For Henan Jinyubang Industrial Co., Ltd.'s continuous annealing and pickling line, Suneng participated in equipment supply for the annealing furnace and solution-treatment cooling section. Compare similar strip projects by first matching actual width, thickness and temperature progression, then reviewing heating, cooling, drying and whole-line interfaces separately. Drawing on the 2017 technical annex and published project records, this page explains that assessment. Proposal parameters are not actual output or acceptance results.
Compare actual strip, not only the “850 mm line” designation
The technical annex calls the project an “850 mm hot-rolled stainless-steel continuous annealing and passivation line” and specifies continuous annealing and solution treatment of stainless-steel strip. Existing project information uses “continuous annealing and pickling line”, retained here. This discussion is limited to the annealing furnace and solution-treatment cooling/drying equipment. It does not include pickling, passivation or other whole-line equipment in Suneng's supply scope.
850 mm is the nominal line size. The design material range is 200/300-series stainless steel, 480–750 mm wide and 1.6–4.0 mm thick. Compare the new project's grades, usual sizes and maximum width/thickness first. If within that range, proceed to temperature and speed comparisons. If outside, reassess effective passages, supports and heat-treatment capability rather than reusing the nominal size. The difference between nominal size and actual strip width cannot be assumed to be tracking or edge allowance.
| Parameter | Condition in the 2017 technical annex |
|---|---|
| Nominal line size | 850 mm; not actual strip width |
| Proposed strip width | 480–750 mm; 200/300-series stainless steel |
| Proposed thickness | 1.6–4.0 mm; compare with specific grade and width |
| Strip annealing temperature | 1050–1150°C; the proposal's strip-temperature range |
| High-temperature furnace-section design limit | 1300°C; not the target strip temperature |
| Proposed heating-furnace length | Approximately 130 m, excluding cooling and other sections: 40 m preheating, 36 m rapid heating, 54 m soaking |
| Separately listed solution-cooling and drying section | Approximately 45 m overall, including combined cooling, squeeze drying and hot-air drying |
| Speed calculation | TV = strip speed (m/min) × thickness (mm); design TV approximately 190 m·mm/min, distinct from acceptance and maximum-speed bases |
Parameter source: “Design Basis” and “Process Overview” in the Technical Annex for Annealing Furnace and Solution-Section Equipment of an 850 mm Hot-Rolled Stainless-Steel Continuous Annealing and Passivation Line, dated 26 July 2017. These values compare this project's proposed conditions; they are not capability guarantees for a new project.
Connect heating, cooling and drying into one temperature progression
Temperature progression means how the strip heats, holds and cools through successive sections. The annex divides the approximately 130 m heating furnace into preheating, rapid heating and soaking, then separately lists approximately 45 m of solution cooling and drying. When comparing layout and supplied lengths, mark furnace entry and exit, cooling exit, dryer exit and upstream/downstream handover points. The 130 m figure is not the whole system footprint, and adding approximate lengths does not replace a general arrangement drawing.
The annex explains annealing/solution treatment as removing work hardening, dissolving carbides into the microstructure and retaining the required structure through subsequent cooling. It also states that cooling rate and uniformity affect properties and strip shape. Sensitisation means that certain thermal histories can cause precipitates in some stainless steels to deplete chromium near grain boundaries, increasing susceptibility to intergranular corrosion. This general mechanism explains why heating and cooling need review; it does not justify one sensitisation temperature range for all 200/300-series materials. Grade, incoming condition and product requirements remain the starting point. Mechanism reference: Outokumpu on stainless-steel corrosion resistance.
The proposed sequence is air cooling, water-mist cooling and water cooling, followed by squeeze drying and hot-air drying. The sections address more than sensitisation: they also affect cooling uniformity, strip shape, residual surface water and downstream strip handover. Water cooling is not the final temperature stage. The annex specifically notes that drying air may reheat the strip at low speed, so check final strip temperature after drying as well as the water-cooling outlet.
The retained annex's process overview, equipment descriptions and assessment table use different definitions for some cooling-outlet temperatures. This page selects none as a common promise. For a new project, put each section temperature together with material, thickness, speed, measurement location and applicable clause in one process table. If dryer-exit or downstream allowable temperatures conflict, reconcile handover requirements before selecting cooling, drying and final cooling equipment.
What does TV compare, and what can it not guarantee?
The annex defines TV as speed multiplied by thickness and gives a design value of approximately 190. It separately specifies acceptance speed, maximum speed and representative sizes. These are not interchangeable indicators. Later clauses also give differing representative widths; use a jointly confirmed revision and operating-condition table.
For a similar project, select one material, width, thickness and target strip temperature first, then check whether required speed and heating, soaking and cooling times can all be matched. Assuming a TV value applies, dividing it by thickness gives only a calculated speed under that assumption. It does not establish mechanical maximum speed, actual output or acceptance at that thickness. Faster requirements call for reassessment of section treatment times, cooling and whole-line speed constraints. The 54 m soaking section's length alone does not establish that it is the production bottleneck.
Define Suneng's section and the whole-line handover
Suneng is the annealing-furnace and solution-cooling-section equipment supplier in this project, working with the engineering buyer. Published project records support its equipment contribution in furnace body, cooling section, combustion and controls, and cooperation with installation and commissioning. Specific responsibilities depend on the relevant documents. General company capabilities must not all be described as work completed in this project.
The annex's “Equipment Supply Scope” and “Supply Responsibility Allocation” list the annealing-furnace body, online disc-roll changing system, solution-cooling section, chimney, furnace-side pipework and electrical controls, separating design, manufacture, installation, commissioning and supply responsibilities. This makes system integration specific to equipment items. A new project can list who designs, supplies, installs and validates each item. Proposed assignments do not constitute completion records.
Check electrical equipment, site secondary cables and trays, and drive control synchronised with the main line separately. Technical functions, hardware supply and site wiring are different responsibilities. A listed function is not automatically included in every quotation. Foundations and embedded parts, the buyer's incoming electrical supply, and water/gas connection points also need separate allocation before coordination with the whole-line contractor.
The annex uses natural-gas heating and lists fuel-gas-pressure and combustion-air-pressure protection and an exhaust system. Utilities distinguish clean circulating water, dirty circulating water and emergency supply for different furnace-roll and strip-cooling duties. The annex also lists these safety provisions: automatic burner ignition with flame detection, flame-failure protection and alarms; an emergency quick-shut-off valve and venting devices on the natural-gas pipework, with all fuel-gas pipes purged with nitrogen before operation; a rupture disc at the end of the combustion-air main; and an emergency power supply of about 55 kW that keeps the disc rolls and support rolls turning and powers the controls during a power loss. When comparing similar projects, confirm item by item who supplies each device and who commissions and verifies it. This section is heated directly by natural-gas burners; scale on the strip is removed in the downstream pickling process, so it is not bright annealing under a hydrogen-bearing protective atmosphere. Pickling and its acid-fume treatment are also outside this section's supply scope. Check who brings each utility to its connection, how furnace exhaust joins the site system, and how furnace and main line exchange signals and confirm interlocks during strip stoppage, power loss or water loss. The annex contains some alarms and emergency arrangements, but this page does not derive a complete operating sequence or claim validation of all abnormal conditions.
Information needed before quotation
Provide the available material-grade and width/thickness schedule, required strip speed, annealing/solution-treatment and cooling requirements. Add a layout marking section handovers and proposed supply responsibilities. If information is incomplete, begin with what is known.
Initial review has two steps: establish comparability of material and temperature progression, then align heating-furnace, cooling/drying and site-interface scope. Different specifications or temperature requirements require process and equipment-capability calculations. Similar conditions with different supply lists require clarified handover responsibilities before configuration and price comparison. This avoids assuming transferability from “850 mm” or “130 m total length” alone.