Bulletin hy14-1450-M1/us installation and Service Guide
Parker Hannifin Corporation
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- Điều hướng trang này:
- Filter Mainte- nance
| Parker Hannifin Corporation
Hydraulic Valve Division Elyria, Ohio, USA Pilot Operating Pressure The servovalve pilot stage operates on a relatively constant supply pressure. The pilot supply pressure should be approximately 450 psi. This pressure is established by placing an orifice between the servovalve supply pressure and the pilot valve. The orifice, part number 8100006, is located under the filter shown in Figure 3. Table 1 shows the color coding, the dash number and the servovalve supply pressure range recommended for each particu- lar orifice. It is important that the proper orifice be selected for the system pressure being applied to the servo. Improper orifice selection may over pressurize the pilot or result in very sluggish performance. To check or change the orifice, remove the filter as described in maintenance section. The top of the orifice should be visible when the filter is removed. It can be removed with a small blade screwdriver. The valve is set up to operate within a pressure range that can be verified by the dash number on the orifice. Should it be decided to change this pressure range, a suitable new orifice must be selected and then in- stalled as follows: 1. Lightly lubricate the new O-ring with hydraulic fluid. 2. Install the orifice in the pressure port and snug down with a straight-slot screwdriver. Care should be taken to select a screwdriver whose blade is not so wide that it will damage the threads in the housing. 3. Install the filter as described in the Filter Mainte- nance section. Use of Test Port The SAE-4 Test port is provided should a verification of pilot valve supply pressure be desired. To use this port, the SAE-4 plug must be removed, and replaced with a SAE-4 tube fitting and suitable pressure gage. When system supply pressure is applied to the servovalve, the pressure indicated on the pressure gage is pilot valve supply pressure. This pressure should be 350 to 600 psi with the valve at null. The test port may be also be used as an alternate pilot supply port by installing a blank supply orifice, -00 (red) in the valve body. The pilot supply pressure should be set between 450 psi and 500 psi. Special care must be taken to assure that this source is provided with a 25µm filter in it. It should be noted that the tank line from the pilot is joined inside the valve with the 2nd stage tank line. tải về 0.84 Mb. Chia sẻ với bạn bè của bạn:
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