ZQ 400 Gearbox (Size 400) – 75mm Output Shaft | 3-5 Ton Load Capacity

If the ZQ 350 series is still not enough load for your system, the ZQ 400 speed reducer gearbox is the perfect upgrade solution. Belonging to the ZQ 400 load capacity gearbox category, it possesses a massive size and superior shock load capacity, often referred to as “indestructible” in steel rolling and stone mining plants.

General Design of the ZQ Gearbox

The ZQ gearbox features the signature design style of the heavy-duty line, focusing maximally on mechanical durability and stability:

• Protective housing: Cast in one piece from high-quality alloy cast iron, with a very thick wall to resist strong impact forces and continuous vibration environments.
• Base: The base of the ZQ 400 is specially reinforced, extra thick, and much wider compared to the ZQ 350, ensuring a secure grip and preventing shifting when connected to large-capacity motors.
• Style: Classic horizontal rectangular wedge design, natural heat dissipation through the cast iron housing surface, easy to install and connect with pulley systems or couplings.

Structure of the ZQ 400 Heavy-Duty Gearbox

Inside the housing, the ZQ 400 features a precision, high-load mechanical transmission mechanism:

• Gear system: Uses helical gear pairs machined from super-hard alloy steel (heat-treated and carburized). Helical teeth ensure smooth meshing, reduce noise, and withstand extreme torque.
• Transmission shaft: Includes primary shaft (input shaft) and secondary shaft (output shaft). The output shaft has a large size of up to 75mm to ensure it does not bend or crack when pulling heavy loads (such as 3-6 ton winches).
• Bearings: Equipped with heavy-duty roller or tapered roller bearings at both ends of the shaft journals, helping maintain continuous smooth movement.
• Sealing system: High-quality oil seals and heat-resistant gaskets are installed at the shaft ends to prevent oil leakage and dust from entering the gear chamber.

Technical Specifications of the ZQ 400 Gearbox (Size 400)

The ZQ 400 is significantly larger than the ZQ 350, especially the output shaft and the very thickly reinforced base. This line is suitable for installation with 11kW (15HP), 15kW (20HP), or 18.5kW (25HP) motors – Speed 1450 rpm. Below are the standard specifications:

Practical Applications of the ZQ 400 Gearbox

ZQ 400 Gearbox commonly appears in large-scale production lines:

• Winch systems: Coal cart winches, marine slipway winches (pulling capacity 3-6 tons).
• Steel/sheet rolling machines: Acting as primary gearbox for thick purlin and sheet rolling machines.
• Stone crushers: Driving large rock conveyors in mining quarries.
• Double-girder overhead cranes: Used for the traveling mechanism of 10-ton and 20-ton overhead cranes.

Instructions for Adding Oil to the ZQ Gearbox

With a large chamber capacity (4.0 – 5.0 liters), proper lubrication directly determines the lifespan of the ZQ 400. Below are the operational steps:

• Determine position: Locate the oil filling plug (usually located at the top of the gearbox) and the oil sight glass (oil level gauge) located on the side of the housing.
• Choose lubricating oil: Use specialized industrial oils for extreme pressure gears (e.g., mineral-based gear oil with viscosity ISO VG 220 or 320).
• Proceed to add oil: Open the filling plug and slowly pour in the oil. Observe the oil level through the sight glass while pouring.
• Check level: Stop when the oil level reaches the middle mark (or covers about 1/3 to 1/2 of the volume of the largest internal gear). Note: Do not overfill to avoid foaming and temperature increase when the gears agitate the oil at high speed.
• Maintenance: Change the oil for the first time after about 500 initial operating hours to remove excess metal particles, and subsequently change every 2500 – 3000 hours.

The ZQ 400 gearbox is the perfect piece for steel rolling mills, mineral extraction plants, and lifting winch systems that require the highest durability. With super-hard steel gear construction, load-bearing cast iron housing, and flexible connection capabilities, this equipment ensures your system always operates stably against all shock loads.

To observe in detail every design detail, mechanical disassembly method, and the practical operation of the product, please watch our compilation video and the most detailed gearbox video on our channel.

Warranty, Shipping, and Commitment Policy at Thanh Thai Motor

When purchasing gearboxes at Thanh Thai Motor, you will receive benefits such as:

Warranty up to 24 months

Gearbox products at Thanh Thai Motor are covered by a genuine warranty for up to 24 months. Customers can be completely confident in using them with a clear, transparent, and prompt after-sales policy.

Nationwide Delivery

We support fast delivery to all provinces and cities nationwide. Wherever you are, products are guaranteed to arrive on time and safely.

Products meeting European quality standards with German technology

Gearboxes at Thanh Thai Motor are manufactured using advanced German technology, meeting European quality standards. Ensuring high durability and stable operation for extended periods.

Competitive prices, good discounts for dealers and bulk customers

Reasonable prices, many attractive offers for wholesale buyers and distribution agents. The more you buy, the higher the discount – optimizing profits for customers.

Full certification documents: CO, CQ,...

Each product comes with full Certificate of Origin (CO) and Certificate of Quality (CQ). This provides assurance for customers when using them in projects or constructions requiring technical documentation.

Contact for Purchase

Do you need advice on choosing the right gearbox for your needs? Contact Thanh Thai Motor immediately using the methods below:

• WhatsApp: +84966596219
• Email: codienthanhthai@gmail.com