The United Metallurgical Company (AO OMK) is in the process of upgrading all the existing OMK facilities that manufacture electrically welded OCTG tubulars and improving the product offering, as well as the quality of the oil and gas production pipe. It is also commissioning facilities to make products OMK has never made before, such as oil production tubing.
When the mill was commissioned in 1986, Vyksa Steel Works (AO VSW) became the only manufacturer of electrically welded casing in Russia. Upgrades to ERW Shop 5 are necessary to meet customers’ most stringent requirements, such as manufacturing higher pipe grades and wall gages. The manufacturing process must meet international standards and the highest pipe quality requirements.
The threading and buck-on equipment is being replaced quickly. New threaded joints are being introduced in production. Protective coating equipment and additional inspection station installations are ongoing. The mill equipment is currently capable of making pipes with OD between 139.7 and 244.5 mm and wall gage of up to 10.7 mm, in grades of up to J55.
Replacing the mill and upgrading the ERW Shop 5 will help expand the product line, allowing the production of pipes ranging from 114.3 to 244.5 mm and wall gages of between 4.0 and 15.9 mm in grades of up to N80 per API 5CT and up to X80 per API Spec 5L.
The existing welding mill continues to operate, making the same amounts of product, while the new mill is being installed alongside it. This is why this project is one of the most complex ones being undertaken by the company at this time. The engineering and layout choices made will help replace the slitter in the future and install a heat treat area within the workshop without reducing the facility’s design capacity.
Mill upgrades will be performed in several stages. The preliminary stage is already complete; all the installations and utilities were moved off the construction site and additional bays have been constructed increasing the building area by 11,000 square meters.
In the first stage, the new mill will be installed and commissioned. Once this is complete, operations to insert the 114-245 pipe mill into the existing line will begin. Some equipment will be retained. Once the new equipment has achieved steady-state operation, the existing mill will be shut down and dismantled. It will be replaced by a finishing line that includes a flushing station, a gas cutter, inspection stations, specimen cut-out, UT and a pipe straightener. By the end of the second stage, the obsolete pipe mill will have been completely replaced with a new one.
Once upgraded, ERW Shop 5 will be capable of rapid change-overs to a different pipe OD, more precise process configuration for pipe forming and welding, helping introduce new grades of steel into the manufacturing process.
More state-of-the-art equipment will be installed in the line: weld seam ultrasound, ID seam visualisation, flying gate shears, pipe geometry measurements, etc. The use of a spiral looper will assure continuous mill operation and strip quality to expedite OD change-overs.
The project team has also developed unique technology by placing the newest equipment from different manufacturers in a single manufacturing line.
Maintenance during change-overs will become much easier. Automated software-controlled re-configuration of some rolling stand assemblies will help the work without swapping out tooling, such as rolls, and without automatically replacing roll components in other stands.
Revamping the 114-245 pipe mill will help the facility optimise the manufacture of electrically resistance-welded pipe and introduce a number of engineering innovations.
In the new mill production process, the metal strip will be unwound and fed into a flattener. The resulting strip will be straightened and brought to a butt welder, where the leading and the trailing edges will be trimmed at an angle and joined. To improve the quality of the butt weld, the bead will be milled away. To protect the butt weld from breakage, especially for the thicker walls, it will be heat-treated using an induction coil.
The strip with a smooth milled edge will then be transported to the forming area, where it is moulded into a tubular shape. Manufacturing facilities are based on advanced technology with the capability to adjust the pipe forming process while it is ongoing.
Next, the edges of the skelp are heated using a high-frequency induction welder. Once heated, the edges are crimped in the welding stand and joined. A more advanced welding control system will help take into consideration process parameter variations.
A marking device will then be used to apply a painted pilot line to the welded skelp. This helps automatically position equipment with respect to the pipe for subsequent process steps.
As the pipe is welded, an ID and an OD bead are formed on the weld. The new ID scarfer design chops up the ID bead, which makes it easier to remove during the flushing operation.
Once the ID and OD beads are removed, the weld is non-destructively tested by an ultrasound tester, as well as a scarfing quality inspection device. After UT, a crush test is performed and the correct selection of the heating parameters is verified, which is done in a quick analysis lab, and the outcome is used to decide whether the pipe is prime.
After final forming and welding, the pipe is delivered to weld annealing which has two modes of operation: normalisation (heating and subsequent air cooling) and quench and temper (heating, spray cooling, re-heating).
It is possible to position the weld at 12 o’clock using a stabiliser stand. Thereafter, the pipes are fed into a 4-stand sizing mill where they are sized to their final outside diameter and straightened. Following 2-stand straightening, the diameter of the pipe is measured and the pipe is transported to a printer that applies tracking information: pipe serial number, lot number, coil number, year of manufacture, shift designation.
Continuous pipe is cut to size using a flying cut-off. Pipe ends will be straightened in a stand-alone 10-roll straightener that is capable of several straightening modes and reduces pipe end irregularities significantly.
The facility will be equipped with a closed-circuit coolant-based tool cooling system which will protect the environment from contamination.
The ERW Shop 5 equipment upgrade will make the latest engineering advancements available for electrically welded pipe manufacturing. An automated production system will help monitor all the steps in the sequence and create a product of better quality.