How to Measure Gas Springs: A Comprehensive Guide
Gas springs, also known as gas struts or gas dampers, are crucial components in various applications, from car trunks and truck tailgates to medical equipment and industrial machinery. Knowing how to accurately measure them is essential for replacement, repair, and design purposes. This guide will walk you through the key measurements needed and how to take them effectively. Understanding these measurements ensures you get the correct replacement and prevents potential safety hazards or malfunctions.
What Measurements Do I Need to Take?
There are several key measurements required to correctly identify a gas spring. Don't worry; it's simpler than it sounds! These include:
- Extended Length: This is the total length of the gas spring when fully extended. Measure from the center of the mounting eyelet at one end to the center of the mounting eyelet at the other.
- Compressed Length: This is the total length of the gas spring when fully compressed. Again, measure from center eyelet to center eyelet.
- Stroke Length: This is the difference between the extended length and the compressed length. It represents the distance the gas spring travels during its operation. (Extended Length - Compressed Length = Stroke Length)
- Diameter (Body Diameter): This refers to the diameter of the gas spring's cylindrical body. Measure the body's widest point, excluding any mounting hardware.
- Mounting Eyelet Diameter & Type: This includes the diameter of the mounting eyelets at both ends of the gas spring and the type of attachment, such as a ball stud, clevis pin, or threaded stud. Carefully note if the eyelets are the same or different.
- Force (Newtons): This specifies the force the gas spring exerts at a specific point in its stroke. Often, this is specified as the force at the fully extended position, but it can vary along the stroke length. This is critical for ensuring the replacement spring offers the correct level of support. You'll typically find this information on a label or stamped on the existing gas spring itself.
How to Measure Gas Springs Accurately
Here's a step-by-step guide for accurate measurements:
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Safety First: Before you begin, ensure the gas spring is safely secured or supported to prevent injury. Gas springs can exert considerable force and can cause harm if handled incorrectly.
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Extended Length Measurement: Carefully extend the gas spring completely. Using a measuring tape or ruler, measure the distance between the centers of the mounting eyelets at both ends. Record this measurement precisely.
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Compressed Length Measurement: Carefully compress the gas spring completely. Measure the distance between the centers of the mounting eyelets as before. Record this measurement.
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Stroke Length Calculation: Subtract the compressed length from the extended length to determine the stroke length.
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Diameter Measurement: Use a caliper or measuring tape to measure the diameter of the gas spring's cylindrical body.
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Mounting Eyelet Measurement & Type: Carefully measure the diameter of each mounting eyelet and note the type of attachment. Draw a sketch if it helps to document the type of eyelet and its orientation.
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Force Measurement: Check for a label or marking on the existing spring that indicates the force rating in Newtons (N). If this information isn't available, you may need to consult the manufacturer's specifications or documentation related to the original equipment.
Where to Find the Force Rating if it's Not on the Spring?
Finding the force rating without direct labeling can be challenging, but some methods include:
- Check Original Equipment Manufacturer (OEM) documentation: If you know the manufacturer and model of the equipment that uses the gas spring, searching online for manuals or parts lists could provide the correct force specification.
- Contact the gas spring supplier: If you know the brand and/or part number of the gas spring, contacting the supplier may be your best bet. They can provide the necessary details.
What if I Can't Find All the Measurements?
If you can't find all the specifications on the existing spring, providing as many measurements as possible to a supplier will allow them to find a suitable replacement. However, having a complete set of measurements is crucial for precise replacement.
By following these steps, you can accurately measure your gas springs, ensuring you obtain the correct replacement part and maintain the safety and functionality of your equipment. Remember safety is paramount throughout the process.
