Hot-rolled seamless steel pipe production process

     MPM pipe technology since 1958-1959 A. H. The Carl Metz (calmes) propose ideas and research for the preliminary test counting more than 30 years of history. Limit 30 years the MPM technology experience from testing to constantly improve the development process of mass production at the annual meeting of G in 1978 at the World pressure processing J. P. The Carl Metz wrote, manufacturing of Italy INNsE not count B'rgamo the MPM (MMlt Bu Stand Pipe MH, Limit the mandrel mill) basic process requirements of the unit summed up as follows: 

    (1) continuous casting billet as a tube to improve economic efficiency. 
    (2) using pressure to wear the 7L machine (PPM) is perforated in order to improve the quality of the perforated billet and increases billets singlet. 
    (3) extending coefficient smaller stretching machine in order to improve the metal dense and uneven thickness condition, and to reduce the types of billets specifications adopted. 
    (4) the use of fixed-reducing hunger group should have the following characteristics; finishing the steel pipe with a high extension coefficient. Rolling long tube, stretch reducing mill when necessary. Quality pipe rolling higher productivity. 
    At that time. J. P. Carl Metz once pointed out, MPM rolled tube technology is not an improvement of the existing rolling process, but a new rolling process, the British high yield, hot-rolled tube length, recovery rate and uses slab as the tube also. Since then the design than N5B MPM Tube Rolling After ten years of development, has become increasingly mature. From the process perspective, the scrolling speed limit by o. 5m / s to 1.5m / s, the extending rate from 7 down to 5 left. From the equipment perspective, early-the mandrel life problems exist, from the process, lubrication, cooling and mandrel processing and other aspects of the sub to solve. The transmission mode of the stopper means by hydraulic replaced by machinery, and the manufacturing process of the rack has been improved. Second aided process has been improved, including: mandrel pre-wear; the mandrel to return gRt support; to other roll without change rack; attention to the the perforated blank inside and outside surface quality, descaling spray chlorine withdrawal of boric acid salts and the like methods. Another punch from the early PPM pressure puncher Go PFM and the cRM (Rotary Piercing sails) co-exist, to cRM. The LRM who. Roll vertical configuration and roll horizontally arranged in two ways. Coexist. Punch background design is varied. 
    Etna standards, the company is also committed to limited dynamic the mandrel mill based juice the two sets MPMVl group with the holding point in the book the following: 
    (1) tube specifications of four kinds, only 1 less. 
    (2) the MPM of Hainan J-large godet Fu perforation sail. 
    (3) The two plants are used two roller extends machine. 
    (4) Hainan f 'pipe mill reported extends hunger and the hollow billet reducing mill parallel arrangement. 
    (5) Limit mandrel mill, Beijing Wal factory does not adopt a detached machine to solve the problem of detached and eight rack MPM 10 rack sizing mill tandem arrangement. 
    (6) Pipe Mill in Hainan widely both Limit operation. But also semi-floating or full-floating operation. 
    In addition to the Italy INNsE companies and U.S. Ai to be satisfied that the standard company original Steel Pipe Company is also actively MPM pipe technology and call the MRK-AR process. The gist of the process is: 
    (1) piercing mill with vertical rolls with a guide disc Diesel piercing machine, maximum elongation 4.2. Background simplify the design, which is characterized by the use of the immediate automatic replacement device. 
    (2) perforated preform of good quality, and the wall thickness deviation of soil 3. o 5. o%, wear 7L from time to extend machine, but to reduce tube specifications, with a hollow billet reducing sail.
    (3) MPM mandrel speed actual L 
    (4) and rolling tube elongation 3.82. 
    (5) the mandrel length of only 20.6m. 
    (6) sizing machine is actually a superposition of drive reduction machine. · 

 http://www.steelpipechn.com/Seamless-steel-pipe.html
    In recent years, MPM unit has become the model of choice for countries new steel pipe unit. As can be seen from Table 8-1, 18 white since 1980 and in the construction of foreign seamless steel pipe production line, there and 11 MPMTA group, demonstrated the strong vitality MPM unit. 
MFM rolling process development:    
(1) many of the old plant transformation MPM Tube Rolling Mill in lieu of the cycle-type pipe rolling mill, automatic tube mill and pipe jacking caught. 
(2) no arch continuous tube mill (MPM-sL), the device compact layout. 
(3) In the the MPM tube rolling machine using a hydraulic pressing apparatus, the roll can be automatically released when there have been a large rolling force. 
(4) pipe rolling mill in MPM rolling out the end of the set of non-contact thickness gauge, wall thickness automatic control. 
    Here we make a brief introduction of MINI-MPM process. 
    MINI; MPM process core is reduce the number of rack MPM mill tube, tolerances, received prison Higher. 
    MINI-MPM design, aimed at reducing investment and achieved the following production parameters: 
    small heating furnace capacity 70t; MPM mill capacity MPM outer diameter N1mm, the production of 70 eight; rolling pipe outside diameter of 251mm The yield was 35 Gener. 
    MINI-MPM process characterized by a larger extension of the use of tapered punch factor to reduce MPM mill 6t deformation amount. 5 rack so the program possible. Off pipe mill and sizing mill into one and cancel the reheating furnace. Using induction heating furnace, and to reduce energy consumption. Production of small diameter pipe, induction furnace plus - the death of a small extension coefficient stretch reducing mill, y <2, so that both flexible and savings.