Reverse-air manifold and flow passage module

A reverse-air manifold and flow passage module for use in connecting a main gas manifold to bag houses, said module comprising:

• a. spaced-apart horizontal plates forming the top and bottom of said module,
• b. spaced-apart vertical side plates,
• c. spaced-apart vertical end plates,
• d. a pair of spaced-apart vertical partitions
• extending the length of said module, said partitions and horizontal plates bounding and forming a portion of a reverseair manifold centrally of said module, said portion being open at its ends,
• e. said module having two valve chambers therein, one on each side of said reverse-air manifold portion, each valve chamber being bounded by one of said partitions, one of said side plates, said end plates and said horizontal plates,
• f. means forming a first gas flow passage through one of said horizontal plates into each of said valve chambers, each such first gas flow passage terminating in an annular valve seat opening into said valve chamber and facing the other of said horizontal plates,
• g. means forming a second gas flow passage within said module from said reverse-air manifold portion into each valve chamber on either side thereof, each such second gas flow passage terminating in an annular valve seat opening into said valve chamber and facing the said other of said horizontal plates, whereby the valve seats of said first and second gas flow passages face in the same direction,
• h. means forming a third gas flow passage opening into each of said valve chambers through the side plate of said module bounding the valve chamber.