TPT January 2013

Inspection, measuring and

testing

Box end hydrostatic test station ENVIRONMENTAL concerns place stringent requirements on any piece of pipe that will be carrying oil products either under the ground or under the ocean: it simply must not leak. To ensure the integrity of OCTG, a manufacturer must vet each piece of pipe using a hydrostatic pipe tester or hydrotester. The testing process is simple: the pipe is capped at both ends and completely filled with water. The water inside the pipe is pressurised to a specified high pressure to see if any leaks occur. of pipe with coupling; in contrast the Brandt box end hydrostatic pipe tester may only require 4 litres. The Brandt tester

In the Brandt box end method, the pipe is initially positioned against an adjustable stop. A Swedish lever or rotary arms transfer device pick up this pipe and place it onto a series of V-rolls that are already at the pre-set height to match the hydrotester test head’s centreline. The V-rolls then convey the pipe forwards to the pinch-clamp, which contains linear bearings, driven V-rolls, an encoder and a timing device that self-centres and drives the pipe into the hydrostatic tester tooling accurately. The lower pipe saddles rise to support the bottom of the pipe within the hydrotesting station. At the same time, an upper clamp secures the coupling to prevent the pipe from moving during the test. The test head engages the pipe, and a collapsible type urethane seal in the interior of the pipe expands, whilst the external seal is pressurised to seal onto the outside diameter of the coupling. This cavity is filled with water while the purge valve is open, allowing trapped air from inside the pipe and coupling to escape. Once the cavity is filled with water, the water-over-oil hydraulic pressure intensifier is activated, bringing the internal pressure up to a specified test set point. Leaks are monitored visually using high-resolution industrial cameras directed at the joint, and also electronically with the PLC monitoring both the test pressure and the intensifier position. Pipes that do not require testing can be conveyed through the machine without being engaged by the tester. The Brandt box end hydrostatic pipe tester can operate in fully automatic, geometry can be performed with the high precision optical geometry measuring system “Geometry-Control- System” GKS. At first glance the operator notices if the dimensions of the work-piece are still within the given tolerances, so that he can quickly respond to the deviation by re-adjusting the manufacturing process or by stopping it. By doing so, it is assured that the given tolerances are maintained,

Typically, once a piece of pipe has passed that test, it moves downstream on the finishing floor, where it is threaded and then a coupling is attached. Some customers need to test the pipe again at that point, either due to local regulations or to meet their own standards or standards of the regulatory body such as API or GOST. This has ordinarily been done by placing the entire pipe in the hydrotester for a second time. However, a quicker and more effective solution is to conduct a pressure test on only those items that have been added to the pipe, namely the threads and the coupling. The Brandt box end hydrostatic pipe tester seals both the inside of the pipe and outside diameter of the coupling to prevent leakage. The coupling is filled with water, which is then pressurised up to, for example, 20,000 psi depending on material grade specifications. The PLC controlled computerised sensors and high-resolution cameras monitor for leaks and weak spots in the joint. Testing just the threads and couplings not only provides faster cycle times than testing a full length of pipe, it also uses far less water and associated additives. A full-pipe hydrotester may need more than 1,500 litres of water to test a length THE precise manufacturing of single components is crucial for the optimal functioning of a system. Even a hundredth of a millimetre counts, and the smallest deviations must be quickly recognised and corrected. Monitoring the manufacturing processes by means of the latest measuring systems represents a key issue for quality assurance. The measurement of components’

semi-automatic and manual modes. All adjustments, from test pressure to fill pressure to test time, can be controlled at the touch of a button from the operator’s HMI station, where alarm diagnostics and maintenance screens provide accurate trouble-shooting. The tester can be completely integrated into higher level computer networks, making test data from each pipe available to other areas of the finish floor, including the drifting station, marking system or bundler. Typical data collected includes pipe grade, outside diameter and length, lot number, test pressure, actual test times, and test results.

Brandt Engineered Products Ltd – Canada Email: engineeredproducts@brandt.ca Website: www.brandt.ca High precision geometry control

scrap is avoided and the process of manufacturing is optimised. The measuring principle is always the same: depending on the work-piece size, the measuring system can be mounted with up to four cameras. MSGMaschinenbau GmbH – Germany Fax: +49 2972 9774019 Email: kontakt@msg-maschinenbau.de Website: www.msg-maschinenbau.de

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J anuary 2013