Abstract:
A method and apparatus for testing the functionality of automatic air valves positioned at high points of a pipeline system are provided. The invention generally provides a testing flange and a process for performing various fluid pressure tests to determine whether automatic air valves are properly releasing and/or stabilizing air within a pipeline system.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Embodiments of the present invention generally relate to an apparatus and process for field testing automatic air valves in water and wastewater pipeline systems. 
     2. Description of the Related Art 
     The operation of water and wastewater pipeline systems may be severely impacted by the presence of air trapped in the pipeline. In fact, failure to properly de-aerate the line may lead to pump, valve, and pipe failures as well as faulty instrument readings. 
     Air in a pressurized, operating pipeline comes from three primary sources: air initially present in the line prior to startup, air or gas contained or generated within the water or wastewater itself, and air that enters the line through mechanical equipment. 
     Regardless of the source, the air present in the line tends to accumulate at high points in the line. This condition may lead to a host of problems in the pipeline, including line restriction, flow stoppage, or high pressure surge (water hammer). 
     In addition to the problem of trapped air in water and wastewater pipelines, vacuum or siphoning of the line may occur during a system shut down or failure. Such a condition may lead to line collapse or intensified surges in the pipeline. 
     To help alleviate the existence of trapped air or vacuum in water and wastewater pipeline systems, most municipalities employ automatic air valves at the high points in the line. Types of automatic air valves include air/vacuum valves, air release valves and combination air valves. 
     An air/vacuum valve exhausts large quantities of air upon system start-up, as well as allowing air to re-enter the line upon system shut down or system failure. As water enters an air/vacuum valve, a float rises, closing a discharge port. The port, and hence the valve, will remain closed until the air pressure in the valve drops to atmospheric pressure. Furthermore, if a negative pressure develops in the line, the valve opens, admitting air into the line and preventing the deleterious effect of vacuum or siphoning in the system. 
     An air release valve continuously releases accumulated air during system operation. Similar to the air/vacuum valve, a float closes a discharge port as the water rises in the valve. During operation, as air from the line enters the valve, it displaces the water. As a result, a float drops from its sealed position against the discharge port, allowing the air to release to the atmosphere. As the air is vented, it is replaced by water, raising the float and closing the valve. As air accumulates, the valve continues to cycle in this manner to remove the collected air. 
     A combination air valve performs the functions of both an air/vacuum valve and an air release valve. Therefore, the combination air valve exhausts large quantities of air on start-up, admits air on shutdown or failure, and releases air continuously during operation. 
     However, as important as these valves are to the proper functioning and life of water and wastewater pipeline systems, a shortage of apparatus and procedures exist for ensuring proper functioning of these valves in the field. Accordingly, a need exists for improved apparatus and processes for testing automatic air valves in water and wastewater pipeline systems. 
     SUMMARY OF THE INVENTION 
     The present invention generally relates to an apparatus and process for field testing the functioning of automatic air valves in water and wastewater pipeline systems. 
     In one embodiment, a process for field testing an automatic air valve connected to a testing apparatus in fluid communication with an auxiliary valve situated at a pipeline system high point comprises closing the auxiliary valve, draining the testing apparatus, applying pressurized air to the testing apparatus, monitoring the testing apparatus, and determining whether the automatic air valve is releasing air. 
     In another embodiment, a process for field testing an automatic air valve connected to a testing apparatus in fluid communication with an auxiliary valve situated at a pipeline system high point comprises closing the auxiliary valve, draining the testing apparatus, applying pressurized air to the testing apparatus, monitoring the testing apparatus, determining whether the automatic air valve is releasing air, applying a test fluid to the testing apparatus, monitoring the testing apparatus and the air valve, and determining whether the automatic air valve is closing. 
     In another embodiment, a process for field testing an automatic air valve connected to a testing apparatus in fluid communication with an auxiliary valve situated at a pipeline system high point comprises closing the auxiliary valve, applying a vacuum to the testing apparatus, monitoring the testing apparatus and the air valve, and determining whether the air valve is allowing air to enter the testing apparatus. 
     In yet another embodiment, an apparatus for connection with a pipeline system comprises a flange member having an inner body portion in fluid communication with first and second flange openings, the first flange opening being for connection with the pipeline system, the second flange opening being in connection with an automatic air valve, a first fluid port in fluid communication with the inner body portion of the flange member, a first stop valve in fluid communication with the first fluid port, a second fluid port in fluid communication with the inner body portion of the flange member, and a gauge in fluid communication with the second fluid port. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIG. 1A  is a schematic top view of an embodiment of the present invention. 
         FIG. 1B  is a schematic front view of the embodiment depicted in  FIG. 1A . 
         FIG. 2  is a schematic, cross-sectional front view of an exemplary air valve that may be used with the present invention. 
         FIG. 3  is a schematic, cross-sectional front view of an embodiment of the test flange in  FIGS. 1A and 1B . 
         FIG. 4  is a flow diagram of an embodiment of a process of the present invention. 
         FIG. 5  is a flow diagram of another embodiment of a process of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention generally relates to an apparatus and process for field testing the functioning of automatic air valves in water and wastewater pipeline systems. 
       FIG. 1A  is a schematic top view and  FIG. 1B  is a schematic front view of an embodiment of an apparatus  100  for field testing automatic air valves in water and wastewater pipeline systems. An auxiliary shut-off valve  110  may be positioned to extend from a pipeline system high point, where trapped air tends to accumulate. A test flange  120  may be positioned between auxiliary shut-off valve  110  and an automatic air valve  125  (omitted from  FIG. 1A  for clarity of other features of the invention). A cross-sectional, front view of an exemplary air valve  125  is shown in  FIG. 1C . The automatic air valve  125  may have a float component  127  for closing and opening the air and/or vacuum release portion of air valve  125 . The automatic air valve  125  may be an air/vacuum valve, an air relief valve, a combination air valve, or other air valve for relieving trapped air and/or vacuum situations within the pipeline system. 
     A schematic, cross-sectional front view of an embodiment of the test flange  120  is shown in  FIG. 3 . The test flange  120  may have a first opening  122  in fluid communication with a second opening  124  via an inner body portion  126 . The test flange  120 , for example, may be a two inch diameter flange having an outer diameter of six inches and a bolt-hole circle pattern diameter of 4-¾ inches. The test flange  120  may further include a port  130  for introducing fluid into or removing fluid from the test flange  120 . The port  130  may be any size and configuration conventional in the art for connecting a fluid conduit member. As an example, port  130  may be drilled and tapped for a one inch NPT pipe fitting. 
     A stop valve  140  may be connected in line with the port  130  for allowing or preventing external fluid communication with the port  130 . The stop valve  140  may be any of a variety of valves known in the art for shutting off fluid flow, such as a ball valve, a gate valve, or a butterfly valve. 
     Test flange  120  may have a test port  160  in fluid communication with the inner body portion  126  and configured for connection with a gauge  170 . Test port  160  may be any size or configuration conventional in the art for connecting to a fluid conduit member. For example, test port  160  may be drilled and tapped for a one inch NPT pipe fitting. The gauge  170  may be any of a variety of gauges used in fluid systems for determining operating parameters such as the existing pressure in the system. 
     A stop valve  190  may be positioned between the port  160  and the gauge  170 . The stop valve  190  may be any of a variety of valves known in the art for shutting off fluid flow, such as a ball valve, a gate valve, or a butterfly valve. 
     The test flange  120  may include an additional port  150  in fluid communication with the inner body portion  126 . Port  150  may also be any size or configuration conventional in the art for connecting a fluid conduit member. For instance, port  150  may be drilled and tapped for a one inch NPT pipe fitting. 
     Additionally, a stop valve  180  may be connected in line with the port  150  for allowing or preventing external fluid communication with the port  150 . The stop valve  180  may be any of a variety of valves known in the art for shutting off fluid flow, such as a ball valve, a gate valve, or a butterfly valve. 
       FIG. 4  is a flow diagram of an embodiment of a process  400  for field testing an automatic air valve  125  in a water or wastewater pipeline system. One embodiment of process  400  pertains to an embodiment of the apparatus  100  wherein the port  150  and stop valve  180  are not provided. 
     In step  410 , the auxiliary valve  110  may be closed to shut off flow from the pipeline. 
     In step  420 , the stop valve  140  may be opened and water drained from the system. The stop valve  140  may then be closed. 
     In step  430  a pressurized air source may be connected to the stop valve  140 . Pressurized air may be supplied to the stop valve  140  via the pressurized air source, and the stop valve  140  may be shifted to the open position to allow the pressurized air to flow into the air valve  125  through the test flange  120 . Pressurized air may be supplied at a pressure of about 25 psi to about 250 psi. 
     In step  440 , the air valve  125  and the gauge  170  may be monitored to determine whether the air valve  125  is properly relieving air pressure. That is, if the air pressure in the system rises and is not released through the air valve  125 , the air valve  125  is not functioning properly. Conversely, if the air pressure in the system is released through the air valve  125 , the air valve  125  is releasing air properly. 
     If the air valve  125  is releasing air properly, optional steps may be added to determine whether air valve  125  is closing properly. 
     In optional step  450 , the stop valve  140  may be closed and the air source removed. In its place, a test fluid source, such as water, may be connected in line with the stop valve  140 , and the stop valve  140  may be opened. 
     In optional step  460 , the air valve  125  and the gauge  170  may be monitored to determine whether air valve  125  is closing properly. For example, if test fluid leaks out of the air valve  125  as the system fills with test fluid, the air valve  125  is not closing properly. However, if the air valve releases air as the system fills with test fluid, but the test fluid does not leak out of the valve once the system is full of test fluid, the air valve  125  is closing properly. Further, in step  460 , the air valve  125  may be visually monitored to determine whether any leaks exist in the system. 
     In optional step  470 , the stop valve  140  may be closed and the test fluid source removed. The stop valve  140  may then be opened, and test fluid from the system may be drained and measured to determine whether the float component  127  of air valve  125  is properly inflated. For example, if the volume of test fluid removed from the system approximately equals the known volume of the flange  120 /air valve  125  combination, then the float component is properly inflated. However, if the volume of test fluid removed is greater than the flange  120 /air valve  125  combination, then the float component is not properly inflated. 
     In optional step  480 , the stop valve  140  may be closed and steps  430 - 470  may be repeated as necessary to ensure air valve  125  is functioning properly. 
     Another embodiment of process  400  pertains to an embodiment of apparatus  100  wherein port  150  and stop valve  180  are provided. 
     In step  410 , the auxiliary valve  110  may be closed to shut off flow from the pipeline. 
     In step  420 , the stop valve  140  may be opened and water drained from the system. The stop valve  140  may then be closed. 
     In step  430  a pressurized air source may be connected to the stop valve  140 . Pressurized air may be supplied to the stop valve  140  via the pressurized air source, and the stop valve  140  may be shifted to the open position to allow the pressurized air to flow into the air valve  125  through the test flange  120 . Pressurized air may be supplied at a pressure of about 25 psi to about 250 psi. 
     In step  440 , the air valve  125  and the gauge  170  may be monitored to determine whether the air valve  125  is properly relieving air pressure. That is, if the air pressure in the system rises and is not released through the air valve  125 , the air valve  125  is not functioning properly. Conversely, if the air pressure in the system is released through the air valve  125 , the air valve  125  is releasing air properly. 
     If the air valve  125  is releasing air properly, optional steps may be added to determine whether air valve  125  is closing properly. 
     In optional step  450 , the stop valve  140  may be closed, and a test fluid source, such as water, may be connected in line with the stop valve  180 . The stop valve  180  may then be opened. 
     In optional step  460 , the air valve  125  and the gauge  170  may be monitored to determine whether air valve  125  is closing properly. For example, if test fluid leaks out of the air valve  125  as the system fills with water, the air valve  125  is not closing properly. However, if the air valve releases air as the system fills with water, but the test fluid does not leak out of the valve once the system is full of test fluid, the air valve  125  is closing properly. Further, in step  460 , the air valve  125  may be visually monitored to determine whether any leaks exist in the system. 
     In optional step  470 , the stop valve  180  may be closed and the test fluid source removed. The stop valve  180  may then be opened, and the test fluid from the system may be drained and measured to determine whether the float component  127  of air valve  125  is properly inflated. For example, if the volume of test fluid removed from the system approximately equals the known volume of the flange  120 /air valve  125  combination, then the float component is properly inflated. However, if the volume of test fluid removed is greater than the known value of the flange  120 /air valve  125  combination, then the float component is not properly inflated. 
     In optional step  480 , the stop valve  180  may be closed and steps  430 - 470  may be repeated as necessary to ensure air valve  125  is functioning properly. 
       FIG. 5  is a flow diagram of another embodiment of a process  500  for field testing an automatic air valve  125  in a water or wastewater pipeline system. 
     In step  510 , the auxiliary valve  110  may be closed to shut off flow from the pipeline. 
     In step  520  a negative pressure or vacuum source may be connected to the stop valve  140  in line with the inlet port  130 , and negative pressure may be supplied to the stop valve  140  via the pressurized air source. Negative pressure may be supplied at a pressure of from about 0 psi to about −15 psi. The stop valve  140  may be shifted to the open position to allow the negative pressure to flow from the air valve  125  through the test flange  120 . 
     In step  530 , the air valve  125  and the gauge  170  may be monitored to determine whether air valve  125  is properly relieving negative pressure. That is, if the air pressure in the system falls and is not stabilized through the air valve  125 , the air valve  125  is not functioning properly. Conversely, if the negative pressure in the system is stabilized through the air valve  125 , the air valve  125  is allowing air into the system properly. 
     While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.