Four methods of measuring the length of SSAW steel pipe

Measuring the length of SSAW (Spiral Submerged Arc Welded) steel pipes is a critical step in the manufacturing process, ensuring that the final product meets specification and is ready for use. There are several methods available for accurately measuring the length of SSAW steel pipes, each with its advantages and applications. Below are four commonly used techniques:

1. Improved Encoder Length Measurement

This is an indirect measurement method that determines the length of the SSAW steel pipe by measuring the distance between the two ends of the pipe. The process begins by setting up a length measuring trolley at each end of the pipe, with the initial position set to zero. As the pipe moves along, the trolley travels a distance, denoted as L2 and L3 at both ends. The final length of the SSAW steel pipe is calculated as L - L2 - L3. This method is easy to operate and delivers a measurement accuracy within±10mm, with a repeatability of≤5mm.

2. Grating Ruler Length Measurement

In this method, two fixed-length grating scales are installed on the outer sides of the two ends of the SSAW steel pipe. A rodless cylinder drives the grating scales toward the ends of the steel pipe. The light interference effect between the scales is then used to accurately measure the length of the pipe. This method provides precise measurements, relying on optical principles for accuracy.

3. Camera-Based Length Measurement

This method uses image processing technology to determine the length of SSAW steel pipes. A series of photoelectric switches are positioned at equal intervals along the steel pipe's conveying roller table, while a light source and camera are set up at another section. As the steel pipe passes through the area, the camera captures the position of the photoelectric switch on the screen, allowing the length of the pipe to be calculated based on the position of the switch. This method is efficient and can be automated for continuous monitoring.

4. Encoder Length Measurement

In this approach, an encoder is installed within the oil cylinder used to push the SSAW steel pipe along the roller table. A series of photoelectric switches are placed at equal intervals along the path of the pipe. As the pipe moves forward, it activates the photoelectric switches, and the encoder’s reading is recorded. The movement of the oil cylinder is tracked, and the stroke of the cylinder is used to calculate the length of the steel pipe. This method offers precise and automated length measurement.

These four methods—each with its specific application and benefits—ensure the accurate measurement of SSAW steel pipes, allowing manufacturers to produce pipes that meet the required length specifications and quality standards.