SEAMLESS LINE PIPES

     Seamless line pipes used for construction of long distance pipelines for combustible liquids and gases, nuclear station pipelines, heating system pipelines, general-purpose pipelines.

DISTINCTIVES FEATURES

-          Line pipes are manufactured of metal in-house produced and smelted in the electric furnace, treated with synthetic slags and cast by continuous casters. The applied steel making process ensures the achievement of chemically pure steel with reference to sulphur and phosphor contents providing high tensile, ductility and corrosion resistance properties of pipes to be operated at low temperatures in various corrosion media.

-         Rolling using a press piercing mill and continuous mill equipped with a fixed mandrel allows strict measurement tolerances to be obtained and ensures a lack of pipe body and surface defects.

-          In order to achieve high tensile and ductility steel as well as its required structure, providing a high corrosion resistance in various corrosion media, pipes are heat treated in a computerized walking beam furnace. 70% of oil line pipes are subject to heat treatment.

-          Pipes are inspected for internal and external flows by automatic non-distructive testing of ultrasonic and electromagnetic inspection. Pipe ends inspection after beveling is done by magnetic-fluoroscopic flaw detection.

-    While manufacturing seamless line pipes ensures testing of corrosion-resistance properties through hydrogen included cracking method under NACE MR 02-84 and sulphide stress corrosion cracking method under NACE MR 01-77.

Standards and Application

 SEAMLESS CASING PIPES

Casing pipes used for casing for oil and gas wells

DISTINCTIVE FEATURES

-          Casing pipes are manufactured of metal in-house produced and smelted in the electric furnace, treated with synthetic slags and cast by continuous casters. The applied steel making process ensures the achievement of chemically pure steel with reference to sulphur and phosphor contents providing high tensile, ductility and corrosion resistance properties of pipes to be operated at low temperatures in various corrosion media.

-         Rolling using a press piercing mill and continuous mill equipped with a fixed mandrel allows strict measurement tolerances to be obtained and ensures a lack of pipe body and surface flows. Wall thickness is inspected throughout the pipe length by the ultrasonic unit.

-          Pipes are heat-treated in a computerized walking beam furnace. Steel grades and heat treatment regimes applied allow high-strength pipe to be obtained.

-          Automatic ultrasonic and electromagnetic nondestructive inspection is performed to detect pipe outside and inside flows. Inspection of pipe ends before threading and couplings after treading is realized by magnetic-fluoroscopic flaw detection.

-          Threаding of pipes and couplings is perfomed by numerical control machine tool. The facilities allow the production of both standard ("Buttress") and up-to-dated high-sealed threads of "Premium" type. Every threaded pipe end and every coupling is controlled with a thread gauge.

Standards and Application

SEAMLESS PIPES FOR GENERAL PURPOSE

Used for vessels manufacturing and pipelines laying, in mechanical engineering and instrumental engineering; pressure operating pipes, steam, water, gas, air.

Pipes are manufactured of metal in-house produced and smelted in the electric furnace, treated with synthetic slags and cast by continuous casters. The applied steel making process ensures the production of pure metal as far as sulphur and phosphor contents.

Standards and Application

SEAMLESS PIPES FOR POWER INDUSTRY (BOILER PIPES)

The boiler pipes are produced by hot extrusion. Used for steam boilers and pipelines with high and supercritical steam parameters.

DISTINCTIVE FEATURES

Research results show the following advantages of hot extrusion method over traditional hot rolling:

-          pressure loss per unit of conventional lenght during gas pipeline transportation for pressed pipes is 40% less than for rolled pipes;

-          wear and tear of lathe tool during turning for pressed pipes is 10-25% less than for rolled pipes;

-          during the same service period of steam boilers pressed pipes show four times less scale deposit than rolled pipes;

-          pressed pipes have higher average strength (5-7%) and plasticity (10-14%) values than rolled pipes, so that the possibility of their destruction is 5 times less than of rolled pipes.

Standards and Application

SEAMLESS PIPES FOR BEARING

Production of internal and external rings for ball and roller bearings. Wide range of produced hot-deformed pipes, including cold-rolled range of size. High quality of metal microstructure provided by the designated temperature at the end of rolling and up-to-date means of heat treatment.

Standards and Application

Seamless Line Pipe

Seamless carbon and alloy steel tubes are normally in both hot-rolled and cold-drawn condition.

The full range consists of:

1.      Hot finished seamless line pipe for the conveyance of water, gaseous and liquid             hydrocarbons used in the oil and natural gas industry.

2.      Hot finished seamless casing and tubing used in the OCTG industry.

3.      Cold-drawn precision seamless tubes for the manufacture of drill rods, boiler tubes and             mechanical tubing. T

1. Hot-finished seamless line pipe

Seamless line pipe is produced to comply with the specifications API 5L, PSL1 and PSL2, ASTM A106 and ASTM A53. Material can also be supplied to the equivalent EN 10208 Part 2. The product range is limited to the sizes given in table 1, with wall thickness to ANSI B36.10.

Steel grades

Three basic steel grades are used for the production of the different grades of material in the API 5L specification. The main chemical elements will comply with the following maximum limits:

Chemical composition PSL1

Chemical composition PSL2

Stricter requirements on chemical composition are often applied at a customer’s request.

Dimensional tolerances

The dimensional tolerances used are in strict accordance with the API 5L specification:

Mechanical properties

The line pipe supplied by Mittal Steel South Africa is in accordance with the API 5L requirement for mechanical properties.

All hot-finishing processes are done and completed above a temperature of 860ºC. The hardness of the material is in all instances below 22HRc, thus complying with the NACE MR 01-75 requirement for carbon steels.

End preparation

All line piping is square cut to the tolerance specified and bevelled to ANSI B16.25. An angle of 30º

(-0º, +5º) and a landing of 1,6 mm, ±0,8 mm is applied. Schedule 160 material is supplied without bevelling.

Non-destructive testing

All material is hydrostatically tested to the requirements of API 5L. The standard pressure is limited to 20,7 MPa (3000 psi).

Electro-magnetic inspection is carried out on all line pipes. The reference notch used is 12,5% of nominal wall thickness. On request, ultrasonic testing to API 5L or API 5CT may be done with a reference notch of either 5% or 10% of nominal wall thickness.

Coating

A choice of black or clear varnish exists for coating of the line pipe. This coating is a solvent-deposited non-toxic phenolic PVB that can be used as a base coat for most overcoats. This coating provides atmospheric resistance to oxidation for a period of 6 to 12 months.

Marking

Identification marking is applied to every pipe by means of paint stencilling along the length of the pipe and is in full accordance with Appendix I of API 5L. Colour band marking may be applied at a customer’s request. Additional information pertaining to the bundle is printed on a weatherproof plastic label attached to the bundle.

Bundling

Material is supplied in hexagon bundles of between 2 and 4 tons to the following schedule: