1) DH220LC--3, DH280LC- 3, DH330LC--3, DH200W--3 excavator, using DX22(28) type main control valve produced by Toshiba (TOSHI-BA) company, with priority function of boom, such as As shown in Figure 16-17.
2) The large-character DH0L.C-m crawler excavator uses the UDX36 main control valve produced by Toshiba Corporation, as shown in Figure 16-18a, and its boom priority valve structure is shown in Figure 16-18b. When the loading mode and the lifting mode are selected, Pur = 2.9MPa; when the land preparation mode is selected, Pa = 0MPa.
3) The structure of the central valve block of UDX36 type main control valve is shown in Figure 16-19. Boom priority valves, swing priority valves, main relief valves, straight travel control valves and other auxiliary control functions are all installed on the central valve block.
