Revised Standard from Last Update.

1. SCOPE

1.1 This standard deals with manual and automatic backflow media filters and applies to:

a) manually cleaning filters.

b) complete automatic filters at a single unit level.

c) a filtration battery which is a complete filter system that includes:

1) Inlet - Unfiltered supply water;

2) Outlet - Filtered water carried to the irrigation network; and

3) Back flush outlet - This is for the water and filtrate, flushed out during the backflow procedure.

d) Command power source - Usually hydraulic-filtered water for automatic operation (can also be pneumatic or electric).

1.2 This standard specifies the construction requirements and test methods for “granulated media filters”, hereinafter called media filters, intended for operation in agricultural irrigation systems. It includes manual cleaning media filters and automatic self-cleaning media filter “batteries” (2 units or more working in parallel).

1.3 This standard deals with the operation and performance of a media filter including related valves, backwash mechanism, under-drains, manifolds and all related accessories necessary for the operation of the filter.

1.4 This standard deals only with pressurized filters operating in a range of filtration velocities declared by the manufacturer. The standard does not deal with filtration ability, efficiency and capacity (quality of filtered water, time of operation before media filter becomes entirely clogged, etc).

2. REFERENCES

2.1 The standards listed below contain provisions which, through reference in this text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards listed below. In case the standards are to be referred in this clause they are to be listed as follows:

2 : 1960 Rules for rounding off numerical values (revised)

554 : 1999/ISO 7-1 Pipe threads where pressure - Tight joints are made on the threads - Dimensions, tolerances and designation (fourth revision)

6418 : 1971 Cast iron and malleable cast iron flanges for general engineering purposes

2405 (Part 1) : 1980 Industrial sieves: Part 1 Wire cloth sieves

2405 (Part 2) : 1980 Industrial sieves: Part 2 Perforated plates

10483 : 1983/ISO/DIS 7806 Code for designating perforations of industrial plate sieves

12785 : 1994 Irrigation equipment - Strainertype - Filters