2026-07-09 | 10 Most Common Questions · 25 Years of Field Experience | Author: Lanxing Qingxi — Luo Huiyong
Over 25 years in the industrial equipment cleaning industry, we receive countless inquiries daily from plant managers, maintenance engineers, and procurement professionals. The questions are remarkably consistent — from "Does my equipment need cleaning?" to "What does it cost?" and from "Will cleaning damage my equipment?" to "How often should it be done?" This article consolidates the 10 most frequently asked questions, answered with the practical expertise accumulated by Lanxing Qingxi through decades of field operations.
We offer three core processes — chemical cleaning, high-pressure water jetting, and organic solvent cleaning — covering virtually all industrial equipment involving heat exchange, fluid transport, or chemical reaction:
We select single or combined processes based on deposit type (scale, rust, oil sludge, carbon deposits, silicate scale, biofilm, etc.), strictly following China's HG/T 2387-2007 national standard, with post-cleaning passivation treatment. Lanxing Qingxi — 25 years of industrial cleaning expertise. Free on-site inspection. Call +86 18952832843.
Evaluate across four dimensions — any two indicators suggest it's time to clean:
Delaying cleaning has serious consequences: a mere 0.5 mm scale layer reduces heat transfer efficiency by 8–12%. The thicker the scale, the harder and more expensive it is to remove — and the higher the risk of under-deposit corrosion and perforation. Lanxing Qingxi provides free on-site inspection to accurately assess your equipment's condition.
There is no fixed price — costs depend on equipment type, size, deposit thickness, cleaning method, and site conditions. Approximate ranges per single cleaning event:
| Equipment Type | Approx. Cost (CNY) | Key Price Drivers |
|---|---|---|
| Heat exchanger (per unit) | 3,000–20,000 | Surface area, tube pass count, scale thickness |
| Steam boiler | 8,000–50,000 | Evaporation capacity, scale thickness, boiler type |
| Power plant condenser | 20,000–80,000 | Unit capacity, tube count |
| Reactor | 5,000–30,000 | Volume, material, deposit composition |
| HVAC system | 5,000–30,000 | Number of chillers, cooling tower specs |
Cost breakdown: chemicals 30–45%, labor 25–35%, equipment 10–15%, waste treatment 5–10%. Always get quotes from 3+ providers, but never choose on price alone — low bids often mean skipped inhibitors or untreated waste discharge. Lanxing Qingxi inspects first, quotes second — all quotes itemized with VAT, no hidden fees.
This is the #1 concern — the answer: when performed professionally, chemical cleaning is perfectly safe.
Modern inhibitor technology keeps corrosion rates well within China's national standard GB/T 25146-2010:
| Material | Standard Limit | Lanxing Actual | Typical Inhibitor |
|---|---|---|---|
| Copper alloys | ≤1.0 g/(m²·h) | 0.2–0.5 | BTA (Benzotriazole) |
| Carbon steel | ≤2.0 g/(m²·h) | 0.3–0.8 | Urotropine + Sodium Molybdate |
| Stainless steel | ≤1.0 g/(m²·h) | 0.1–0.3 | Sodium Molybdate (anodic passivation) |
Our safety measures: ① custom inhibitor formulation matched to equipment metallurgy; ② real-time corrosion coupon monitoring throughout the process; ③ strict control of temperature, flow velocity, and contact time; ④ post-cleaning passivation to form a protective oxide film. The real danger is unprofessional cleaning — no inhibitors, uncontrolled temperatures, one-size-fits-all acid. Lanxing Qingxi: zero equipment damage incidents in 25 years.
These are complementary methods, not competitors. Selection is deposit-driven, and the best results come from combining both:
| Dimension | Chemical Cleaning | HP Water Jetting |
|---|---|---|
| Target deposits | Scale, rust, oil sludge, silicate scale | Loose debris, polymer deposits, hard blockages |
| Best applications | Tube-side interiors, non-removable equipment, complex flow paths | Shell-side exteriors, removable bundles, large surface areas |
| Cleaning depth | All liquid-wetted surfaces, microscopic scale removal | Line-of-sight limited; tube bundle centers may be missed |
| Substrate impact | Requires inhibitors; minor corrosion risk if mismanaged | Purely physical; no chemical corrosion |
| Environmental | Generates liquid waste requiring treatment | Rinse water only; relatively eco-friendly |
| Recommended combo | HP water first to strip bulk deposits → chemical circulation to dissolve hard scale. Highest efficiency. | |
In practice, Lanxing Qingxi deploys combined processes on most projects: HP water (500–1,500 bar) rapidly clears shell-side and tube-sheet deposits, followed by chemical circulation to dissolve hard scale deep inside tube interiors. We provide a free customized plan after on-site inspection — no forced single-method recommendation.
Duration depends on equipment size and fouling severity:
| Scale | Typical Duration | Examples |
|---|---|---|
| Small | 1–2 days | Single heat exchanger, small condenser, cooling tower |
| Medium | 3–5 days | HVAC system, multiple heat exchangers, small boiler |
| Large | 7–14 days | Power plant condenser, large boiler, tank farm |
Actual duration is also affected by deposit thickness, equipment accessibility, and onsite utility conditions. We provide a day-by-day schedule with milestones after inspection. During execution, we use parallel operations and cross-deployment to compress the timeline and minimize production downtime. Emergency jobs can be expedited — 24-hour response.
After cleaning, equipment typically operates well for 1–2 years, depending on water quality, operating temperature, and duty cycle:
| Equipment Type | Recommended Interval | Key Indicators |
|---|---|---|
| Shell-and-tube / plate heat exchangers | 6–18 months | ΔT change, ΔP increase |
| Steam boilers | 1–3 years | Boiler water quality, scale thickness |
| Condensers | 6–12 months | Vacuum level, terminal temperature difference |
| HVAC chillers | 12–24 months | Approach temperature |
| RO membranes | 3–6 months | Permeate flow drops 10–15% |
Maintenance tips: ① Dose water treatment chemicals regularly (scale/corrosion inhibitors, biocides); ② Maintain an operating parameter log — investigate any deviation >10% from baseline; ③ Perform borescope inspections during outages to assess scale growth. Lanxing Qingxi can help develop a full-lifecycle maintenance plan and long-term service agreement.
Fully compliant. Chemical cleaning wastewater is treated strictly per GB/T 31188-2014 and GB 8978-1996 national standards:
For environmentally sensitive sites, Lanxing Qingxi recommends a physical-cleaning-first, chemical-passivation-supplement approach — using 3D rotating HP spray heads plus closed-loop circulation passivation, reducing wastewater volume by over 98% compared to traditional full-tank chemical cleaning. We can provide wastewater test reports for environmental compliance audits. Always verify a provider has a clear waste treatment plan and compliant disposal channels — this is the key differentiator between professionals and amateurs.
Evaluate across five dimensions to avoid costly mistakes:
Lanxing Qingxi has followed a disciplined "sample first → custom plan → execute → verify" process for 25 years, delivering complete before-and-after data and written acceptance reports on every project. Service coverage: Jiangsu (Nanjing, Suzhou, Wuxi, Changzhou, Zhenjiang, Yangzhou), Zhejiang (Hangzhou, Ningbo), Shanghai, Anhui (Hefei). Call +86 18952832843.
Chemical cleaning quality acceptance follows China's national standard GB/T 25146-2010:
| Acceptance Item | Pass Criteria | Test Method |
|---|---|---|
| Visual inspection | Surface clean, no residual scale or corrosion spots, uniform metallic appearance | Visual + photographic record |
| Residual scale thickness | ≥5 random measurement points, all ≤0.1 mm | Thickness gauge |
| Corrosion rate | Copper alloys ≤1.0 g/(m²·h), carbon steel ≤2.0 g/(m²·h) | Coupon weight-loss method |
| Operating parameter recovery | Heat transfer ΔT within ±5% of design, pressure drop deviation ≤10% | Before/after data comparison |
| Passivation film quality | Copper sulfate spot test: no copper precipitation within 30 s (stainless steel) | CuSO₄ spot test |
We recommend writing these acceptance criteria into the contract to avoid disputes. Lanxing Qingxi provides complete before-and-after comparison data and written acceptance reports for every project — so you have documented proof of quality.
📞 Phone: +86 18952832843 | Web: www.lanxingqingxi.com
Service Coverage: Jiangsu (Nanjing, Suzhou, Wuxi, Changzhou, Zhenjiang, Yangzhou) · Zhejiang (Hangzhou, Ningbo) · Shanghai · Anhui (Hefei)
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