Editorial Technical Reference

Automated pharmaceutical tablet coating system: recipe control, closed handling, wash-in-place and in-line thickness monitoring

Production film coater with recipe control, closed loading and discharge, automatic washing and in-line coating-thickness sensing

An automated pharmaceutical tablet coating system is a production drum coater built so that a recipe, not an operator, runs charging, spraying, drying, discharge and cleaning, with process data recorded for each batch and, increasingly, the coat measured in-line while it grows. Ask three things first: which steps run automatically with the door closed, what the control system records and how it complies with electronic-record rules, and how coat thickness or end point is measured during the run.

Production-scale automated film coaters for tablets, judged on their control system, closed charging and discharge, automatic washing and in-line process measurement. Sizing the pan charge, drying air and spray rate, and the mixing mechanics of drum and baffles, are covered on the Pharmaceutical tablet coating machine (pan coater) page. Fluid-bed coaters, laboratory coaters, coating formulations and battery or thin-film coaters are outside this page.

CNFX editorial research · Sources checked October 12, 2026 · 3 sources

Check what runs automatically Measure the coat in-line

Open door of a stainless perforated-drum tablet coater showing pink coated tablets and a spray-gun manifold inside, a touchscreen control panel beside it and a lined drum of coated tablets in front — Perforated drum coater with spray manifold and control panel

Start with your task

Check what runs automaticallyRecipe, loading, washing. Measure the coat in-lineTerahertz end point.

Check which steps run automatically and what the control records

ACG's SMARTCOATER 1400 X•ONE lists a working capacity of 140 to 1,400 L for tablet coating (the minimum for select formulations only), and 560 to 1,120 L for micro-tablets and 700 to 1,120 L for pellets, with flexibility to run 10–100% batch occupancy. ACG describes a modular, automated design for tablet charging and discharging with built-in discharge baffles, dust-free closed-door charging and 100% tablet discharge, and a command and control system it states is compliant with ATEX, GAMP 5 and 21 CFR Part 11. [1]

L.B. Bohle, describing its redesigned BFC coater, writes that a fill level between 10 and 100% corresponds to 65 to 650 L on a BFC 400. Its iFix control system records long-term measured values, alarms and messages, provides data interfaces to external systems and a recipe management system, and the nozzle angle and distance adjustment is motorised and automatic. [2]

Bohle also lists fully automatic sampling and loading of tablets with the door closed, discharge by reversing the drum and adjusting its inclination, followed by fully automatic cleaning, with an extra cleaning lance at the bottom of the unit as standard. [2] ACG describes wash-in-place with an arranged set of nozzles that wets dead spots, and a spray nozzle with an anti-bearding cap it says is 50% lighter. [1]

Editorial note: makers state compliance with 21 CFR Part 11 and GAMP 5 for their control systems; ask for the validation documents, audit-trail description and user roles, and for the washing recipe and its cleaning validation data, rather than the claim alone.

Give the supplier the tablet size, shape and core mass, batch volume range, coating system and solvent (aqueous or organic), which steps must run with the door closed, the control and data standards required (21 CFR Part 11, GAMP 5, ATEX), the plant data system interface, washing and drying requirements, and any in-line sensor to be fitted.

Measure coat thickness in-line to set the end point

Researchers at the University of Cambridge, the University of Liverpool and TeraView fitted an in-line terahertz sensor to the side of a production-scale, side-vented perforated pan coater (Premier 200) coating 175 kg batches of 10 mm, 370 mg biconvex tablets with three spray guns at 300 mL/min, 1.5 bar atomising air, 6 rpm, 2,200 m³/h inlet air at 52 °C and exhaust at 38–40 °C. [3]

The sensor acquired waveforms at 120 Hz; with strict selection, 8,200 tablet readings over 6 hours (about 0.3% of waveforms, over 20 tablets per minute) gave R² = 0.91 and RMSE = 5.8 µm against off-line terahertz measurements, and relaxed selection raised the readings to 16,660 at R² = 0.8 and RMSE = 10 µm. [3]

The study used the sensor to detect induced faults: removal of the baffles, uncoated cores added part way, the drum halted and spray guns blocked or slowed. Inter-tablet variability fell with time along a log–log slope of −0.57. [3] Editorial note: an in-line reading is only useful for an automated end point if the control system can act on it; ask how the sensor signal enters the recipe and what happens when readings drop out.

Automatic charging, sampling, discharge and washing differ by model

The supplier linked to this page lists tablet coating machines it describes as highly automated; the card links to the page reviewed.

Ask each supplier which steps of charging, sampling, discharge and washing are automatic on the model offered, what the control system records, and whether in-line sensors have been fitted to it.

What surrounds the perforated drum: spray arm, air handling, wash-in-place and controls

Part	Role	Fix in the order
Perforated drum	Holds and mixes the bed; one study used 3 mm holes with 51% open area. [3]	Volume range and fill level.
Spray arm and nozzles	Motorised angle and distance. [2] Anti-bearding cap. [1]	Nozzle count and adjustment.
Charging and discharge	Closed-door loading; discharge by reversing drum. [1] [2]	Automatic or manual.
Air handling	Inlet and exhaust conditions under recipe; heat recovery option. [3] [2]	Airflow, temperature, humidity.
Wash-in-place	Nozzles and bottom lance for automatic cleaning. [1] [2]	Washing recipe and drain.
Control system	Recipes, alarms, long-term data, interfaces. [2] Part 11, GAMP 5. [1]	Platform and validation pack.
In-line sensor	Terahertz coat thickness per tablet. [3]	Sensor type and port.

Spray rate, atomising air and inlet air: the coating-pan figures to pin down

Field	What it means and published values	Ask the supplier for
Batch capacity (kg)	Examples: 140–1,400 L working capacity; 65–650 L at 10–100% fill. [1] [2] One study coated 175 kg. [3]	Range in kg for your tablets.
Pan diameter (mm)	Drum size and length.	Diameter and length.
Spray nozzle count (pcs)	Three guns in one production study. [3]	Count and spacing.
Air flow rate (m³/h)	Example: 2,200 m³/h inlet. [3]	Range under recipe.
Control system type	iFix recipe and data system; Part 11-compliant system claimed. [2] [1]	Platform and audit trail.
Operating pressure (MPa)	Example atomising air 1.5 bar (0.15 MPa). [3]	Atomising and pattern air.
Temperature range (°C)	Example: inlet 52 °C, exhaust 38–40 °C. [3]	Inlet and exhaust ranges.
Humidity range (%RH)	Inlet water content 7.6 g/kg in one study. [3]	Dehumidification range.
Coating uniformity (%)	Measured as inter-tablet variability. [3]	Method and result on your batch.
Spray rate (L/min)	Example: 300 mL/min. [3]	Range per gun.
Electrical power (kW)	Drum, fans and pumps.	Installed load.
Voltage (V AC)	Plant supply.	Voltage and frequency.
Ingress protection	Washdown rating of enclosures.	IP rating per panel.
Material grade	Product-contact steel.	Grade and certificates.

Send the batch, automation and data requirements together

Paste it into your enquiry below or into an email to a maker, then replace every bracket.

Tablets: [size; shape; core mass]
Batch: [volume range; fill level]
Coating: [system; aqueous or organic; weight gain]
Automation: [closed loading; sampling; discharge; washing]
Controls: [Part 11; GAMP 5; ATEX; data interface]
In-line sensing: [type; port]
Documents: [validation pack; cleaning validation]

See manufacturer records Send an enquiry through CNFX

Buyer questions

What batch range can one automated coater run?

ACG lists 10–100% batch occupancy, 140–1,400 L on its 1400 model; Bohle gives 65–650 L for a BFC 400. [1] [2]

Can coating thickness be measured during the run?

Yes; a Cambridge study fitted a terahertz sensor to a production coater and reached RMSE 5.8 µm against off-line measurement. [3]

What does the control system record?

Bohle lists long-term measured values, alarms, messages, recipes and external data interfaces. [2]

Sources and what still needs a direct check

Sources checked 2026-10-12. ACG and L.B. Bohle are coater makers describing their own machines; the terahertz study is peer-reviewed work by the University of Cambridge, the University of Liverpool and TeraView on a production coater.

ACG — SMARTCOATER 1400 X•ONE datasheet ↗ Maker datasheet Return to text ↑
L.B. Bohle — Tablet coating: optimal uniformity and flexibility, tablet coater saves resources (International Pharmaceutical Industry, Autumn 2023) ↗ Maker application note in trade journal Return to text ↑
Lin H. et al. — Impact of processing conditions on inter-tablet coating thickness variations measured by terahertz in-line sensing, J Pharm Sci 104:2513–2522 (2015), PMC ↗ Peer-reviewed study Return to text ↑

Still to check yourself

List which steps run with the door closed.
Obtain the control system validation and audit-trail documents.
Obtain the washing recipe and cleaning validation data.
Decide whether to fit an in-line sensor and how it sets the end point.
Verify the legal supplier and factory.