The overflow valve located on the upper part of the machine. When the machine does not work properly, we need to clean the overflow valve or the valve below. So how to clean the relief valve? When the machine tool is stepped on the footswitch, the valve light is already on, but the tool holder does not go down and the cutting action is not completed, which indicates that the oil circuit is the problem, then we need to clean the valve.
To clean this valve, first find a 4mm wrench, because these are 5mm hex screws. First, remove the upper layer, remove the four screws in turn, and then pay attention to the O-ring. If it is stuck below, you need to install it. Make sure that the seal is completely installed on it. Then remove the second layer, or four screws, and remove them in turn. You will see a spring after you take it down. You need to pay attention to this O-ring. If it is stuck below, you must install it. The oil will leak here. Let's put the two layers removed first, and there is a spool in the hole as shown in the figure. Under what circumstances does this spool need to be removed? When the machine cannot work normally and cannot generate pressure. Why is there no pressure? It is because this valve core is stuck by foreign objects or metal scraps inside. At this time, take out the spool to observe it, first see if there is any problem around the spool, and then see if there is metal scrap or foreign matter stuck in this hole so that the spool cannot work normally. Then we reach in with our hands and gently look for any foreign objects. If there are foreign objects, our hands will have a noticeable feeling.
Then find a magnetic screwdriver, put the screwdriver in and look for it. If metal scraps are attracted to the screwdriver and brought out. After making sure there is no problem in this hole, make sure that the valve core is OK. Move the spool back and forth to see if the spool can work properly. After the valve core is installed, install the spring. Some springs have a small gland on it. If there is a small gland, it must be installed on the upper end of the spring. Because this spring of our shears has the same ends, it does not need to be installed. When installing the second-layer valve, pay attention to ensure that the O-ring is complete, and tighten the valve diagonally after installing it. When installing the first layer of the valve, pay attention to whether there is any problem with the O-ring and tighten it diagonally. When the machine cannot generate normal working pressure, the overflow valve needs to be cleaned. When the pressure is abnormal or no pressure, although the valve light is on, no pressure is generated, the valve needs to be cleaned.