Air Valve Technology

Air valve technology is the heart of the air-powered double diaphragm pump and determines reliability. Yamada holds three patents on it's field proven valve and enjoys a superior reputation throughout the industry.

Unified Air Valve Concept
To simplify, Yamada offers two common size air valve assemblies within five sizes of pumps (3/4" & 1" pumps and 1-1/2", 2" & 3" pumps) further reducing reassembly confusion and parts inventory. Other air-powered double diaphragm pump manufacturers offer multiple air valve designs and revisions in an effort to address pump reliability problems. Yamada offers one field proven design.

Truly Non-Lubricated Air Valve
The patented air valve on all NDP series pumps never requires lubrication or prepacking. The advanced design eliminates the need for the external lubrication which can lead to pumpage contamination and maintenance headaches. Yamada is proud to be the originator of non-lubricated air valve technology for air-powered double diaphragm pumps.

Component Replaceable
All Yamada air valves can be restored with individual components, without requiring complete valve and housing replacement.

Non- Stalling
A patented non-centering, spring-assisted shifter is incorporated into every NDP series pump, ensuring a positive shift every time. The 304 stainless steel C-springs provide exceptional durability and longevity and are tested to last over 300 million cycles. The spring assist also aides in long dead head applications for reliable startup.