Three Types of AC Linear Solenoids and Their Basic Properties: Laminated, C-Frame and D-Frame

There is a large range of AC solenoids available from industrial equipment manufacturers, suitable for use in a wide range of different applications. Each solenoid is designed with a set of specific properties, and may be used in more than one application. While standard solenoids are readily available, custom built solenoids are also an option if a certain set of non-standard properties are sought after.

When an electric current is applied to an electromagnetic solenoid, the resultant magnetic field drives a metallic slug or armature in the centre, pushing or pulling it to create mechanical action. This mechanical energy can then be used to drive various devices such as switches, latches, starters or valves. Whilst individual solenoid designs differ in the way the mechanical energy is dispersed, all electrical solenoids work on this same principle, allowing any particular solenoid to be utilised in a wider range of applications and devices.

One of the basic properties of AC solenoids is an initially high stroke force as the current rushes in; for this reason, they can use longer strokes compared to DC solenoids. Some common types of AC solenoids available are linear type solenoids, including ac laminated solenoids, C-Frame solenoids (u frame solenoids) and D-Frame solenoids. Linear solenoids generate mechanical force in a straight line.

  • AC laminated solenoids are produced using a special method that uses several thin sheets, known as laminations. Each lamination is separately insulated, and then are collected together to form a 'stack', or the housing and yoke. This unique design allows the closing times of AC laminated solenoids to be very short (typically less than 16 milliseconds) while their initial attracting forces are very high, giving them the unique ability to hold a heavy load while operating with minimal noise.
  • C-frame or U-frame solenoids are linear solenoids that are shaped like the letter 'C' or 'U'. In C-frame solenoids, the magnetic field only flows through one side. These solenoids are the most basic type of linear solenoid in terms of design, and are generally also the smallest type available. 
  • D-frame solenoids are also linear solenoids that are shaped like the letter 'D', surrounding the coil like a frame. The higher quality D-frame solenoids can be identified by a single-unit frame with rounded corners that forms a closed shape around the coil. In D-frame solenoids, the magnetic field flows through two of the four sides. D-frame solenoids offer a balance between their cost, performance and size.