Production process flow
Round tube blank → heating → piercing → three roll cross rolling, continuous rolling or extrusion → pipe stripping → sizing (or reducing) → cooling → straightening → hydrostatic test (or flaw detection) → marking → warehousingProduction methods
According to different production methods, it can be divided into hot-rolled pipe, cold-rolled pipe, cold drawn pipe, extruded pipe, etc. hot-rolled seamless pipe is generally produced on the automatic pipe rolling mill. The solid pipe blank is checked and cleared of surface defects, cut into the required length, centered on the end face of the perforated end of the pipe blank, and then sent to the heating furnace for heating. It is perforated on the piercer. It rotates and moves forward at the same time, Under the action of the roll and the plug, a cavity is gradually formed inside the pipe blank, which is called the rough pipe, and then sent to the automatic pipe mill for continuous rolling. Finally, the wall thickness is adjusted by the equalizer, and the diameter is determined by the sizing machine to meet the specification requirements. Using the continuous pipe mill to produce hot-rolled seamless steel pipe is a more advanced method. If you want to obtain seamless pipe with smaller size and better quality, Cold rolling and cold drawing or a combination of both must be adopted. Cold rolling is usually carried out on a two high rolling mill. The steel pipe is rolled in an annular pass composed of variable section circular hole groove and fixed conical plug. Cold drawing is usually carried out on a single chain or double chain cold drawing machine, that is, the heated pipe blank is placed in a closed extrusion cylinder, and the perforated rod moves together with the extrusion rod, The extrusion part is extruded from the smaller die hole, and the steel pipe with smaller diameter can be produced by this method. 10# seamless steel pipe 20# seamless steel pipe 45# seamless steel pipe Sa106b seamless steel pipe ST45.8 - Ⅲ low alloy seamless steel pipe 20Cr, 40Cr, 16Mn low alloy seamless steel pipe Q345D low temperature alloy seamless steel pipe 27SiMn low alloy seamless steel pipe 12Cr1MoVG alloy pipe 15CrMo alloy pipe 10CrMo910 alloy pipe Cr5Mo alloy pipe A335p11 alloy pipe 10CrMo910 (P22) alloy pipe A335P91 (T91) alloy pipe Gangyan 102 (12Cr2MoWVTiB) Structural pipe: (GB / t8162-2008) Fluid pipe: (GB / t8163-2008) Medium and low pressure boiler tubes: (GB / t3087-2008) High pressure boiler tubes: (GB / t5310-2008) Petroleum cracking pipe: (GB / t9948-2006) Hydraulic prop pipe: (GB / t17396-1998) Special pipe for chemical fertilizer: (GB / t6479-2000) Steel pipe for drilling: (GB / t9808-2008) Marine pipe: (GB / t5312-1999) Alloy pipe: (GB / t8162-2008) High pressure alloy pipe: (GB / t5310-2008) and a series of steel pipe products. Materials: 10 #, 20 #, 35 #, 45 #, 20g, 20gr-50gr, 16mn-45mn, 27SiMn, Cr5Mo, 12CrMo (T12), 12Cr1MoV, 10CrMo910, T91, 15CrMo, 35CrMo, 40CrMo, etc.Four basic modes
Small diameter thick wall seamless pipe refers to the steel pipe with small ratio of outer diameter to wall thickness. The minimum diameter can reach 3mm and the minimum wall thickness can reach 1mm. Weight formula of small diameter thick wall seamless steel pipe: [(outer diameter wall thickness) * wall thickness] * 0.02466 = kg / M (weight per meter)
It is mainly used as petroleum geological drilling pipe, cracking pipe for petrochemical industry, boiler pipe, bearing pipe, high-precision structural pipe for automobile, tractor and aviation, etc. The materials of small-diameter thick wall seamless steel pipe include: 10#, 20#. 25 #, 35 #, 45 #, 16Mn, etc.