Spraying System ဖြင့် Coating Pan

What is a Coating Pan with Spraying System?

တစ် coating pan with spraying system (commonly called a film coater or pan coater) is an industrial machine used to apply liquid coatings — aqueous or organic film, sugar coatings, colours, or specialised functional layers — onto solid units such as tablets, pellets, candies or food pieces. The system integrates a rotating coating pan (non-perforated or perforated) with a metered spraying subsystem and controlled hot-air drying to form uniform, repeatable coatings. :contentReference[oaicite:0]{index=0}

Core Components

• Coating Pan / Drum — circular metal pan mounted at a tilt; diameters commonly range from bench-top lab sizes (≈150–400 mm) to production pans (several hundred millimetres to >1000 mm). The pan provides the tumbling motion that exposes all surfaces of the product to the spray. :contentReference[oaicite:1]{index=1}
• Spraying System — pump (peristaltic or precision metering pump), supply tank, piping, and atomising spray nozzles (air-atomising or two-fluid nozzles). Nozzles atomize the coating solution into fine droplets for even deposition. :contentReference[oaicite:2]{index=2}
• Air / Drying System — blower/fan, heater (electric or steam), air distribution (immersion sword/tube, baffled pan, or diffuser), and exhaust with filtration or solvent recovery where needed. :contentReference[oaicite:3]{index=3}
• Control & Instrumentation — variable pan speed control, spray rate adjustment, temperature and air-flow monitoring, and often touchscreen PLC control for recipe storage and repeatability. :contentReference[oaicite:4]{index=4}

How It Works — Step-by-Step

1. Load — tablets/pellets are fed into the pan.
2. Tumble — pan rotation creates a rolling bed so all unit surfaces are exposed. Typical pan speeds vary by size and product (e.g., 4–30 rpm depending on process). :contentReference[oaicite:5]{index=5}
3. Spray — the spraying system meters the coating solution to one or more nozzles which atomize the liquid and apply a fine mist to the tumbling bed. Spray rate and droplet size are tuned to the formulation and bed temperature. Typical spray rates for production coaters range broadly (order of tens to a few hundreds ml/min per gun depending on formulation and pan size). :contentReference[oaicite:6]{index=6}
4. Dry — heated air (inlet air typically 40–80°C for aqueous film coating) removes solvent/moisture and fixes the film. Air volume and temperature must match spray rate to avoid over-wetting or rough surfaces. :contentReference[oaicite:7]{index=7}
5. Unload — when desired coating weight and appearance are achieved, the coated units are discharged and collected.

Key Technical / Typical Parameters (reference ranges)

• Pan diameter (lab → production): ~150 mm – >1000 mm. :contentReference[oaicite:8]{index=8}
• Pan speed: ~4 – 30 rpm (process dependent). :contentReference[oaicite:9]{index=9}
• Inlet air temperature: 40 – 80 °C (aqueous coatings typical). :contentReference[oaicite:10]{index=10}
• Air volume (fan): ~200 – 1000 m³/h (lab → production ranges). :contentReference[oaicite:11]{index=11}
• Spray rate (per nozzle / per gun): commonly ~50 – 225 ml/min for many production aqueous coatings (some nozzle datasheets and applications cite typical nozzle flow 50–150 ml/min or 6–30 L/h depending on model). For very fine/controlled spray the range can be lower (single-digit ml/min) on lab coaters. :contentReference[oaicite:12]{index=12}
• Nozzle types: air-atomising two-fluid nozzles (good droplet control), internal/external mix designs; typical liquid orifice sizes 0.8–1.8 mm (model dependent). :contentReference[oaicite:13]{index=13}
• Spray pump: peristaltic or gear metering pumps are common for stable, pulsation-controlled flow. :contentReference[oaicite:14]{index=14}

Spraying System Details & Best Practices

• Nozzle selection: choose atomising type (air-assisted) when you need smaller droplets and better surface finish; hydraulic nozzles are simpler but produce larger droplets. Match nozzle orifice and atomising air pressure to solution viscosity and desired droplet size. :contentReference[oaicite:15]{index=15}
• Spray rate vs. drying capacity: maintain a balance — increase spray slowly while verifying bed temperature; too high a spray relative to air capacity causes over-wetting, agglomeration or rough coatings. Scale-up studies repeatedly show that spray rate, pan speed and air flow must be co-optimized. :contentReference[oaicite:16]{index=16}
• Multiple guns: large pans often use multiple spray guns spaced for even coverage; monitor individual gun flows for consistency. :contentReference[oaicite:17]{index=17}
• Cleaning & CIP: non-perforated pans are usually easier to clean, but fixed spraying systems need accessible piping/nozzle removal for CIP when switching products or colours. Validation protocols often specify flows and temperatures for cleaning cycles. :contentReference[oaicite:18]{index=18}

Typical Applications

• ဆေးဝါးများ film coating (taste masking, enteric coatings, controlled release), sugar coating. :contentReference[oaicite:19]{index=19}
• Food / Confectionery: chocolate/sugar panning, nut coatings, vitamin tablets. :contentReference[oaicite:20]{index=20}
• Nutraceuticals & Supplements: capsule/pellet coatings for stability and swallowability. :contentReference[oaicite:21]{index=21}

Example Model Table (illustrative)

Selection Guide — How to Choose the Right Coating Pan with Spraying System

1. Define product & formulation

• Unit size/shape, fragility, porosity and coating formulation (solid content, viscosity, solvent system) determine required spray droplet size, spray rate and pan motion. :contentReference[oaicite:23]{index=23}

1. Match spray capacity to drying

• Calculate target spray rate (ml/min) from desired coating weight gain and batch mass; ensure the dryer (air volume & temperature) can remove evaporated solvent without overheating the bed. Scale-up literature emphasises maintaining similar spray/air ratios across scales. :contentReference[oaicite:24]{index=24}

1. Choose nozzle & pump combination

• For fine, smooth films use air-atomising two-fluid nozzles with peristaltic or precision metering pumps; select nozzle orifice and atomising air pressure by solution viscosity. :contentReference[oaicite:25]{index=25}

1. Consider production vs. flexibility

• Perforated pans (with through-flow air) dry faster and suit high throughput; standard (non-perforated) pans are simpler and cheaper for small batches or confectionery. :contentReference[oaicite:26]{index=26}

1. Hygiene & validation needs

• For pharma/nutraceuticals verify GMP compatibility, material choice (SS316, polished surfaces), and availability of IQ/OQ/PQ & CIP procedures. :contentReference[oaicite:27]{index=27}

Troubleshooting — Common Coating Defects & Causes

• Streaks / uneven coating: uneven spray pattern, nozzle blockage, or poor gun spacing.
• Blisters / peeling: too high inlet air temperature or solvents evaporating too quickly.
• Agglomeration / sticking: spray rate exceeds drying capacity or poor pan speed/feed balance.
• Orange peel / rough surface: excessively small droplets or too rapid drying.
  (These correlations are widely reported in pan-coating literature and manufacturer application notes.) :contentReference[oaicite:28]{index=28}

Summary

A coating pan with an integrated spraying system is a proven, flexible solution for producing uniform coatings on tablets, pellets and confectionery items. Proper selection and tuning of pan geometry & speed, spray rate & nozzle type, and air/drying capacity are critical to process success. For scale-up and routine operation, maintain a careful balance between spray input and drying