TPT July 2019

MEA SUR I NG & MARK I NG

Pipe and tube marking and measuring THERE are many different needs for marking and measuring pipes and tubes for the OCTG industry; these needs continue to grow as API, customer and internal requirements become more demanding for proper identification, tracking and improved quality. Measurements include both length and weight, followed with associated tolerance checks and calculations to meet various API or customer driven re- quirements. Length measuring methods include lasers, ‘photo-eyes’, proximity sensors and encoders. Accurate weight measurement can be performed via lift-and-weigh devices, cross-transfer equipment or even roll-by methods by installing the load cells beneath the sup- port structure.

The actual specific marking process- es can be performed in a number of automatic or manual methods, includ- ing: stencilling, stamping, application of labels/tags and line/band spraying. OD and ID stencilling can be used on just one end of the pipe, both ends or even full-length, and can be achieved with in-line, cross transfer or overhead beam equipment. Variations of the above methods and requirements can often be combined into a single integrated machine, commonly referred to as weigh measure stencil (WMS) equipment, that utilises a multi-station cross transfer machine to process multiple pipes at once. For example, the first station can process weigh and length measure functions, the second station can stamp, and the third station can stencil. Equipment can include cross-transfer walking beams to move the pipe from station to station, or robots may be better suited for the variability of pipe dimensions associated with both ID and OD marking needs of stationary pipes. Individual requirements along with ingenuity and technology will drive the specific solution.

Fortunately, the various technologies implemented to meet these changing needs also continue to evolve and can be used to reduce initial investment as well as down-time and maintenance costs. Specifically, advancements in lasers, robotics, sensors, machinery and automated stencil equipment, as well as barcode marking and reading can improve accuracy and simplify implementation. To save on equipment cost, in- line equipment can be used. Length measurement and stencil marking are easily accomplished ‘on the fly’, while weight can be measured on approaching roll-by gravity transfer rails. Alternatively, if conveyer space is limited and/or cycle time is critical, then cross-transfer equipment can be implemented to perform various functions simultaneously in a small footprint. The equipment is first used to mea- sure the pipe and then perform tolerance checks, followed by marking as needed and then finally reporting the information on a per-pipe or per-order basis.

The measurements are then used to validate, and report each specific pipe by performing weight-to-length calcula- tions and comparing those to the API acceptable tolerances. Once the specific pipe measurement information is gathered and combined with the remaining message that has been downloaded from the host, the markings can be applied to a range of locations via a range of methods. The two most common methods are OD stencil and/or OD stamp marking of man-readable text and/or logos, followed by the need for OD colour bands. Additionally, barcodes (either 1D or 2D) can be utilised, not just to meet customer or end-user requirements, but also for the manufacturer’s own internal tracking and traceability needs. Beyond that, interest in defect marking and thread engagement verification ( 3 / 8 " triangle) is also growing.

InfoSight Corp – USA Fax: +1 740 642 5001 Email: sales@infosight.com Website: www.infosight.com

An example of pipelines used in the OCTG industry

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JULY 2019