Selecting a Preset or Adjustable Torque Screwdriver
There are a variety of "Preset" and "Adjustable" torque screwdrivers, but selecting the correct hand screwdriver for you application depends on your objective. Preset torque screwdrivers offer tamper-proof operation, while adjustable screwdrivers offer different setting options for applications that require more than one torque value.
A preset torque screwdriver is similar to a person setting an alarm clock to signal the achievement of a selected time. The torque screwdriver is pre-set to the required torque value of the application and then the tool signals the operator when torque is achieved. A preset torque screwdriver does not feature an external adjustment scale. These tools have internal adjustment mechanism for setting the torque value and must be preset using a torque tester. The preset screwdrivers are ideal for production applications where there is one torque setting required and you need to prevent incidental or operator tampering of the torque setting. However, if the torque specification changes or new project requires a different torque setting, the preset torque screwdriver is still flexible enough that a new torque setting can be set internally using a torque analyzer.
Adjustable torque screwdrivers offer different setting options for applications that require more than one torque value. The adjustable screwdriver does feature an external adjustment scale, which allows for an operator to adjust the torque setting as needed for the application. A quality adjustable screwdriver typically features a ring or bezel device that allows an operator to press down to adjust the torque setting and then locks into place once released preventing incidental torque adjustment. These tools are ideal for field service or production applications as the adjustable torque screwdriver provides manufacturers with flexibility.
The cam-over philosophy of each Mountz hand torque screwdriver prevents a fastener or bolt from being over-torqued. Whether using a preset or adjustable tool, the design action of the Mountz torque screwdrivers is such that when the tool reaches its set torque value the mechanism disengages from the drive thus limiting the torque applied. Inside the screwdriver, a precision radial ball clutch "slips-free" when the set torque is reached preventing over-torquing. Also, the thrust bearings insure that the torque setting is independent of any end load applied by the operator. Mountz offers the most complete array of torque screwdrivers available on the market today.
Mountz torque screwdrivers are known to be reliable, accurate and meet or exceed the principal requirements of International Standard ISO 6789:2003.
Controlling torque is essential for companies to ensure their product's quality, safety and reliability isn't compromised. The failure of a three-cent fastener that isn't properly tightened can lead to catastrophic or latent failures. Fasteners that are insufficiently fastened can vibrate loose and excessive torque can strip threaded fasteners. The cam-over philosophy of each Mountz torque screwdriver prevents operators from influencing the torque output when tightening fasteners.