Are you a ceramics industry professional who needs advice on how to select the right pumping unit? Continue reading then, because you are in for some good advices.

The processes in a ceramic production plant, pose singularities that can make choosing the correct pump a challenging job. Pumping fluids such as slip, ceramic glazes and wastewater is a common task in this industry. These processes require robust, versatile pumps, capable of pumping fluids that often contain suspended solids.

Whatever your application within the ceramic industry, from SAMOA we recommend the use of Air operated double diaphragm pumps (AODDP).

This article will teach you:

1. How double diaphragm pumps (AODD) work and why choose them, over other pumping alternatives.
2. In which specific applications within the ceramic industry are these pumps used and the most appropriate models for each of these applications.
3. Installation example to reflect their functionality.

Double diaphragm pumps (AODD): how they work and why are they recommended for the ceramics industry?

• These pumps offer high flow rates (up to 1,000 l/min (264 US gal/min) with the possibility of regulating the flow rate, according to your needs.
• Allow the passage of solids in suspension without modifying the temperature of the fluid they are pumping.
• Resistant to abrasive fluids, frequently present in ceramic processes.
• Reduced energy consumption compared to other pumps (such as electric pumps).
• Longer life if compared to other pumps, so maintenance costs are lower.
• Easier maintenance by reducing the number of pump parts which implies a shorter downtime.
• Bolted design to prevent possible leaks, same size bolts in covers and manifolds for easier servicing.
• Possibility of ATEX certification, pumps are designed to be able to work in potentially explosive environments.

In which applications are AODD pumps used and which models do we recommend?

1.  Ceramic glazes or colors: Preparation and formulation

These glazes are made from a mixture of inorganic chemicals called frits. These chemicals come as granules or flakes and are mixed with water. This procedure to make ceramic colors, which are later applied on porcelain, pavement, stoneware, tiles, etc.

• For this application we recommend 2″ metallic pumps, with Hytrel or Santoprene membranes. Such diaphragms are resistant to suspended solids and also highly flexible. In terms of abrasion Hytrel has a much higher resistance than Santoprene.

2.  Dispensing and color kitchen:

AODD pumps are used in dispensing or special color kitchen processes for specific industries such as ceramics.

• Smaller pumps such as 1″ are the best choice for this application, due to the reduced flow rates required. Pump materials will depend on the fluid’s technical data sheet.

3.  Spray:

Double Diaphragm pumps are also included in the application of ceramic glazes or spraying processes.

• We recommend ½” or 1″ AODD pumps for finishing applications where high flow rates aren’t required. If pumping solvent-based paint, always choose aluminium pumps with Teflon diaphragms. However, for water-based paint, the best option is aluminium pumps with Santoprene diaphragms.

4.  Tile printing:

Tile printing processes also incorporate AODD pumps. Once molds are made, they are sent to the printing line.

• Printing lines are like rotary printers for paper, only here, materials such as tiles or stoneware is what gets printed, using ceramic colors. Pumps are used to transfer ceramic colors from 20-40 litre tanks to the printing rollers.

5.  Ceramic Barbotine:

Ceramic barbotine and paste transfer processes also allow for the use of AODD pumps.

• These applications require high flow rates. Hence, we opt for 3″ pumps. Regarding pump materials, we also recommend metallic pumps with Hytrel or Santoprene diaphragms, given their flexibility to suspended solids passage and resistance to abrasion.
   

6.  Water treatment:

AODD pumps are used in wastewater treatment processes. Water needs to be treated at all ceramic plants, before it’s discharged into the system.

• We recommend 2″ pumps with aluminium body and Hytrel or Santoprene diaphragms. Our choice is based on the fact that these materials are highly resistant to the passage of suspended solids and offer great flexibility. Teflon is not the best match because even though provides greater chemical compatibility than Hytrel or Santoprene, its lack of flexibility can lead to irreversible deformations that may cause fluid leakage due to diaphragm failure. It is therefore unsuitable for these specific applications.

Installation example

Now, let’s put into practice the importance of AODD pumps in the ceramic industry. We have gathered this installation example we would like you to analyse: