The gripper is the most frequently asked question in non-standard automation design. Get it wrong and the whole pick-and-place cell needs rework; get it right and the cell runs for years without drama. This guide walks through five practical checks we apply before recommending a gripper to any client.
1. Payload and safety factor. Add the workpiece weight to the weight of any tooling mounted on the jaws, then apply a safety factor of at least 1.5x for horizontal gripping and 2x for vertical gripping. Pneumatic grippers lose holding force as air pressure drops, so design against the worst case, not the catalogue value.
2. Stroke and part geometry. Decide whether you grip internally or externally, then check finger stroke against the part's tolerance range and surface shape. For round parts, a three-jaw or V-jaw gripper centres the workpiece automatically; for thin plates, use long parallel jaws to spread the clamping force.
3. Environment and materials. Check temperature, dust, washdown or cutting-fluid exposure before choosing body material and sealing. Standard aluminium bodies are fine for most assembly cells; food and chemical lines usually need 304 stainless or coated bodies with IP-rated seals.
4. Integration and sensors. Confirm mounting pattern, air ports, and sensor options early. Most builds need position feedback: magnetic switches on the body or proximity sensors near the jaws. If the cell uses tool changing, keep the gripper footprint and port positions within the tool-changer envelope.
5. Spares and service. Prefer models with replaceable jaw blanks and common seal kits. When a line goes down, a 24-hour spare part matters more than the initial purchase price.
If you are unsure where to start, a proven pneumatic three-jaw design with replaceable jaws covers most assembly applications. Request a free sample from our library and test it in your own fixture before committing to a full purchase.