Diaphragm Valves Industry Information
A diaphragm valve is a shutoff or control valve with
a flexible membrane, or diaphragm, which seals the valve completely or
partially once the valve is engaged. Once the actuator is engaged, a
stem within the valve pushes a plug or compressor against the diaphragm.
The diaphragm is pushed against a raised section of the valve, creating
a seal. This seal stops the flow of liquid, gas or other material through
the valve. Diaphragm valves are able to seal more tightly than other
types of valves due to their flexible membrane.
Diaphragm valve manufacturers offer many valve configurations and make
their products out of a variety of metals and plastics. The material
from which a diaphragm valve is constructed is dependant upon its intended
use and compatibility with certain fluids. Diaphragm valve manufacturers
have adapted their products for the biotech and medical industries, using
materials that can withstand being sanitized and sterilized. Diaphragm
valves may be operated manually, pneumatically (using air pressure to
move the diaphragm) or hydraulically (using fluid pressure to move the
diaphragm).
Diaphragm valve manufacturers offer two main product categories. One
type is a saddle, or weir, valve and the other is a seat, or straight-way,
valve. The most important difference between these two types of diaphragm
valves is that the saddle valve has its two ports in line with each other
on opposite sides of the valve. The seat-type valve has in and out ports
located at a 90 degree angle from each other. Although diaphragm valves
usually come in two-port forms, they can also have three ports or more.
Diaphragm valves perform extremely important functions in a wide range
of industries. They are used to monitor and control the flow of many
materials and are often considered process valves because they can be
used in drinking water treatment, sea water desalination and processes
involving energy production, agriculture, food science, pharmaceuticals,
medical manufacturing, mining, pulp and paper products, chemical and
waste treatment, food and beverage production, and the powder and bulk
industries.