High Strength Aisi 304 316 321 410 Welded round Tube Stainless
Steel Pipe For Fitness And Medical Equipment
Stainless Steel Pipes Introduction
Stainless steel tubing is one of the most versatile metal alloy materials used in
manufacturing and fabrication. The two common types of tubing are
seamless and welded. Choosing between welded vs. seamless tubing
primarily depends on the application requirements of the product.
In choosing between the two keep in mind that first the tubing must
be compliant with your project specifications and that secondly, it
must meet the conditions for which the tubing will ultimately be
used.
Knowing that distinction can also help in determining which tubing
is best for a given application, welded or seamless. The method of
manufacturing welded and seamless tubing is evident in their names
alone. Seamless tubes are as defined – they do not have a welded
seam. The tubing is manufactured through an extrusion process where
the tube is drawn from a solid stainless steel billet and extruded
into a hollow form. The billets are first heated and then formed
into oblong circular molds that are hollowed in a piercing mill.
While hot, the molds are drawn through a mandrel rod and elongated.
The mandrel milling process increases the molds length by twenty
times to form a seamless tube shape. Tubing is further shaped
through pilgering, a cold rolling process, or cold drawing.
Production process and characteristics of stainless steel seamless
pipe:
Stainless steel seamless pipes are divided into hot-rolled,
hot-extruded and cold-drawn (rolled) stainless steel seamless pipes
according to the production process.
hot rolled
Hot-rolled stainless steel seamless pipes are generally produced on
automatic rolling mills. After inspection and removal of surface
defects, the solid tube blank is cut into required lengths,
centered on the end face of the perforated end of the tube blank,
then sent to a heating furnace for heating, and perforated on a
punching machine. At the same time, the piercing continues to
rotate and advance. Under the action of the roll and the plug, a
cavity is gradually formed inside the tube blank, which is then
sent to the automatic tube rolling mill to continue rolling. meet
specifications. It is a relatively advanced method to produce
hot-rolled seamless steel pipes with continuous pipe rolling mills.
hot extrusion
The hot extrusion method is to place the heated tube blank in a
closed extrusion cylinder, and the perforated rod and the extrusion
rod move together to extrude the extrusion part from the smaller
die hole. This method can produce steel pipes with smaller
diameters.
Cold drawn (rolled)
In order to obtain seamless pipes with smaller size and better
quality, cold drawing (rolling) must be used. Cold drawing
(rolling) is usually carried out on a two-roll mill, and the steel
pipe is rolled in an annular pass composed of a variable-section
circular hole groove and a stationary conical head. Cold drawing is
usually carried out on a single-chain or double-chain cold drawing
machine of 0.5 to 100T.
Hot rolling is relative to cold rolling, cold rolling is rolling
below the recrystallization temperature, and hot rolling is rolling
above the recrystallization temperature. Hot rolling can damage the
forging structure of the ingot, refine the grains of the steel, and
eliminate the defects of the microstructure, so that the steel
structure is dense and the mechanical properties are improved. This
improvement is mainly reflected in the rolling direction, so that
the steel is no longer isotropic to a certain extent. The bubbles,
cracks and porosity formed during casting can also be welded under
the action of high temperature and pressure.
Cold drawn (rolled) stainless steel seamless pipe has high
production efficiency, short production cycle, uniform wall
thickness, good surface quality, high yield and low production
cost. However, due to the reason of only one annealing, the tube is
prone to cracks, and some deep processing such as bending cannot be
carried out. Moreover, the production range of rolled tubes is
limited, and the general production is ¢25mm-168mm


Stainless Steel Pipes Parameter
Product Name | 304 stainless steel seamless tubing |
Steel Grade | 300 series |
Standard | ASTM, ANSI, JIS,DIN,EN |
Material | 304, 304L, 316 |
Surface | Polishing,annealing,pickling,bright |
Technique | Cold rolled |
Wall thickness | 1mm-150mm(SCH10-XXS) |
Outside Diameter | 6-2500mm |
Lead time | 8-14 days after receipt of advance payment |