OPERATION AND MAINTENANCE MANUAL
12-2015
5
surfaces of the valve are covered with powder epoxy paint.
In the cover flange opening there is an access plug with a ¾” thread, which makes it possible to
twist the TYPE 7040 deaerating valve, which is intended to release small quantities of air.
TYPE 7040 valve is a single step valve for water systems, which is made of a brass body 1
and cover 2 connected with a thread by means of an o-ring gasket 10. A metal ball – a float 3 with
density lower than water is suspended from a stainless steel lever 6. The lever has a movable joint
7 with a bolt 8, which is a lever spin axis mounted to the lower cover surface. Ball density is
especially chosen so that during air release via the valve, the ball is positioned in the lower
position (descended lever) and during water filling raised together with the water level. Filling the
chamber with water causes a simultaneous movement of the lever according to spin axis until it
reaches the upper position, where gasket 4 closes the output hole of a nozzle 5.
However, during the aerating the ball, as the water level in the valve chamber decreases, the
nozzle output hole opens and assumes the lower position in the position of descended lever.
During work with a TYPE 7010 valve, the TYPE 7040 valve is a second stage of deaerating
when the ball performs repetitive up and down movements, releasing small amounts of air, which
builds up in the chamber through the half-open nozzle, with 7010 valve still closed and filled with
water (under pressure).
It is recommended to install the air valve in vertical position in the highest point of the
pipeline or in its inflection points.
2.2 MATERIALS
Tables below show a list of materials used in the production of air valves.
TYPE 7010
No.
Part name
Material
Standard
1
Body
Ductile cast iron EN-GJS-400-15
PN-EN 1563: 2012
2
Cover
Ductile cast iron EN-GJS-400-15
PN-EN 1563: 2012
3
Vulcanised ball
Aluminium alloy
covered with rubber: EPDM (or NBR)
PN-EN 1706: 2011
PN-ISO 1629: 2005
4
Caulk ring
Rubber: EPDM (or NBR)
PN-ISO 1629: 2005
5
Caulk ring
Rubber: EPDM (or NBR)
PN-ISO 1629: 2005
6
Hex head screw M16x40
Acc. to subject matter standards
PN-EN ISO 4017: 2011
7
Rootstock 17
Acc. to subject matter standards
PN-EN ISO 7091: 2003
8
Plug ¾”
Brass/chrome plated
acc. to the producer's
Technological Guidelines
