Production technology

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The plant comprises two manufacturing shops: pipe rolling (TPC) and pipe drawing (TVC). It also comprises of central plant laboratory (CZL), metrological laboratory, maintenance department and management part (office).
Pipe rolling shop is purposed for manufacturing of hot-formed pipes and tubes with outer diameter of 70-168 mm and wall thickness of 4-30 mm, 1/5-13 meters in length made of carbon, alloyed stainless, bearing, boiler and other steel grades along with titanium alloys.

Pipes are made from pipe billet 90-150 mm in outer diameter.

In this shop there are 6 main manufacture departments:

- manufacture preparation department;
- rolling department;
- general pipes finishing department;
- boiler pipes finishing department;
- heat treatment department;
- ready-made product packing and shipping department.

For pipe rolling the shop uses billets cut into multiple lengths with saws or press-scissors.

Before rolling the pipe billet is centered in cold condition or just before the piercing in hot condition. The rolling of the pipes is performed on the pipe rolling mill TPA “140” which consists of two-roll piercing mill, automatic mill, 2 enrolling mills and 2 caliber mills (with 7 and 10 crates).

After the rolling pipes are cooled on the cooling table and then transferred to one of the finishing departments where they are straightened on 5-roll mills.

In the shop there are chamber and normalization furnaces for heat treatment of pipes.

After he straightening pipes are sent to cutting and when needed to another finishing department.

At the final finishing pipes are checked by the quality department staff: all the required parameters are verified along with steel grade analysis there are performed all the tests required together with non-destructive control procedures.

At the ready made product department the pipes are protectively coated, packed, weighted and stored up to being shipped to the customer.

The pipe drawing shop is purposed for manufacturing of cold formed pipes from a wide range of carbon steel grades 10, 20, 35, 45 and alloyed steel grades 10G2, 15HM, ShH-15, 30H2SA, 15H, 20H, 40H, 12H1MF, 12HNZA and others, in lengths 1,5-13 meters and sizes of 6-95 mm in outer diameter and 0,5-12 mm in wall thickness.

This shop is equipped with a set of main and auxiliary machinery for manufacturing the abovementioned scope of pipes in full accordance to all the requirements of both native and international standards: GOST, DIN, EN, ASTM and TU.

In this shop there are the following manufacturing departments: manufacturing preparation department, pickling department, cold rolling department, cold drawing department, heat treatment department, boiler pipes finishing department, general purpose pipes finishing department, ready made product packing and shipping department.

Besides the main manufacturing departments in this shop there are also auxiliary departments: mechanics department, energetic department, tools workshop etc.

Finishing departments are equipped with a set of machinery for straightening, cutting, visual inspection and non destructive testing of the pipes.

The technological process of cold formed pipes manufacture begins with initial check of the incoming hot rolled pipe intermediate billet for accordance to requirements of the standards on its labels and marking.

After weighting each pipe billet bundle is tagged with indication of steel grade, heat number, weight, manufacturer shop and inquiry number.

Upon the inquiry pipe billets are cut into required lengths or prepared for further manufacturing without cutting. All the pipes sent into manufacture are spark test verified for steel grade.

The visual inspection of inner and outer surfaces, dimensions of the billet and its start into manufacture are effected in full accordance to technological instructions. Each bundle of pipe billets which entered into manufacture is weighted and tagged.

Intermediate machining of the pipes is effected according to working schedule stipulated in technological instructions.

pic 8Manufacture of pipes and tubes from the billet and up to ready made condition is performed strictly according to the technological routes where are indicated among other data the initial billet dimensions, intermediate dimensions, finished dimensions and the method of forming and heat treatment for each of the sizes.

The majority of cold formed pipes are made by cold drawing on HPT mills in 1-3 draws or by short mandrel drawing in 1-2 draws with consequent mandrelless drawing.

Before the forming on the HPT mills the pipe billet is lubricated and before short mandrel drawing it is phosphated and only then lubricated.

Pipe drawing on HPT mills is effected with usage of technological lubricants made on the basis of vegetable oils mixed with talc. Tools cooling is effected through cooling-lubricating liquid.

For the recovery of plastic properties of the pipe metal after forming tubes and pipes are heat treated in gas furnaces at the temperature of 700-980°C (depending on steel grade and purpose of the pipes).

Scale removal from the surface of heat treated pipes is effected by means of pickling in sulfuric-nitric (with inhibitor) solution.
Straightening of the pipes is effected mainly on obliquely roll mills.

Pipe quality control, cutting into required lengths are effected in pipe finishing departments. The type of the control check is stipulated by product technical standards requirements.

The pipes and tubes accepted by quality control department and proceeded through all control verifications required by the customer are protectively coated by sinking into the tank with preserving solution.

The ready-made bundles are packed, weighted, tagged and stored on the ready-made product storage before being shipped to the customers.


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