Entry and welding
Uncoiling and welding establish a stable strip feed into the continuous sections.
Direct Rolling Annealing and Pickling
DRAP line for shorter stainless steel hot strip processing.
DRAP combines direct rolling, annealing, pickling and finishing functions to reduce process steps and improve productivity for selected stainless steel hot strip programs.
Overview
For plants that want annealing, pickling and online reduction in one route.
The workbook positions DRAP and DRAPL as short-route stainless steel processing lines that can combine hot coil pickling, annealing, online rolling and finishing sections.
- Applicable to 200, 300 and 400 series hot rolled stainless steel coil in benchmark data.
- Can integrate Z-Hi or other online rolling technology depending on product plan.
- Best reviewed when throughput, gauge reduction and surface quality are evaluated together.
Process Route
Short-route integration changes the whole line balance.
DRAP is more than a pickling section. It must balance rolling load, furnace duty, acid cleaning and downstream strip handling.
Pickling and annealing
Scale removal and thermal treatment are matched to the hot strip condition.
Online rolling
Z-Hi or other rolling units can reduce gauge and shorten the process route.
Final pickling or finishing
Finishing sections stabilize surface quality and coil output.
Parameters
DRAP data extracted from domestic benchmark cases.
These values help define early feasibility before a complete project configuration.
| Item | Workbook Data | Engineering Note |
|---|---|---|
| Typical use | Hot strip pickling with online rolling, annealing and finishing | Shortens process route compared with separate lines |
| Capacity samples | 350,000-370,000 t/a or 60 tph samples | Benchmark cases vary by line configuration |
| TV value | 100 in selected samples | Use for comparison with HAPL routes |
| Main process | Uncoiling, welding, pickling or annealing, online rolling, pickling or skin-pass | Final order depends on technology package |
| Key decision | Online rolling scope and finishing target | Controls investment, output and product mix |
Line Value
Higher process density with fewer standalone steps.
JINYE reviews DRAP feasibility through material route, gauge reduction target, line speed and site utilities.
Short route
Combines multiple processes to reduce intermediate handling.
Productivity
Continuous layout improves line utilization when the product mix fits.
Online control
Rolling, tension and acid process settings can be reviewed as one production system.
Project screening
Early coil data helps decide whether DRAP or HAPL is the better fit.