Ergonomic considerations when choosing a Torque Screwdriver
There are serval key ergonomic considerations when choosing a torque screwdriver. Using the wrong screwdriver can cause more than just an aching wrist. As well as the health impacts, productivity and quality will almost certainly suffer. This is avoidable by taking the time to understand what to look for in a torque screwdriver. Here’s what to know.
Screwdriver Jobs Vary
Start by reviewing these aspects of the task:
Screw orientation – horizontal or vertical?
Reaction torque – larger diameter fasteners will be tightened to a higher torque. That creates more twisting force on the operator’s wrist.
Axial force – does the operator need to lean in or otherwise push the fastener as it’s turned?
Mobility – will the tool be used only in one place or will the operator need to move it around?
Choices in Ergonomic Torque Screwdrivers
Torque screwdrivers are produced in in-line, pistol grip and angle head form factors. Each has characteristics that makes it right for some jobs and wrong for others.
In-line Torque Screwdrivers
An in-line torque screwdriver is gripped around the cylindrical body. That makes it a good choice in light assembly where it can be suspended over the workbench. The operator just grasps the body and pulls it down.
Two limitations are: the operator can’t apply a lot of axial (downwards) force, and the tool will generate considerable reaction torque. This style is best used with smaller fasteners inserted vertically and where tightening torque is low. (An upper limit is 44 inch-pounds.)
Pistol Grip Torque Screwdrivers
The pistol grip puts the wrist in a comfortable position when the tool is held horizontally. It also lets the operator apply axial forces. However, using it vertically downwards may require twisting wrist and forearm into an awkward position.
Offsetting the hand from the rotation axis helps resist reaction torque. For this reason a pistol grip torque screwdriver is often preferred with larger diameter fasteners.
Angle Head Torque Screwdrivers
These put the rotation through 90⁰ from the hand grip. It means less space is needed above the fastener but limits how much vertical force the operator can apply.
Other ergonomic considerations when choosing a Torque Screwdriver:
Grip diameter — above 1¾” diameter an in-line torque screwdriver becomes uncomfortable to hold. Female workers may prefer one that’s smaller. For precision work a smaller diameter screwdriver can be held in a finger-and-thumb pincer grip.
Reaction torque — minimize the impact on the operator by using torque reaction bars.
Tool weight — lighter is generally better. Whenever possible, suspend the tool from a spring balance.
Noise and vibration — prolonged exposure to loud noise can cause hearing damage so look for the quietest tool possible. Avoid the vibration of slip-clutch tools by choosing those with auto shut-off clutches.
Battery or hose/cable — battery-powered tools are heavy but easier to move. Tools with air hoses or power cables are lighter, especially if suspended from a balance.
Get the Right Tool
The right screwdriver minimizes operator fatigue. That boosts productivity and lessens the chance of mistakes. For more advice on ergonomic torque screwdrivers call Express Assembly at 1-866-864-2303 or Contact Us.