Bypass Port Adaptor Maintenance
DO NOT use a bristle brush, pipe cleaner, or other abrasives to clean the bladder or orifice plate.
DO NOT force bladder removal tool into or out of the bladder. If tool resists movement, loosen screws more before proceeding.
DO NOT assemble or disassemble the valve with anything other than the provided tools – take care with sharp objects around the valve bladder and orifice plate. Do not insert the provided 0.050” hex driver into the inner diameter of the bladder. This may result in immediate or latent bladder damage. Only insert the insertion removal tool into the inner diameter of the bladder.
DO NOT use a bladder for more than 30 days, 25 ten minute cleaning cycles or 25 swab cycles, or 1000 actuation cycles (whichever comes first.)
DO NOT autoclave the push connect elbow or other items that are screwed into the external flat atop the bypass port adapter.
ALWAYS test the bypass adapter in the test fixture 014560-001 after changing the bladder. Bladders should also be tested if the system is unable to maintain user selected tower pressure or if a bypass port adapter failure is suspected for any other reason. The bypass port adapter may also be tested before or after a study at the user’s discretion.
NOTE: Care must be taken to ensure operation of the bypass valve. Valve bladders should be cleaned after each exposure and bladders should be replaced monthly with replacement bladders from 601-3013-001.
Valve bladders can be cleaned or sterilized with a household bleach solution (6% Sodium Hypochlorite), 80% ethanol, or in a 120°C autoclave.
LIGHT SWAB CLEANING: Bladders can be gently swabbed with a cotton swab dipped bleach or ethanol without disassembling. The swab should be used to wipe the inside of the jet (shown in yellow below). This hole delivers aerosol to the animal and stops aerosol flow when the bypass function is activated.
The 6 small holes (shown in red below) at the tip of the aerosol jet should be inspected for aerosol deposition and swabbed. These holes provide fresh air flow to an animal when the bypass is activated. If they become occluded with aerosol from previous studies and are not cleaned, an animal may suffocate. If these holes cannot be cleared with a swab, then the port should be washed following wash instructions below.
The 8 medium holes (shown in blue) on the floor of the adapter vent aerosol to the outflow lines. These holes may should also be inspected & swabbed to ensure proper aerosol flow.
WASH / AUTOCLAVE / STERILIZATION INSTRUCTIONS: To wash, sterilize, or autoclave a port adapter, the bladder and valve stem must be disassembled from the port adapter following disassembly instructions below.
DO NOT autoclave the valve stem and elbow. These parts are shown in black in the images below.
Disassembled Components may then be: 1) submerged in bleach or ethanol, agitating the cleaning solution until clean, AND/OR 2) parts may be autoclaved.
After submerging parts in cleaning fluids, rinse thoroughly with distilled water. It is recommended to blow residual moisture from the orifices with compressed air. Then allow parts to dry completely before reassembling.
Port adapter should be reassembled following reassembly instructions below.
DISSASSMBLY: To disassemble the bypass port adaptor for cleaning, remove the stem and push connect elbow from the flat on the exterior of the adapter using an adjustable crescent wrench. Then loosen the two screws by turning them CCW with the provided 0.050” hex tool but do not remove screws completely. Insert the bladder insertion/removal tool through the inner diameter of the nipple until the shoulder of the tool contacts the nipple. There should be light friction felt as the tool slides into the rubber bladder.
Continue turning screws CCW with the hex tool until the screw-threads completely disengage from the mating threaded holes. Set the hex tool aside. Apply light lateral pressure to the insertion/removal tool and pull gently. The bladder assembly will come out with the insertion removal tool. Slide disassembled components off the tip of insertion/removal tool, Separating the bladder from the orifice plate and the orifice plate from the nipple. Leave the support collars around the bladder. The support collars should only be removed when the bladder is to be discarded and replaced.
BLADDER REPLACEMENT: The bladder should only be removed from the support collar when it is to be discarded and replaced. To remove, grasp the support collars in one hand and pull firmly on the rubber bladder with the other hand. Because the old bladder cannot be reused, one protruding end of the bladder may be cut with scissors to remove with ease.
The new bladder will be assembled into the two support collars one by one. Grasp the first support collar between the thumb and forefinger of the non-dominant hand. Grasp the tabbed end of the new bladder between the thumb and forefinger of the dominant hand. Pinch the bladder to fold the tabs in half lengthwise. This will make the tab easier to insert through the support collar. Push one folded tab through the support collar until it protrudes slightly from the other side. Regrip the protruding portion of the tab between the thumb and forefinger and pull gently. Regrip the rubber as close as possible to the support collar as the bladder gradually works its way through the ring. Repeat insertion steps for the second support collar. As the second support collar seats around the bladder, the second tab of the bladder will need to be coaxed through the ring. Pull this tab gently, taking care not to pinch it between the two support collars.
REASSEMBLY: To reassemble the valve, replace O-rings into O-ring grooves (if they were removed). Then tighten the 1/8” metal stem and push connect elbow into the flat on the exterior of the port adapter assembly with an adjustable crescent wrench.
Assemble the orifice plate to the base of nipple and clock the tabs on each part so they overlap with each other. Slide the nipple onto the insertion removal tool with the tabs facing away from the shoulder of the tool.
Slide the bladder (assembled with support collars) over the insertion/removal tool with the tabs of the bladder facing towards and aligned with the tabs of the orifice plate. Press the tabs of the bladder against the tabs of the orifice plate firmly, ensuring the orifices are visible in the hole through the bladder tabs as shown boxed in black. Grasping the support collar with the insertion/removal tool pointing up, load the screws into the screw holes as shown.
Grasp the head of the insertion removal tool with the dominant hand, using the index finger overlapping between the nipple and the shoulder of the insertion/removal tool to retain the bladder assembly against the tool.
Carry the assembly to the port adapter. Orient the tabs of the assembly to align with the tabbed pocket inside the port adapter. Slide the bladder assembly into the port adapter body, taking care not to twist the assembly during insertion. Press down firmly on the head of the insertion removal tool to aid in seating the assembly.
With the insertion removal tool still in place, used the provided 0.050” hex driver to tighten screws just shy of finger tight. At this point, screws will retain the assembly for removal of the insertion/removal tool. Remove the insertion/removal tool and tighten screws using the hex driver, alternating back between screws every three to four full turns of each screw.
As the screw tightens and compresses the soft silicone, resistance to turning the screws will increase gradually. At the point of full compression, the rigid orifice plate will bottom out against the stainless steel port adapter. This can be felt tactilely as a sharp and sudden rise in resistance to further screw rotation. Once both screws have reached this bottom-out condition, give each screw an additional 1/8” rotation and set tools aside. If possible, use a torque driver to tighten screws to 85 cN-m (12 oz-in).
Test reassembled port adapter in the provided test fixture prior to starting the next study.
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