Pharmaceutical

Introduction
On a pharmaceutical line, water is never just water. It carries particles into clean areas, it lifts labels a few hours after they have been applied, it softens cartons in storage and it disturbs the inspection processes that the whole batch depends on. The drying station sits quietly between washing and filling, or between washing and labelling, and it decides whether the rest of the line behaves predictably.
This is why more pharmaceutical manufacturers are replacing open compressed-air nozzles with a blower-driven air knife system. The change is rarely about the price of a nozzle. It is about repeatability, particle control and the running cost of an operation that runs every shift of the year.
The video above shows one of these systems in operation on an infusion container line, filmed at a customer's plant. This article explains what the equipment is doing, how it is configured for pharmaceutical production, and what information is needed to specify it.
Why the Drying Step Matters More Than It Appears
After washing or rinsing, containers leave the washer with a film of water on the body, the shoulder and the base. Where that water remains, several problems follow at once.
Particle control. Water droplets transport particles. In a clean area, removing the liquid at the point where it is introduced is far easier than removing it after it has spread.
Labelling and printing. Adhesive will not bond properly to a wet surface. Labels lift at the edge within hours, and inkjet codes applied to a damp surface smear or fail inspection. Both create rework or rejected product.
Inspection and packaging. Water spots are read as defects by vision systems and human inspectors, and moisture trapped under a shrink sleeve or inside a carton creates quality complaints after the batch has left the plant.
Contamination risk. Standing water is where microbial growth begins, which is why drying is treated as a controlled step rather than a finishing detail.
How Blower and Air Knife Work Together
A blower-driven air knife system has two halves. The blower — a ring blower, side channel blower or centrifugal blower depending on the required flow and pressure — produces a high volume of air at low pressure. That air travels through a short hose to the air knife, a hollow body with a precisely machined slot running along its length.
Inside the knife, the air is forced through the slot and then flows over a curved lip. The Coanda effect keeps the stream attached to that surface, and as it travels it draws in surrounding air and pulls it into the stream. One unit of supplied air therefore moves many times its own volume, and the result is a thin, flat, high-velocity curtain across the full working width.
For a pharmaceutical line, the practical consequences of this design matter as much as the drying performance. The curtain is uniform from one end of the knife to the other, so every container on the conveyor receives identical treatment. There is no mechanical contact, no heat and nothing to transfer onto the product surface. And because the airflow is driven by a dedicated blower rather than drawn from the compressed-air network, there is no risk of oil carryover from the compressor reaching a container or component.
Inside an Infusion Container Line
The footage in the video above was recorded on a customer's production line handling infusion containers. The unit sits directly after the washing stage, with knives positioned to cover the container body and the areas where water collects after rinsing.
Three details are worth pointing out, because they apply to almost every pharmaceutical installation.
The knives are positioned by where the water sits, not by where it is convenient to mount them. A single top-mounted knife is rarely enough when the base and the lower body are wet. Side knives angled in the direction of travel push the film off the container instead of atomising it into a mist that settles further down the line.
The system is sized to the line, not to a catalogue page. Slot width, knife length, air velocity and blower model are selected against the container geometry, the conveyor width and the actual line speed. Under-sizing produces a curtain that fades at one end; over-sizing produces noise, mist and wasted energy.
The blower runs on demand. On lines that stop and start, a variable-frequency drive or a simple interlock lets the airflow follow production instead of running at full output during every stoppage.
Configuring for Pharmaceutical Production
Pharmaceutical installations share a set of requirements that shape the equipment specification.
Material and cleaning. Stainless steel construction, typically SS304 for general use and SS316 where cleaning agents are aggressive, is standard for knives and mounting hardware. Brackets should be easy to remove so the equipment itself can be cleaned as part of the routine.
Air quality. The air delivered to the product can be filtered to the cleanliness level the process requires. Because the blower draws ambient air, the position of the intake and the filtration stage are part of the design conversation rather than an afterthought.
No lubrication, no particles. The air knife has no moving parts inside it. There is nothing to wear, nothing to lubricate in the air path, and no mechanism generating particles above the product.
Noise. Filling and packaging halls are already close to noise limits. A silenced blower and a well-designed enclosure are usually specified from the start, and lower velocity operation through a multi-stage layout is often quieter than one aggressive stage.
Documentation. Buyers increasingly ask for material certificates, motor efficiency data and test records. These should be requested at the quotation stage so they arrive with the equipment rather than after it.
Where These Systems Are Used
The same principle covers a wide range of pharmaceutical applications:
- Vials and ampoules dried after washing, before filling or inspection
- Infusion containers and bottles dried before labelling and coding
- Tablet and capsule dedusting after coating, before blister packaging
- Blister and carton surfaces cleared before sealing
- Equipment, trays and tooling dried after cleaning in washdown areas
In each case, the objective is the same: remove the liquid at the point where it appears, without contact and without adding heat.
What It Costs to Run
Compressed air is the most expensive utility in most plants, because a large share of the electricity used to produce it is lost as heat before the air reaches the point of use. A dedicated blower produces air at exactly the volume and pressure the knife needs, so the energy is spent on the drying process rather than on pressure that will be discarded.
Two further factors lower the running cost. The air knife has no moving parts, so performance stays stable over long production runs and maintenance is limited to routine filter and bearing checks on the blower. And where high-efficiency motors and variable-frequency control are specified, output can follow the real demand of the line.
For a station running two or three shifts, the energy difference between an open compressed-air nozzle and a matched blower-driven air knife is usually the largest single line item in the business case, and it is the reason many projects are approved on running cost alone.
What to Send Us
To recommend a configuration, we need the container or component type and dimensions, the conveyor width, the maximum and minimum line speed, the position on the line where drying is required, the cleanliness requirement and the number of shifts per day. Photographs or a short video of the installation area are more useful than a written description, because they show how much space is available and where the water actually collects.
SCB Vacuum Tech Limited designs and manufactures air knives, air amplifiers and the ring, centrifugal and turbo blowers that drive them as a matched system, and supports customers from the initial application review through to installation and adjustment. Send us your line details and our engineers will propose a layout, including the number of knives, mounting angles, slot width and blower model, together with the expected power consumption so the proposal can be evaluated on running cost as well as purchase price.
SCB Vacuum Tech Limited
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