5
Precautions
1. Caution on design
Warning
1. Confirm the specifications.
- Give careful consideration to operating conditions such as the application, fluid and environment,
and use the product within the operating ranges specified in this catalog.
- The product is provided for physical, chemical and industrial equipment.
2. Fluids
- When ignitable fluid is used, use a product with metal wetted parts (aluminum, stainless steel).
Always take countermeasures against static electricity.
- For the compatibility between the materials composing the product and the fluids, check the
compatibility check list. Since the compatibility of the fluid used may vary depending on its type,
additives, concentration, temperature, etc., give sufficient consideration when selecting the
material.
- For fluids other than those listed on the check list, please consult us. Also, use them within the
range of the operating fluid temperatures.
- If foreign matters are mixed in the fluid, these may cause abrasion of the inside of the pump
resulting in a problem. Use an appropriate filter (strainer) to remove them. In general, 80 to 100
mesh (150 t
o 180 μm) filters are recommended.
- When transferring a coagulable liquid, take measures to prevent it from coagulating in the pump.
- Please contact SMC sales office for the use of slurry.
- Take countermeasures to prevent the operating fluid from getting onto the body of the process
pump.
3. Water hammer
If a valve is operated abruptly etc., a high pressure may be applied due to water hammer. Take
measures to prevent pressures higher than specified from being applied.
<Examples of measures>
- Use a water hammer resistant valve to reduce the valve closing speed.
- Use an elastic piping material such as rubber hose or an accumulator to absorb the impact
pressure.
4. Liquid seals
To ensure that fluid does not become sealed inside the process pump, when
stopping the pump, relieve the discharge pressure inside it. As shown in the
figure at right, make a circuit which has a relief valve installed on the
system.
5. Fluid pressure supplied to the process pump
Feeding the fluid from the suction side into the pump under pressure, or
Drawing it using a negative pressure, will reduce the life of the pump.
6. Ensure space for maintenance.
Secure the space required for maintenance and inspection. Take into consideration also leakage
from the product. When transferring a flammable liquid or a liquid that may affect the human body
or environment, take measures including fire ban and keeping the area off limits.
7. When the diaphragm is broken, supply air will be mixed with the fluid or the fluid will enter
the air switching valve. This may affect the product performance, or the chemical
resistance of the components may not be suitable. Countermeasures need to be taken by
the customer.
8. Use a design which prevents reverse pressure and reverse flow.
If reverse pressure or reverse flow occurs on the discharge side of the process pump, the
equipment is liable to become damaged or malfunction. Take safety measures in designing the
circuit.
9. Measures against static electricity
Take measures against static electricity as static electricity may occur depending on the fluid.
Particularly, when circulating flammable fluid through the pump, be sure to take measures to
prevent the occurrence of static electricity.
10. The pump cannot transfer gas. Do not allow it to idle for a long time.
If the pump is operated for a long time without any fluid inside or in a gas-fluid mixed state, the
diaphragm may be damaged or the life may be shortened. Do not continue idling except for
priming the pump.
