Steel wire rods price from Sha Steel Plant
Date: May 21, 2022

Steel wire rods price from Sha Steel Plant
Date: May 11, 2022

Lead adhesion on steel wire surface is a serious problem in annealing and patenting, because the following pickling treatment can hardly remove the lead residue and phosphating film can either hardly be closely compact on steel wire, which could lead to die block and steel wire breakage in subsequent drawing as well as lead excessive consumption.

In order to avoid above accident and ensure steel wires always in perfect state for followed production, we summarized a fewer of key points as below.
1) Confirm the steel wires should be in good surface without any scratch before annealing and patenting.
2) We should adjust the furnace temperature between 900 and 1000 degrees in centigrade against various steel wire sizes and finally to settle the wire temperature should be 900-910 centigrade.
3) Set the temperature of lead liquid in tank be at 550 centigrade and turn up to 560 centigrade only if lead adhesion still available and which should be effective.
4) Lead tank should be covered tightly without any parts open in the air, just in order to avoid steel wire oxidized and excessive viscosity of lead under oxidization.
5) Enlarge the exit end angle of lead tank, for instance from 30 up to 45 degrees, in order to help the lead residue on steel wire surface fall off easily.
6) We should insist on clearing up the furnace and checking the wire conveyor roller in good state without any crack once a month, in order to prevent steel wires from unexpected scratch.

1) To calculate the weight of wire rope (KG/100m)
Formula: M=K X D X D
M=Reference weight of wire rope (KG/100m)
K = certain coefficient of weight (different coefficient for different rope construction)
D = diameter of wire rope
For instance
Wire rope: 6X7-FC -10mm (Nature fiber core), as we know its K=0.351, and the reference weight = 0.351X10X10 = 35.1 (KG/100m)

2) To calculate the wire rope minimum breaking load(KN)
Formula: F = (K X D X D X R) / 1000
F = wire rope minimum breaking load by actual test (KN)
K = certain coefficient of weight (different coefficient for different rope construction)
D = diameter of wire rope
R = tensile strength of wire rope (MPA)
For instance
Wire rope: 7X7-10mm, as we know K=0.359, R=1770, and the minimum breaking load F = (0.359X10X10X1770)/1000=63.5 KN

There are certain differences in some respects for steel wire processed between lead patenting and water quenching.
1. Pollutant
(a) Lead patenting
The main pollutant from lead patenting is lead steam and lead oxide. Annealing one ton of steel wire needs to consume 3-5kg of lead and among which 0.05-0.20kg of lead is steamed into atmosphere while the remains changed into lead oxide. The residue of lead oxide and lead steam are both inevitably coming even though covering agent is applied. It is necessarily required to clear away the covering agent on every two months and that may cause recycling pollution.
(b) Water quenching
The main pollutant is just the quenching bath with ferric oxide involved. However, the quenching additive is of food grade and needs eliminated on every half year which can be easily treated without any pollution.

2. Technical
(a) Lead patenting
In the lead bath, the constant temperature is controlled at 500-550 degree centigade and the sorbite conversion rate for steel wire can reach 90-98%, which ensure the wires in good quality and stability.
(b) Water quenching
In the steaming film, the temperature is controlled at 500-600 degree centigrade and the sorbite conversion rate for steel wire can reach 90-95% but with more serious technical demand.

3. Operation
(a) Lead patenting
Lead temperature is the only parameter need control.
(b) Water quenching
The temperature, concentration, impurity and more other parameters in quenching bath need strictly control.

4. Others
Steel wires through lead patenting can achieve higher tensile strength of 60-100mpa and finally enjoy more flexibility and toughness than those through water quenching. In addition, lead patenting is a little bit costly than water quenching on investment.

Carbon steel wire is of non-alloy wire and its manufacturing technique is conventional as follows.

Sample:
High carbon spring steel wire
Target wire size of 1.00mm with T/S 1960-2300 Mpa

Our essential process:
Step 1: Confirm the steel wire rods with grade of 70# or 72A# as customer required from China qualified steel plants.

Step 2: Confirm the former working process of annealing, patenting and phosphating are qualified for following wire drawing.

Step 3: Confirm the inlet wire diameter should be 3.10 mm, since the general compression ratio controlled in 90-95% is preferable for carbon spring wire.

Step 4: Confirm the dies in the tank with right sizes and rows of arrangement for wire drawing.

Step 5: The spring wire straightener should be installed in the wet wire drawing machine in order to achieve the perfect straightness circle.

It is related to manufacturing technology and we give an illustration as follows.

Sample:
Stainless steel spring wire (SS 304H)
Target wire size of 0.20mm with T/S 2050-2400 Mpa

Our essential process:
Step 1: Confirm the wire rods with grade of SS 304 or SS 304H and the carbon content of 0.06-0.08% in percentage as customer required from China qualified stainless steel plant.

Step 2: Confirm the former working process of pickling and annealing are qualified for following wire drawing.

Step 3: Confirm the inlet wire diameter should be 0.60mm, since the general compression ratio controlled at 80-90% is preferable for SS spring wires.

Step 3: Confirm the dies is the right choice as we required, including the dies material, dies compression angle and dies belt length ratio.

Step 4: Confirm the dies in the tank with righ sizes and rows of arrangement for wire drawing. For instance, 0.20→0.22→0.24→0.27→0.30→0.34→0.38→0.43→0.48→0.54 (totally 10 dies in use is better)

Step 5: The spring wire straightener should be installed in the wire drawing machine in order to achieve the perfect straightness circle.

Since the last three dies (0.20/0.22/0.24) are really more important for final product, it is necessary for us to keep close observation and timely replace qualified dies during manufacturing.

Above is just part of SS spring wire technical knowledge in working, and honestly hope it could be helpful to anyone if require.

(A) Alloy and non-alloy elements
Carbon steel wire has almost non-alloy elements mainly for C, Si, Mn, S, and P.
However, stainless steel wire has various alloy elements especially for Cr and Ni that occupy 12% Minimum in percentage.
Various chemical elements lead to large discrepancy on mechanical property and working process for final use.

(B) Corrosion resistance
Carbon steel wire apparently shows weak anti-corrosion ability due to its higher carbon component. In order to avoid any rust, slushing oil is necessarily in conventional use for un-galvanized carbon wires during storage and transportation.
On the other hand, stainless steel wire has quite stronger anti-corrosion ability to meet market consumption, especially for SS 300 series.

(C) Magnetism
Carbon steel wire possesses obviously strong magnetism. Stainless steel wire has none or weak magnetism for both SS 200 series and 300 series, but there is distinct magnetism for SS 400 series on account of its martensitic structure.

(D) Wire surface
Carbon steel wire surface is normally black and shiny, however stainless steel wire is always in silver bright color (Some part of SS wires with dull surface for special application) due to its abundant alloy elements involved, as well as its clearly smooth surface.

SS 201 and 202 are both of high manganese (Mn) stainless steel, in which much manganese come into use instead of nickel (Ni) and get the nearly same effect as 304 in some weakly anticorrosion environment. Additionally, due to the cheaper cost, SS 200 series still remain the competitive advantage to satisfy those certain needs in market.

SS 301,304 and 316 are all of classic stainless steel, who have been enjoyed most popularity and widely used in world.

SS 200 Series and SS 300 series are belonged to Austenite structure with nonmagnetic or weakly magnetic property, which is distinguished from SS 400 series who are of Martensitic structure with strong magnetism.