1.1 General Description
the Galvanising/Galvalume line, with functions as degreasing, annealing,galvanizing, galvalume，skin pass, tension leveler, fingerprint resistant coating
(AFP), Chromate, / passivating, oiling, etc. Thickness: 0.3-1.25mm×700-1250mm.
The reference strip is 0.6x1100mm (CQ) with process speed of 120mpm, capacity
per hour is Max. 37.3ton/hr. The production line whole length: 235m. Products
grade:CQ,DQ,DDQ.The GI product would refer to GB/T2518-2019. The GL
product would refer to GB/T14978.
1.2 Proposal Highlights
- Entry horizontal looper and exit vertical looper equipped with tension control system and capacity absolute measuring and controlling system to ensure the line running safety, high speed and stable.
- Alkali degreasing process combines with electrolytic degreasing, to ensure efficient degreasing, long brush roll life and low emission.
- Horizontal type radiant tube heating recrystallized annealing method is adopted for manufacturing.
- Using light ceramic fiber pre-compress module bricks as the inner lining of annealing furnace, which has the advantage of quick furnace building and low thermal inertial.
- HNx jet cooling with VVVF jet cooling blower, which can get the effect of quick and uniform cooling, the temperature of strip coming into the zinc pot can be controlled accurately.
- Jetting-flow type ceramic induction heating zinc pot, they have the advantage of quick heating, temperature equalization, long working life and few zinc dross etc.
- Sink roll in zinc pot is made by special heat resistant and anti-corrosion alloy material, it can against corrosion of melted zinc. Scraper shall be provided to make sure the better quality.
- Single jet air knife is used for coating layer quality and coating weight controlling conveniently.
- 4-Hi Skin pass can improve the strip surface quality, remove yield point elongation, and improve cold punch performance.
- Tension leveler is with 2-bending and 2-levelling, used to improve the strip shape and surface quality.
- The CPC, EPC sensor and controller will be Beijing EMG brand products, ensure the stable operation of the line.
- EMG brand EPC is equipped on tension reel, which consists of optical CCD pro 30000 measuring system, digital controller, transducer and servo valve, etc. The EPC can implement the function of staggered winding.
- AC/ VF transmission control system, which has good human-machine interface, it is easy to maintenance.
1.3 Line Specification
1.3.1 Process
According to the function of the production line and the process sequence of the strip, the line are divided into entry section, processing section and exit section. The entry section mainly includes pay off reel, shear, welding and degreasing and hot water rinsing. The processing section mainly includes annealing, galvanizing, skin pass, tension leveler, antifinger coating section, and thus finishes the technical processing of the strip. The exit section takes charge of shearing, the strip will be rewinding as the required weight.
The technical flow show as follow:
Coil loading →pay-off reel →entry shear →welder→ entry looper →degreasing section(alkali brushing +electrolytic degreasing+ alkali brushing+ water rinsing + fresh water jetting)→1# hot air dryer→ annealing furnace →galvanizing→movable air cooler+air cooling1～5→water quenching →2# hot air dryer →skin pass →3# hot air dryer→tension leveler→ anti- passivation→ exit looper → inspection →shear→ recoiler→ coil unloading→ packing
1.3.2 Specification
Line style | Continuous Hot Dip GI&GL Line |
Material | CQ,DQ,DDQ |
Yield strength | σs≥710 MPa |
thickness | 0.3∼1.25mm |
Strip width | 700～1250 mm |
Coil inner diameter | Φ508/Φ610mm |
Coil weight | Max.25t |
Coil outside diameter | Φ850mm～Φ2100mm |
Product output:
Standard Refer to | JIS standard |
Products grade | CQ，DQ,DDQ |
Coil inner diameter： | Φ508/Φ610 mm |
Coil weight | Max. 25t |
Coil outer diameter | Φ850mm～Φ2100mm |
Coating status:
Spangle | Zero/Minimised/Medium/Large spangle SPM spangle |
Coating weight | GI: 60-400g/m2 (Both Side) GL:30-200g/m²(Both Side) |
Post treatment:
Skin passing, tension leveler, passivation,antifinger coating,oiling
Line speed:
Entry & exit section | 0～150m/min; |
Process section | Max.120m/min |
Threading speed | 20 m/min |
Line Length | 235m |
Crane hook level (tentative, only for reference)
Entry section | 11m |
Cooling tower | 33.5m |
Exit section | 11m |
1.3.3 Main equipment parameters
Welder
Type | Resistance welder (FMY150-C type) |
Welding capacity | Min 0.3+0.3mm, Max. 1.25+1.25mm |
Welding strip width | 700～1250mm |
Max. welding time | Max. 50s |
Looper
Annealing Furnace
Type | Horizontal-type, RTF Furnace |
Energy | NG |
TV value | 72 |
Output | Max. 37.3ton/hr for CQ |
Zinc pot
Pot type | Induction heating ceramics pot |
Arrangement | 2-pot 3-position + premelt pot |
GI pot capacity | 160ton |
GI pot inductor | 400Kw x 2sets |
GL pot capacity | 90ton |
GL pot inductor | 400Kw x 4sets |
Pre-melt pot capacity | 18ton |
Pre-melt pot inductor | 400Kw x 2sets |
Skin Pass Mill
Type | 4-Hiigh |
Rolling force | Max. 650ton |
Driving | Backup roll AC VVVF motor driven |
Elongation | Max.2.0% |
Tension leveler
Type | 2 bending and 2 straightening |
Elongation | Max.2.0% for CQ |
Finished strip shape | 3 I |
Driving system
SIEMENS conversion Control system for main driving
CPC、 EPC
1.4 Productivity Chart
1.4.1 Time schedule
Description | Days | Hours | Total |
Calendar time | 365 | 24 | 8760 |
Non-operation time |
|
| 1128 |
Annual maintenance | 22 | 24 | 528 |
Periodic maintenance | 25 | 24 | 600 |
Holidays | 17 | 24 | 408 |
Workable time |
|
| 7224 |
1.4.2 Production chart
CGL-CQ | |||||||
Sr.No. | Specification | Speed | Output | h/a | |||
THK(mm) | WDT(mm) | mpm | t/h | t/a | % | ||
1 | 0.3 | 914 | 120 | 15.5 | 1260 | 1.00% | 81 |
2 | 0.3 | 1100 | 120 | 18.7 | 3780 | 3.00% | 203 |
3 | 0.3 | 1250 | 120 | 21.2 | 5040 | 4.00% | 238 |
4 | 0.35 | 914 | 120 | 18.1 | 1260 | 1.00% | 70 |
5 | 0.35 | 1100 | 120 | 21.8 | 2520 | 2.00% | 116 |
6 | 0.35 | 1250 | 120 | 24.7 | 5040 | 4.00% | 204 |
7 | 0.4 | 1100 | 120 | 24.9 | 2520 | 2.00% | 101 |
8 | 0.4 | 1250 | 120 | 28.3 | 3780 | 3.00% | 134 |
9 | 0.45 | 1100 | 120 | 28.0 | 2520 | 2.00% | 90 |
10 | 0.45 | 1250 | 120 | 31.8 | 7560 | 6.00% | 238 |
11 | 0.5 | 1100 | 120 | 31.1 | 2520 | 2.00% | 81 |
12 | 0.5 | 1250 | 120 | 35.3 | 5040 | 4.00% | 143 |
13 | 0.6 | 1100 | 120 | 37.3 | 15120 | 12.00% | 405 |
14 | 0.6 | 1250 | 106 | 37.3 | 2520 | 2.00% | 68 |
15 | 0.7 | 1100 | 103 | 37.3 | 2520 | 2.00% | 68 |
16 | 0.7 | 1250 | 91 | 37.3 | 3780 | 3.00% | 101 |
17 | 0.8 | 1100 | 90 | 37.3 | 2520 | 2.00% | 68 |
18 | 0.8 | 1250 | 79 | 37.3 | 7560 | 6.00% | 203 |
19 | 0.9 | 1100 | 80 | 37.3 | 2520 | 2.00% | 68 |
20 | 0.9 | 1250 | 70 | 37.3 | 7560 | 6.00% | 203 |
21 | 1 | 1100 | 72 | 37.3 | 2520 | 2.00% | 68 |
22 | 1 | 1250 | 63 | 37.3 | 7560 | 6.00% | 203 |
23 | 1.2 | 1100 | 60 | 37.3 | 2520 | 2.00% | 68 |
24 | 1.2 | 1250 | 53 | 37.3 | 12600 | 10.00% | 338 |
25 | 1.25 | 1100 | 58 | 37.3 | 3780 | 3.00% | 101 |
26 | 1.25 | 1250 | 51 | 37.3 | 10080 | 8.00% | 270 |
Total | 126000 | 100.00% | 3556 | ||||
Total working hour is 6835 hours.
Output: Max. 37.3ton/hour for CQ
1.5 Utilities
Compressed Air
Water contents | ﹤ 1.3g/m3 |
oil contents | ﹤ 5ppm |
Temperature | Max. 32℃ |
Working pressure | 0.4 to 0.6Mpa |
Circulation Cooling Water
Total hardness (Ca+Mg) | ≤16dh |
PH value | 6 to 8 |
Suspension | Max.20mg/L |
Temperature | Max.33℃ |
Pressure | 0.4 to 0.6MPa |
Demi Water
Electro conductibility | ≤10μs/cm |
PH value | 6.5 to 7 |
Hardness | ≤0.03mmol/L |
Oil content | ≤2mmol/L |
Suspension | ≤5mg/L |
Total pressure | 0.5 to 0.6MPa |
Sewage Discharge
Alkali, oil contained | PH=9 to 13 |
Pressure | P=0.3 MPa |
Flux | 3 t/h |
H2、 N2 provided by protective gas station
Purity | ≥99.99% |
Oxygen content | ≤5ppm |
Dew-point | D.P.≤-65℃ (1 atm) |
Nitrogen pressure | 0.05 to 0.5MPa(adjustable) |
Flow rate | Max. 600 Nm3/h (Including sealing N2) |
Liquid nitrogen tank capacity | 10m3 (for reference) |
Natural Gas
Calorific Value | 8500 kcal/Nm3 |
Flow rate | 800 to 1200 Nm3/hr |
Pressure | 80±10% mbar (at burner input flange) |
Consumption | about 24 Nm3/mt (Only for furnace) |
Electric power supply
Low voltage | 380V, AC±10％, 3 phases |
Auxiliary | 220V, AC±10％, single phase |
Electrical connected load | about 7000kW |
Running load | Max.3000kVA |
Consumption
Sr.No. | Utility | Peak flow | Average flow | Consumption |
1. | Compressed air | 900 m3/hr | 700 m3/hr | 15 m3/ton |
2. | Circulating cooling water | 600 m3/hr | 400 m3/hr | – |
3. | Demi water | 6 m3/hr | 6 m3/hr | 0.2 m3/ton |
4. | H2 | 180 Nm3/h | 160 Nm3/h | 4 Nm3/ton |
5. | N2 | 600 Nm3/h | 500 Nm3/h | 10 Nm3/ton |
6. | Emergency N2 | 800 Nm3/h | 500 Nm3/h | 500 Nm3/h × 4hours |
7. | NG | 1200Nm3/hr | 500 Nm3/hr | 24 Nm3/mt (only for furnace @ reference strip 0.3×1220mm× 150mpm)
|
8. | Electric | 7000kW | 3000kW | For drive:50 kWh/ton for GI For electric heating (pot + furnace): 20kWh/ton
|
1.6 Roll List
Equipment | Roll | Material | SIZE (mm) | Coating | Coating THK |
Bridle roll | Before coating | 16Mn | Ф650×1600 | Cr plated | 50-70μm |
After coating | 16Mn | Ф650×1600 | Cr plated | 50-70μm | |
Snubber roll | 20# | Ф200×1600 | NBR lined | 15mm | |
20# | Ф200×650 | NBR lined | 15mm | ||
Steering roll | Steering roll | 16Mn | Ф600×1600 | Cr plated | 50-70μm |
Skin Pass Mill | Work Roll | Cr5 | Ф370-400×1580 | Surface hardening | 30～ 40μm |
Back Up Roll | Cr3 | Ф670-700×1650 | Surface hardening | 30～ 40μm | |
TLL Levelling units | Work roll | GCr15 | Ф20×1550 | Cr plated | – |
Intermediate roll | Ф35×1550 | Cr plated | |||
Back up roll | Ф65×132×3 | Surface hardening | |||
TLL anti-cross bow unit | Work roll | GCr15 | Ф50×1550 | Cr plated | – |
Intermediate roll | Ф35×1550 | Cr plated | – | ||
Back up roll | Ф65×132×3 | Surface hardening | – | ||
TLL anti-crimp unit | Work roll | GCr15 | Ф70×1550 | Cr plated | – |
Intermediate roll | Ф35×1550 | Cr plated | – | ||
Back up roll | Ф65×132×3 | Surface hardening | – | ||
Entry Looper | Deflector roll | 16Mn | Ф600×1600 | Cr plated | 50-70μm |
Exit looper | Deflector roll | 16Mn | Ф600×1600 | Cr plated | 50-70μm |
Squeeze roll | Squeeze roll | 20# | Ф200×1600 | NBR lined | 15mm |
Brush roll | Brush roll | 35# | Ф300×1600 | – | – |
Back up roll | 16Mn | Ф200×1600 | Cr plated | 50-70μm | |
Furnace | Hearth roll | heat-resisting steel | Ф150×1600 | – | – |
Hot bridle roll | heat-resisting steel | Ф650×1600 | – | – | |
Deflector roll on CAG | Deflector roll | 16Mn | Ф1000×1600 | Cr plated | 50-70μm |
Snubber roll | Q345B | Ф250×1600 | Cr plated | 50-70μm | |
Water quenching | Sink roll | 20# | Ф800×1600 | Cr plated | – |
Coater | Applicator roll | 20# | Ф320×1550 | PU lined | 25mm |
Pickup roll | 20# | Ф320×1550 | Cr plated | – | |
Pinch Roll | Pinch roll | 20# | Ф200×1600 | NBR lined | 15mm |
flector roll | 16Mn | Ф350×1600 | Cr plated | 50-70μm | |
Support roll | Support roll | 20# | Ф100×1600 | NBR lined | 15mm |
1.7 Motor List (for reference)
No. | Equipment | Power（kw） | Voltage（V） | Speed(m/min） | Pole |
1 | No.1 Pay off reel | 45 | 380 | 30/150 | 8:00 PM |
2 | No.2 Pay off reel | 45 | 380 | 30/150 | 8:00 PM |
3 | No.1 Bridle Roll | 30 | 380 | 30/120 | 6:00 PM |
22 | 380 | 30/120 | |||
18.5 | 380 | 30/120 | |||
4 | Entry Looper | 55 | 380 | 30/220 | 6:00 PM |
5 | No.2 Bridle Roll | 15 | 380 | 30/120 | 6:00 PM |
18.5 | 380 | 30/120 | |||
6 | No.3 Bridle Roll | 37 | 380 | 30/120 | 6:00 PM |
22 | 380 | 30/120 | |||
18.5 | 380 | 30/120 | |||
7 | Hot Bridle Roll | 15 | 380 | 30/120 | 6:00 PM |
18.5 | 380 | 30/120 | |||
8 | No.4 Bridle Roll | 22 | 380 | 30/120 | 6:00 PM |
30 | 380 | 30/120 | |||
45 | 380 | 30/120 | |||
55 | 380 | 30/120 | |||
9 | No.5 Bridle Roll | 45 | 380 | 30/120 | 6:00 PM |
55 | 380 | 30/120 | |||
10 | Skin Pass Mill | 55×2 | 380 | 30/120 | 6:00 PM |
11 | Tension Leveler | 380 | 30/120 |
|
|
12 | No.6 Bridle Roll | 90 | 380 | 30/120 | 6:00 PM |
75 | 380 | 30/120 | |||
45 | 380 | 30/120 | |||
30 | 380 | 30/120 | |||
13 | Pick up roll of Coater | 15 | 380 | 30/120 | 4:00 PM |
14 | Applicator roll of Coater | 18.5 | 380 | 30/120 | 4:00 PM |
15 | Exit Looper | 25 | 380 | 30/120 | 6:00 PM |
16 | No.7 Bridle Roll | 30 | 380 | 30/150 | 6:00 PM |
37 | 380 | 30/150 | |||
17 | Tension Reel | 185 | 380 | 30/150 | 8:00 PM |
