TP304, TP304L, SUS304, SUS304L capillary for medical tube,
electronic microtube etc
TP304, TP304L, SUS304, SUS304L welded or seamless capillary.
2 EQUIVALENT DESIGNATION
UNS S30400, X5CrNi18-9, X5CrNi18-10, W.Nr. 1.4301, 0Cr18Ni9
UNS S30403, X2CrNi18-9, X2CrNi19-11, W.Nr. 1.4306, 1.4307,
(1)Medical tubes such as syringes for injections, puncture
(2)All kinds of industrial tubes, small precision stainless steel
tubes, dispensing syringes.
(3)Temperature guide tube, electronic thermometer, thermocouple
protection tube, barbecue temperature probe tube, instrument
protection tube, sensor tube, barbecue rub tube, thermostat tube,
instrument tube, thermometer stainless steel tube, microbiological
(4) Core protector, pen holder
(5) Various electronic microtubes, optical fiber accessories,
(6) Horological industry, T-bars with studs or screws, watch belt
fittings, gem punches needle
(7) All kinds of antenna tubes, automobile tail antenna tubes, pull
rod antenna tubes, stretch rod, mobile phone stretch antenna tubes,
miniature antenna tubes, all kinds of stainless steel antenna.
(8) Stainless steel tubes for laser engraving equipment
(9) Fishing tackle pipe, fishing rod pipe
(10) All kinds of food and beverage industry pipe, feeding pipe
(11) Various stylus tubes, cell phone stylus, computer stylus tubes
304 stainless steel is the most widely used chromium - nickel
stainless steel, with good corrosion resistance and heat
resistance, low temperature strength and mechanical properties,
good hot working property such as stamping and bending, no heat
treatment hardening (operating temperature: -196 ~800), no
magnetism. It has corrosion resistance in the atmosphere. If it is
industrial atmosphere or heavily polluted area, it should be
cleaned in time to avoid corrosion. Good machinability and
weldability. It is suitable for food processing, storage and
transportation, plate heat exchanger, corrugated tube, household
articles, auto spare parts, medical instruments, building
materials, chemistry, agriculture, ship parts, etc.
SUS304L has all the features of SUS304. It has excellent corrosion
resistance, heat resistance, good corrosion resistance after
welding or stress relief, and good deep drawing and polishing
5 CHEMICAL COMPOSITION (wt%):
5 PHYSICAL CONSTANTS
Density: 7.93 g/cm³
Specific heat capacity (0~100°C,KJ·kgK): 0.50
Thermal conductivity: (W·m·K):(100℃)16.3,(500℃)21.5
Coefficient of linear expansion: (10·K):(0~100℃)17.2,(0~500℃)18.4
Electrical resistivity(20℃, 10Ω·m/m): 0.73
Longitudinal modulus of elasticity (20,KN/mm): 193
6 MECHANICAL PROPERTY
The material shall conform to the requirements as to tensile
properties specified in Table 2.
These mechanical properties apply to tubing 1/8 in. (3.2 mm) and
larger in outside diameter by 0.015 in. (0.38 mm) in wall thickness
Smaller sizes are available meeting the minimum tensile strength
specified in Table 2; however, yield strength is not generally
determined on such sizes, and the minimum elongation shall be 25 %.
|Grade||Recommended heat treatment||Tensile strength σb MPa||Yield strength Rp0.2 %||Elongation δ5 %||Hardness|
|TP304||1010-1150°C rapid cooling||≥520A||≥205AB||≥35B||≤187HB|
|TP304L||1010-1150°C rapid cooling||≥520A||≥205AB||≥35B||≤187HB|
A Grades TP 304L shall have a minimum tensile strength of 70 ksi
(485 MPa) and a minimum yield strength of 25 ksi (170 MPa).
B Yield strength is not generally determined on tubing sizes
smaller than 1/8 in. (3.2mm) in outside diameter or thinner than
0.015 in. (0.38 mm) wall, so yield strength is not required on such
sizes. Also, the minimum elongation required on these smaller or
thinner sizes is 25 %.
7 HEAT TREATMENT
The purpose is to make the carbides fully dissolved and retained in
the austenite at room temperature, so as to obtain single phase
austenite microstructure at room temperature, so that the steel has
the highest corrosion resistance.
The heating temperature of solid solution treatment is generally
higher, between 1050-1100°C, and is adjusted appropriately
according to the carbon content. As the thermal conductivity of
TP304 is very poor, not only through preheating and then quenching
heating, but also in the solid solution treatment (quenching
heating) of the heat preservation time is long. Special care must
be taken to prevent carburization during solid solution treatment
as carburization will increase the intercrystalline corrosion
tendency of TP304 steel. Cooling medium, generally use water. The
microstructure after solid solution treatment is generally
single-phase austenite, but for stainless steel containing Ti,
Niobium and Molybdenum, especially for castings, it also contains a
small amount of ferrite. The hardness after solid solution
treatment is generally around 135HBS.
Stress relieving annealing
In order to eliminate the residual stress after cold processing,
stress relieving annealing is carried out at a lower temperature.
Generally heated to 250-425°C, 300-350°C is often used. For steel
without Titanium or Niobium, it should not exceed 450°C to avoid
precipitation of chromium carbide and cause intergranular
In order to eliminate the residual stress after welding and the
sensitivity of steel to stress corrosion, the treatment is
generally carried out at a higher temperature. Heating temperature
is generally not less than 850°C. For steel containing Titanium or
Niobium can be directly cooled in the air. For steel that does not
contain Titanium or Niobium should be cooled with water to 500°C
before being cooled in air.
In order to prevent the austenitic stainless steels containing
Titanium and Niobium from reducing their intergranular corrosion
resistance due to the reduction of TiC and NbC during welding or
solid solution treatment, the stainless steels need to be heated to
a certain temperature (the temperature makes the carbide of
chromium completely dissolve in the austenite, while TiC and NbC
only partially dissolve) before slow cooling. In the cooling
process, the carbon in the steel is fully combined with Titanium
and Niobium, and stable TiC and NbC are precipitated out, while
chromium carbide is not precipitated out, thus eliminating the
intercrystalline corrosion tendency of TP304 steel.
Tube blank → Peeling → Blanking → Heating → Hot piercing → Cooling
→ Finishing → Pickling → Lubricating
→ Cold rolling → Degrease → Heat treatment → Straightening → Tube
cutting → Pickling → Inspection → Packing.
Tube blank → Peeling → Blanking → Inner hole drilling → Lubricating
→ Cold rolling or drawing → Degrease
→ Bright annealing → Straightening → ID and OD surface polishing →
Inspection → Packing.
Permissible variations in dimensions
|Up to, but not including 3/32(0.094) in. (2.38 mm)||+0.002|
|3/32 (0.094) in. (2.38 mm) but not including 3/16 (0.188)in. (4.76
|3/16 to, but not including, 1/2(0.500) in. (12.70 mm)||+0.004|
10 FLARING TEST
A section of tube approximately 4 in.(101.6 mm) in length shall
stand being flared with a tool having a 60°included angle until the
tube at the mouth of the flare has been expanded to the following
percentages without cracking or showing flaws:
|Ratio of inside diameter to outside Diameter||Minimum expansion of inside diameter, %|
11 Hydrostatic, Air Underwater Pressure Test, or Nondestructive
Each tube shall be subjected to the hydrostatic test, air
underwater pressure test, or nondestructive electric test. The
type of test to be used shall be at the option of the manufacturer,
unless otherwise specified in the purchase order.
Each tube shall be subjected to a hydrostatic test at a test
pressure not exceeding 1000 psi (6.89MPa).
Air Underwater Pressure Test
Each tube shall be subjected to an air underwater pressure test, at
a test pressure as given by the following equation or 500 psi (3.4
MPa), whichever is less: P=2St/D
P = air pressure, psi or MPa
S = allowable fiber stress of 16,000 psi (110.3 MPa),
t = specified wall thickness, in. or mm, and
D = specified outside diameter, in. or mm.
Nondestructive Electric Test
Each tube shall be subjected to a nondestructive electric test that
is capable of detecting imperfections with a
depth exceeding 10 % of the wall thickness or 0.002 in. (0.05mm),
whichever is greater. Testing will not be required on sizes under
0.125 in. (3.18 mm) in outside diameter. However, at the option of
the purchaser, tubing to be drawn to a diameter under 0.125 in. may
be tested while in the range from 0.156 in. (3.97mm) to 0.125 in.
outside diameter, and any defects that are found shall be culled
out before any further reductions are made.
12 PRODUCT CAPACITY
Surface:2B, BA, Mirror, sandblasted surface, passive surface.
Annealing surface,fine drawing bright surface Ra≤0.8μm,finely
polished ID and OD Ra≤0.2-0.4μm. (possible Ra 0.1μm at request).
13 STANDARD SPECIFICATION
GB/T 3090 Stainless steel small diameter seamless steel tube
GBT 18457 Stainless steel needle for manufacturing medical
GB 4234 Stainless steel for surgical implants
YBT 4513-2017 Welded stainless steel tubes for medical gases and
ASTM A632 Standard Specification for Seamless and Welded Austenitic
Stainless Steel Tubing (Small-Diameter) for General Service
ISO 5832-1-2016 Implants for surgery metallic materials - Part 1
Wrought stainless steel
ISO 9626-2016 Stainless steel needle tubing for the manufacture of
medical devices requirements and test methods
14 COMPETITIVE ADVANTAGE
(1) More than 50 years experience of research and develop in high
temperature alloy, corrosion resistance alloy, precision alloy,
refractory alloy, rare metal and precious metal material and
(2) 6 state key laboratories and calibration center.
(3) Patented technologies.
(4) High performance.
15 BUSINESS TERM
|Minimum order quantity||Negotiable|
|Packaging details||Water prevent, seaworthy transport, plastic box|
|Mark||As per order|
|Delivery time||60-90 days|
|Payment terms||T/T, L/C at sight, D/P|
|Supply ability||20 metric tons / Month|