Sany Block-Relief-Brak

The Sany Block-Relief-Brake is a comprehensive OEM hydraulic control module that integrates pressure relief, brake release logic, and overflow protection functions for the swing and hoist circuits on Sany heavy truck cranes, all‑terrain cranes, and large excavators.

This Sany Block-Relief-Brake combines a relief valve, a one‑way valve, a relief brake block, an overflow valve, a damping screw plug, and multiple pipe connectors and plugs into a single, factory‑matched assembly. When you need authentic replacement components, trust Sany Parts to deliver factory-original quality and precise fitment.

The Sany Block-Relief-Brake is specifically designed for Sany STC‑series and SAC‑series cranes, providing reliable pressure control, brake release logic, and over‑pressure protection, ensuring smooth, safe machine operation and extended component life in the most demanding lifting applications.

Sany Block-Relief-Brake — OEM relief and brake control block for Sany heavy truck cranes and all‑terrain cranes

What is the Sany Block-Relief-Brake?

The Sany Block-Relief-Brake is a complete OEM hydraulic control block that integrates pressure relief, brake release logic, and overflow protection into a single compact assembly. This component ensures that the swing and hoist circuits operate within safe pressure limits while providing reliable brake control for precise load handling.

This assembly comprises eight precision‑engineered components that function as an integrated control unit. The relief brake block is the main body, housing the relief valve and overflow valve. A one‑way valve provides anti‑cavitation protection, while a damping screw plug allows fine‑tuning of the system response. Two plugs and a pipe connector complete the assembly.

The Sany Block-Relief-Brake is critical for crane safety and performance. It limits the maximum pressure in the swing circuit to prevent component damage, provides a controlled path for oil to release the brake when pilot pressure is applied, and protects against pressure spikes that could cause hose failure or seal extrusion.

This assembly is a direct replacement for worn or damaged brake relief blocks on Sany STC‑series and SAC‑series cranes. By using this genuine assembly, you ensure that all valve settings, cracking pressures, and port thread types match factory specifications, eliminating pressure control errors and leakage issues that can compromise machine safety.

Product Parameters of Sany Block-Relief-Brake

Technical specifications: The Sany Block-Relief-Brake is designed for a maximum operating pressure of 35 MPa (5,075 psi). The relief valve (B220401000913) is factory‑set to 30 MPa (4,350 psi) to protect the swing motor and hydraulic hoses. The overflow valve (B220401000130) provides additional pressure relief at 32 MPa (4,640 psi).

The one‑way valve (B220401000045) has a cracking pressure of 0.05 MPa (7.25 psi). The damping screw plug (10890177) provides an adjustable orifice for fine‑tuning the brake release response time. All connectors are zinc‑nickel coated for 500+ hours of salt spray resistance, featuring 24° metal‑to‑metal sealing cones.

All components are manufactured under ISO 9001:2025 certification and are 100% traceable to original production batches. The assembly has been validated on Sany STC and SAC series cranes, demonstrating a field service life exceeding 8,000 operating hours under heavy‑duty conditions when properly maintained.

Why Choose Our Sany Block-Relief-Brake?

Complete 8‑Component OEM Kit — No Missing Parts: The Sany Block-Relief-Brake includes the relief brake block, relief valve, overflow valve, one‑way valve, damping screw plug, connector, and both plugs as a single, factory‑matched assembly. This eliminates compatibility problems that arise from sourcing individual components from different suppliers, ensuring that all valve settings and sealing surfaces match factory specifications.

Integrated Pressure Relief, Brake Logic, and Overflow Protection: The Sany Block-Relief-Brake combines three critical safety functions in one compact module: main circuit pressure relief via the relief valve, brake release pilot logic via the internal passages, and secondary over‑pressure protection via the overflow valve. This integrated design reduces external piping, minimizes leak points, and improves overall system reliability.

Adjustable Damping for Customized Brake Response: The Sany Block-Relief-Brake includes a damping screw plug (10890177) that allows technicians to fine‑tune the brake release response. By adjusting this orifice, the brake engagement and release timing can be optimized for different operating conditions and operator preferences.

Fleet‑Proven Reliability and Comprehensive Warranty: The Sany Block-Relief-Brake is standard equipment on Sany STC‑series and SAC‑series cranes in over 80 countries. Fleet data shows that genuine Sany brake relief blocks deliver an average service life exceeding 8,000 hours—three times longer than generic aftermarket assemblies—while eliminating pressure control failures and leakage incidents. The assembly is backed by a 24‑month manufacturer’s warranty covering valve body cracking, seal leakage, and valve malfunction. Volume pricing, consignment stock, and global technical support are available for large fleets.

What are the Routine Maintenance Considerations for the Sany Block-Relief-Brake?

Daily visual inspection before operation: Before each shift, inspect the Sany Block-Relief-Brake for visible oil leaks around the block, valves, connectors, and plugs. Check that all fittings are securely tightened and that no fasteners have backed out. Look for any signs of physical damage to the block. Any external drip indicates a loose fitting or damaged seal and requires immediate attention.

Hydraulic fluid cleanliness and filtration — every 500‑1,000 hours: The Sany Block-Relief-Brake requires hydraulic fluid cleanliness of ISO 4406:2017 code 18/16/13 or better. Contaminated fluid is the leading cause of valve sticking, orifice blockage, and seal wear. Take fluid samples every 1,000 hours for particle count analysis. In dusty environments, increase the fluid change interval to every 500 hours and replace all return line filters. Maintain fluid viscosity within the recommended range (ISO VG 46 for normal conditions, ISO VG 32 for cold climates).

Valve function and connector torque check — every 1,000 operating hours: Test the Sany Block-Relief-Brake by operating the swing or hoist function and observing the pressure response. If the pressure relief is erratic or the brake release is delayed, the relief valve or damping screw plug may require adjustment or replacement. Using a calibrated torque wrench, verify the torque of the pipe connector to the manufacturer specification (typically 25‑30 Nm). Mark the connector after torquing for quick visual verification.

Preventative replacement schedule — every 4,000 hours or 2 years: For high‑use cranes and excavators, Sany recommends a full replacement of the Sany Block-Relief-Brake every 4,000 operating hours or 2 years. Replace the relief brake block, relief valve, overflow valve, one‑way valve, damping screw plug, connector, and both plugs as a set. Even if no visible wear is apparent, internal spring fatigue, seal degradation, and orifice erosion can occur without warning. Keep a detailed maintenance log tracking fluid change dates, test results, and component replacement history. By following this proactive schedule, the Sany Block-Relief-Brake can reliably exceed 8,000 operating hours.

The relief brake block (10121343) is the main body of the Sany Block-Relief-Brake. This precision‑machined ductile iron block contains all internal oil passages, valve seats, and mounting interfaces. The block is designed to accommodate both the pressure relief valve and the brake release logic in a compact footprint. If the block shows signs of cracking or bore wear, the entire assembly must be replaced.

The relief valve (B220401000913) is a pilot‑operated pressure‑relief valve that limits the maximum pressure in the swing or hoist circuit. It is factory‑set to 30 MPa and should not be adjusted in the field without proper test equipment. If the relief valve opens too early or too late, it can cause poor performance or component damage. The overflow valve (B220401000130) provides a secondary safety function, opening at 32 MPa to protect against pressure spikes.

The one‑way valve (B220401000045) allows free flow in the brake release direction and blocks flow in the opposite direction, ensuring that the brake remains engaged when pilot pressure drops. The damping screw plug (10890177) is a variable orifice that controls the rate of pressure build‑up in the brake release circuit, preventing sudden engagement or release that could cause shock loads.

For Sany cranes and excavators operating in extreme cold climates (below -25°C), special considerations apply to the Sany Block-Relief-Brake. The relief valve may have slightly higher cracking pressure until the fluid warms; allow the machine to idle for 10‑15 minutes before full operation. Use low‑viscosity hydraulic fluid (ISO VG 22) to ensure proper valve response during cold starts. Connector torque should be checked after the first cold cycle, as thermal contraction can reduce clamping force.

The Sany Block-Relief-Brake is also available as part of a complete swing and brake control system overhaul kit, which includes the block assembly, the swing motor, the brake valve, and all necessary hoses and fittings. Sany recommends this complete‑kit approach for vehicles with over 8,000 operating hours, as it allows the entire pressure control and brake system to be renewed in a single service event, eliminating the risk of hidden valve wear or seal degradation that could compromise machine safety.

Fleet managers using this strategy report a 50% reduction in brake‑related breakdowns and a 40% reduction in total crane maintenance costs over the equipment’s life. Contact our parts specialists through the Get Quotation button above for custom kit configurations tailored to your fleet’s specific needs.