The hydraulic valve block manufacturer introduces the planning and processing of hydraulic valve blocks to you

The hydraulic valve block manufacturer introduces the planning and processing of hydraulic valve blocks to you

For a hydraulic station or hydraulic system, the planning and processing of integrated valve blocks are of great significance. So, what should be noted in the planning and processing of hydraulic integrated valve blocks?

First of all, understand the schematic diagram and determine which components to integrate on the integrated circuit. Next, it's time to select components. Since it's an integrated circuit, of course, cartridge valves and plate valves should be the main choices. Arrange the oil circuit structure reasonably according to the component samples, and the interface dimensions must be correct. A satisfactory thickness should be maintained between the channels to prevent the oil passage from being penetrated. Appropriate inclined holes and process through holes can be drilled. Of course, choosing 3D software for planning can visually view and verify whether the integrated circuit planning is reasonable.

When planning a valve block, it can be roughly divided into the following steps: material selection, processing and heat treatment, deburring and cleaning, surface rust prevention treatment, and experimentation.

1. Material selection

Different materials determine different pressure grades. The primary principle is to select materials reasonably based on the applied pressure. Generally speaking, the following principles should be followed:

When P<21MPa, the hydraulic valve block can be made of aluminum alloy forgings or 45 steel plate materials.

When P≥21MPa, the hydraulic valve block can be made of No. 35 forged steel. After forging, normalizing and tempering treatment is carried out before machining (for general high-pressure valve blocks, flaw detection, machining and heat treatment are often carried out in a cycle).

2. Planning and processing of valve blocks

When planning the valve block, the initial thickness of the valve block is set at five times the larger diameter, and then it is gradually reduced according to the specific design. When planning the channels, the holes should be reasonably arranged, and deep holes, inclined holes and process holes should be minimized as much as possible. Large flow channels should be arranged first, followed by pilot oil channels. The safety wall thickness between each hole should not be less than 3 to 5mm. The deflection of the drill bit within the allowable range should also be considered, and the distance between adjacent holes should be appropriately increased. The flow rate of hydraulic oil in the channel must not exceed 12m/s, and the return oil channel should be 20-40% larger than the intake oil channel. The oil inlet, working port and control port of the valve block need to be processed with pressure measurement ports. Each valve port should be engraved with a number. For valve blocks with larger mass, lifting screw ports are required.

After the valve block planning is completed, processing is carried out. The processing technology is roughly as follows

(1) Pretreatment before processing. The materials for processing valve blocks must ensure a dense internal arrangement without any defects such as interlayers or sand holes. Before processing, the blank should be inspected for defects. Cast iron blocks and larger steel blocks should undergo aging treatment and pre-treatment before processing.

(2) Material cutting. Generally, at least 2mm or more of machining allowance should be left on each side.

(3) Mill the shape. Mill six sides of the valve block, leaving a rough grinding allowance of 0.2 to 0.4mm on each side.

(4) Rough grinding. Roughly grind 6 surfaces of the valve block, leaving a fine grinding allowance of 0.05 to 0.08mm on each side to ensure that the parallelism of each pair of corresponding surfaces is less than 0.03mm and the straightness of two adjacent surfaces is less than 0.05mm.

(5) Draw a line. Where conditions permit, it can be completed directly with a center drill on a CNC drilling machine.