Accurate length measurement of straight seam steel pipes is essential during manufacturing and quality control. Due to large pipe sizes and complex production environments, various measurement methods are applied in practice, each with its own working principle, accuracy level, and limitations.
1. Measuring Straight Seam Steel Pipes Using a Grating Ruler
Working Principle
Two fixed-length grating rulers are installed at both ends of the straight seam steel pipe. A rodless cylinder moves the grating rulers toward the pipe ends. The pipe length is determined based on the optical interference signals generated by the grating rulers.
Characteristics
High measurement accuracy
High equipment cost
Complex maintenance requirements
Sensitive to dust, vibration, and harsh site conditions
2. Measuring Straight Seam Steel Pipes Using a Camera System
Working Principle
This method relies on image processing technology. Photoelectric switches are installed at equal intervals along a section of the roller conveyor. A camera and light source are installed above another section. When the steel pipe passes through, its length is calculated based on the image position captured by the camera relative to the triggered photoelectric switch.
Advantages and Limitations
Enables real-time, online length measurement
No interruption to production flow
Susceptible to external light interference
Strong light reflection at chamfered pipe ends may cause reading errors
3. Measuring Straight Seam Steel Pipes Using an Encoder
Working Principle
An encoder is installed on a hydraulic cylinder that pushes the steel pipe along the roller conveyor. Photoelectric switches are arranged at equal intervals. When the pipe end triggers a switch, the encoder reading is used to calculate the cylinder stroke, which determines the pipe length.
Advantages and Limitations
Simple measurement principle
Requires the pipe to be lifted during measurement
Photoelectric switch detection may introduce errors
Additional verification may be required for higher accuracy
4. Length Measurement Using an Improved Encoder System
Working Principle
This indirect measurement method determines pipe length by measuring the distances between both pipe end faces and their reference points. Measuring carriages are positioned at each end of the pipe with an initial spacing of L. The carriages move toward the pipe ends by distances L₂and L₃, respectively. The pipe length is calculated as L−L₂ −L₃.
Engineering Advantages
Suitable for large-diameter straight seam steel pipes
Adaptable to complex production environments
Avoids interference from lower support frames
Easy operation
Measurement accuracy within±10 mm
Repeatability≤5 mm
United Steel Industry As the most important steel pipe manufacturer and exporter in China, in the past 20 years, we have completed more than 100 projects, with partners in more than 100 countries, and established relationships with oil and gas and EPC companies in many countries business relationship.
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please consult:Email:Sales@usisteels.com
