Additional Charging Information.   1: Accumulators as shipped from the factory contain neither a nitrogen gas charge or oil under pressure. However, there may be a very low nitrogen charge left in the accumulator from the factory test. 2: DO NOT use any gas other than DRY NITROGEN. The use of high pressure air or other gases can be DANGEROUS!. 3: Standard accumulators are for use with petroleum base fluids. If you are using fluids other than a petroleum base fluid, the distributor of Wilkes and McLean, Ltd. should be contacted to determine if the standard accumulator is compatible with your fluid. 4: The standard accumulator is rated for a maximum working pressure of 3000 P.S.I. DO NOT exceed this maximum pressure rating. 5: The standard accumulator is designed to operate in a temperature range from a MINUS (-) 0 degrees F. TO PLUS (+) 158 degrees F. with petroleum based fluids. Bladders for wider temperature ranges and special fluids are available. 6: DO NOT disassemble any accumulator without first making certain that the gas charge has been completely vented. 7: DO NOT weld or in any way machine the accumulator shell. This can weaken or damage the accumulator shell. In the case of A.S.M.E. coded accumulators, this can void the A.S.M.E. certification. 8: The accumulator may be mounted either vertically or horizontally. A loss of approximately 5% in efficiency or discharge volume will be experienced when mounting the accumulator horizontally. Consideration should also be given to the cleanliness of the system. If the accumulator is mounted horizontally, it could become a trap for the contaminants in the system. CHARGING THE ACCUMULATOR WITH NITROGEN Prior to charging the accumulator with nitrogen, it is advisable to pour some oil into the accumulator oil port and tilt the accumulator to allow the oil to coat the I.D. of the accumulator shell. This will provide the initial lubrication between the bladder and the shell. The accumulator can be charged before or after it has been installed in the system. TO PROPERLY CHARGE THE ACCUMULATOR, YOU WILL NEED THE COMPONENTS SHOWN BELOW.  NITROGEN PRECHARGE PRESSURE The usual nitrogen precharge pressure is 80% of the minimum circuit pressure. As this nitrogen precharge percentage increases, more volume will be displaced from the accumulator, However, it should not be increased above 90% on vertical installations or 85% on horizontal installations. If these percentages are exceeded then bladder life is reduced. Bladder damage can occur if the nitrogen precharge pressure falls below 35% of the maximum working pressure. For constant monitoring of nitrogen pressure or for accumulators used with a nitrogen back up bottle, the top of the accumulator is drilled and tapped with a 1/2" N.P.T. port and the Dynac charging valve parts are eliminated. Piping from this port goes to either a remote pressure monitoring and charging valve or to back up nitrogen bottles. If necessary, larger ports are available at the top of the accumulator. However, if excessive nitrogen is exhausted from the accumulator then a Transfer Barrier Tube should be used at the top of the accumulator to prevent bladder extrusion You are now ready to charge the accumulator. The following step-by-step procedure should be used: 1: Make certain the bleeder valve is closed. 2: Turn the core opening handle of the 3-way gas charging valve clockwise to depress the stem in the gas valve body. 3: Open the valve in the top of the nitrogen bottle very slightly to allow a small flow of nitrogen into the accumulator. It is highly recommended that a regulator be used on the top of the nitrogen bottle. In this case, you would then open the regulator slightly to allow a small flow of nitrogen into the accumulator. If the nitrogen is allowed to flow too rapidly into the accumulator, it can DAMAGE THE BLADDER. Watch the pressure gauges on the top of the accumulator and the nitrogen bottle. Allow this to stabilize between 120 P.S.I. and 200 P.S.I. At this point, the bladder will be fully expanded and you may now proceed to bring the nitrogen charge up to your requirement. 4: Once you have reached your required precharge pressure, allow the system to stabilize for 5 to 10 minutes. Usually the gas pressure will drop slightly due to molecular movement of the gas. If the gas pressure does drop slightly, add enough gas to bring the system up to your desired precharge. 5: For most systems a gas charge pressure of 80% of minimum system pressure is recommended. For systems where the accumulator is being utilized as a shock or pulsation dampener, a precharge pressure of 65% of minimum system pressure is recommended. WARNING: DO NOT EXCEED A COMPRESSION RATIO OF MORE THAN 5 TO 1. BY COMPRESSION RATIO, WE MEAN THE PRESSURE RANGE BETWEEN MINIMUM AND MAXIMUM SYSTEM PRESSURE. IF THIS FIGURE IS EXCEEDED, IT WILL RESULT IN DAMAGE TO THE ACCUMULATOR BLADDER. 6: When the gas charging procedure is completed, turn the core opening handle counter clockwise to allow the gas valve in the accumulator top to seat. Next, close the valve on the top of the nitrogen bottle. Bleed the pressure in the charging hose by opening the bleeder valve on the gas charging 3-way valve. 7: Remove the 3-way gas charging valve from the top of the accumulator. It is always a good practice to check for leakage after the charging procedures have been completed. 8: Replace the gas valve guard and other components which you removed prior to the charging procedure. 9: DO NOT leave the 3-way charging valve attached to the accumulator. The 3-way valve is not intended to be a permanent leak proof connection. The gas valve guard helps serve this purpose. 10: NEVER start the hydraulic pump before charging the accumulator. The pump pressure tends to force the bladder up into the charging valve at the top of the accumulator and can damage the bladder. Shown are the two styles of top assemblies for the accumulator. The valve is identical for the complete range of accumulator sizes. To install the 3-way gas charging valve, remove the gas valve guard, No. 3 on sizes R-210-01D through R-210-10d. On sizes H-230-20D through H-230-60D and N-210-120 and 160, remove parts No. 1, gas valve dirt cover. Install a pressure gauge in the gauge port of the 3-Way gas charging valve. Next, thread the 3-way gas charging valve onto the gas valve body located in the top cover assembly of the accumulator. Open the bleeder valve by turning it counter clockwise. Now, turn the core opening handle clockwise to depress the stem in the gas valve body and release any pressure which may be in the bladder of the accumulator. Close the bleeder valve by turning it clockwise and turn the core opening handle counterclockwise to allow the stem in the gas valve body to properly seat.