesn't move or gets stuck.
• 4. A certain workstation frequently drops parts, while everything else is normal
  This indicates that it is not a systemic issue but rather that the solenoid valves in individual gas lines have failed or are half-dead.

If you suspect that there is a problem with the solenoid valve, the following steps of troubleshooting methods can help you quickly locate it

1. Listen to the sound
   After being powered on, the solenoid valve should make a slight "click" sound. If there is no sound, it might be that the coil is burned out. If there is a sound but the operation is abnormal, it may be that the valve core is stuck.
2. Manual trigger test (strongly recommended)
   In the engineering mode or manual maintenance interface, trigger a certain solenoid valve separately to see if the action is in place. If it can be triggered but there is no pneumatic response, it is most likely that the valve body is broken.
3. Remove the air pipe to observe the airflow
   Unplug the hose connected to the air outlet of the solenoid valve and check if there is any air flow when it is triggered. No air? Then there is a 100% problem.
4. Measure the resistance value of the coil with a multimeter
   The normal resistance value is generally between 10 and 30Ω (depending on the brand). If it is an open circuit or 0Ω, it indicates that the coil has burned out.

Replacing an electromagnetic valve is not complicated at all. As long as you are not afraid to take action and follow the steps below, there won't be any problems.

1. Step 1: Cut off the power and release the air
   Remember to cut off the power and gas supply! This is the basic operation. Turn on the main air source of the machine to exhaust air and confirm that there is no residual air pressure.
2. Step 2: Take photos to record the positions of the conduits and plugs
   Solenoid valves usually have multiple pipelines and cable joints. Don't trust your good memory. Taking photos is the most reliable way. Some models have several valves on one plate, and if the numbers are not clear, it is easy to install them incorrectly.
3. Step 3: Remove the old valve
   When disassembling the cable, be careful not to pull it hard. Some joints have locks. The pipe joints should be pressed first and then pulled to prevent violent damage.
4. Step 4: Replace the valve with a new one and reinstall it as per the original diagram
   Connect the wires according to the diagram. Do not connect the positive or negative terminals. Insert the pipe to the bottom and check if it is loose or leaking.
5. Step 5: Power-on and ventilation test
   Turn on the main gas source and power supply. Check one by one whether the actions are normal through manual testing. Check for any issues such as air leakage, response delay, or adsorption failure.

There are numerous brands of solenoid valves on the market, but the solenoid valves used in surface mount technology (SMT) machines have requirements for response speed, lifespan, and sealing performance. Buying them randomly is unreliable.

Note a few points

• Model matching is the most important:
  It's not the case that just because they look the same, they can be used interchangeably; even if the parameters are slightly different, they may not match.
• Don't just seek cheapness:
  The service life of cheap aftermarket solenoid valves is short, and it's common for them to get stuck within two months.
• When choosing a brand, give priority to original or certified parts:
  for instance, custom valves from SMC, FESTO, and Hanwha, which have stable performance.
• If you are using a third-party Feida or modified equipment, it is also recommended to test a batch before purchasing in large quantities.

Rather than waiting for it to break down and then panic, it's better to establish a maintenance plan on a regular basis:

Although the surface mount electromechanical solenoid valve is small, once it malfunctions, the impact can be a chain reaction. Only by making accurate judgments and quick changes can the entire line not be dragged down by "small components". It is much more convenient to pay more attention to its movements and sounds in daily life and do some small maintenance in advance than to repair it later.