120 Type Air Distribution Valve Chinese Standard Air Brake for Railway Wagons

120 Type Air Distribution Valve Chinese Standard Air Brake for Railway Wagons

1. Brief introductions:

The primary braking system for freight wagons on Chinese railways is the 120 type air brake. This system operates in five different modes: inflation release, decelerating inflation release, service braking, maintaining brake pressure, and emergency braking.The core of this air brake system is the 120 type control valve, which includes essential components such as the main valve, middle body, semi-release valve, and emergency valve. This control valve is securely attached to the under frame using bolts and nuts that go through the holes in the middle body.

2. Main parameters:

3. Main features of 120 air control valve:

• Mechanism of Two Pressures: The primary control mechanism functions based on the difference between two pressures: the pressure from the auxiliary air cylinder and that from the train pipeline.
• Direct Action Mode: When pressurized, the main control mechanism links the brake pipe with the auxiliary air cylinder and allows the brake cylinder to connect with the outside air. In contrast, during decompression, it directly connects the auxiliary air cylinder to the brake cylinder.
• The main control mechanism features a structure made of a rubber membrane plate alongside a metal slide valve.
• The service brake operates separately from the emergency brake.
• There is a reduction in two stages.
• Two sections activate during the emergency brake action.
• There is a quick release.

4. Application photo: