Do you struggle with the one or more of your pneumatically operated gates opening or closing too fast? It can be frustrating to want to add only a small amount of cement, but a a jog of the gate causes way more than you may want. Whether using a fully automatic or manual control system for your concrete plant, this is problem that can frequently be solved with the addition of a simple flow control valve on the air exit port on the function you would like to slow. Most concrete batch plants use pneumatic systems or air systems to open and close its gates. These air systems normally employ solenoid valves to control the input and sometimes the exit of air from the cylinders or valves they are controlling.
Hopefully you aren’t feeling too overwhelmed already because it is quite simple in concept. Different manufacturers of plants will use different types of valves and methods of plumbing, but if you understand the concept then you should be equipped to better identify the specific steps necessary to control your gates. The solenoid valve receives signal form either a manual or automatic control system so it knows when to open or close. Some valves can be setup as “inching” meaning they can be all or partially opened, but often these valves are setup to be open or closed. Imagine the system stress and mess you may have if the water in your kitchen was either on max or off. You may be asking yourself, why wouldn’t you just use inching valves everywhere, but that is a complicated answer we will address in another post.
As mentioned the good news is even if you have the simple on/off solenoid valves you can still slow them down in one or both directions. The air that goes into the cylinder or valve to open or close it must also exit the system. By adding a valve to the air exit and slowing the exit of air you are slowing the overall operation of the device. Where does the air exit you may be asking? That depends on the specific design of the plant. The air may be returned to the solenoid and relieved or it is possible that it could exit at the end of the cylinder or valve. You will need to carefully inspect your plant design or consult with its manufacturer for this information. It is important to remember if you are inspecting your plant to be properly safety trained in lock out / tag out and all other applicable safety programs. Injury or death can occur during the operation of a concrete plant.