Use of SCHMITT Pumps in PCB Manufacturing
Application Background
The production of printed circuit boards and chip carriers combines mechanical processing with numerous wet chemical and electrochemical process steps. Pumps supply spray nozzles, circulate process, overflow, and rinsing baths, convey regeneration solutions, and handle transfer and wastewater tasks.
Here, high demands on system availability and reproducible process conditions meet acidic, alkaline, oxidizing, or metal-containing media. For a reliable design, the fluid, concentration, temperature, density, solids content, and the required operating point must be considered together.
Challenge
During cleaning, developing, stripping, etching, and chemical and electrolytic metallization, very different bath chemicals are used. Depending on the process, corrosion, temperature, crystallizing salts, particles, or metallic residues can affect pump materials, bearings, and seals.
At the same time, flow rate and discharge pressure influence the supply to spray nozzles, filters, and bath circulation systems. Therefore, a pump must operate reliably at the designated operating point. The selection of materials and seals is always media-specific; PP, PVDF, elastomers, and sliding bearing materials are not universally suitable for every PCB bath.
Solution
For many aggressive etching, cleaning, rinsing and metallization fluids, NHM and MPN magnetically coupled plastic pumps are the preferred solution. Because they have no dynamic shaft seal, they provide hermetically sealed pumping. PP or PVDF is selected according to the specific chemical medium and temperature.
The NHM combines a broad performance range with efficiency of up to 76%. Our patent-pending NHM plain-bearing solution uses an externally mounted, oversized SiC design without a plug-in shaft and provides a robust design advantage for defined levels of particles, crystals or precipitates. The MPN is a compact mag-drive pump proven over decades in many circulation, spray and transfer duties.
For vertical installation in open tanks, the dry-run-safe, sealless T series is available. The U series is a robust PVDF alternative with a mechanical seal, for example when ferromagnetic particles rule out a magnetic coupling. Particle-sensitive process baths still require suitable filtration and a project-specific assessment of the bath chemistry.
Advantages of SCHMITT Pumps in PCB Manufacturing
NHM and MPN operate without dynamic shaft seals. This reduces the leakage risk with aggressive or environmentally hazardous fluids.
PP, PVDF and appropriate elastomers and plain-bearing materials are selected to suit the fluid chemistry, concentration and temperature.
Pump sizing is matched to the required flow rate and discharge pressure of spray nozzles, filters and bath circuits.
The externally mounted, oversized NHM design without a plug-in shaft tolerates defined levels of particles, crystals and precipitates better than conventional plug-in-shaft solutions.
The optimised hydraulics of the NHM achieve an efficiency of up to 76% depending on the operating point.
Horizontal NHM, MPN and U pumps, together with the vertical T series suitable for dry running, cover a wide range of system layouts and tank configurations.
Pumps for PCB Manufacturing
- Hermetically sealed, magnetic coupling, PP or PVDF
- Up to 95 °C, flow rate up to 42 m³/h, head up to 27 m
- Up to 76% efficiency: best-in-class energy efficiency
- Sliding shaft technology: wear-free, maintenance-free and durable
- Hermetically sealed by contactless magnetic drive
- Special containment shell geometry for high pressures and temperatures
- Hermetically sealed, magnetic drive, PP or PVDF
- Up to 95 °C, flow rate up to 35 m³/h, head up to 32 m
- Extremely proven pump, used in more than 10,000 applications
- Insensitive to insufficient lubrication and partial dry running due to generously dimensioned plain bearings – no plug-in shaft
- Virtually maintenance-free in normal operation due to generously dimensioned plain bearings
SCHMITT Pumps
Horizontal plastic pumps
Vertical plastic pumps
