4427493 Original Excavator Parts U Bolt for Hitachi ZX160LC-5A

The original U-bolt 4427493 is a specialized fastener for the Hitachi ZX160LC-5A (approximately 16 ton class) crawler excavator, and the universal number is its part number. The overall working weight of this model is approximately 16200kg, equipped with engines that comply with National III/IV emissions standards, and comes standard with the HIOS III intelligent hydraulic system. This U-bolt is commonly used to secure hydraulic oil tanks, fuel tanks, mufflers, or hydraulic pipeline brackets. Its U-shaped curvature, thread specifications (such as M12, M14, M16, etc.), and foot length dimensions are precisely matched with the frame or component mounting seat of ZX160LC-5A, ensuring that it can firmly clamp tubular or sheet-like components even under severe vibration working conditions of excavators. When ordering, it is necessary to check the factory number and part number 4427493 of the host. This part may also be compatible with similar models such as ZX160LC-3 and ZX180LC-5A, but it is recommended to follow the original parts catalog to avoid installation mismatch or insufficient preload due to size deviation.

This product is made of high-strength alloy steel (commonly 35CrMo or 42CrMo) through hot forging, and after quenching and tempering heat treatment, the hardness reaches 32-39HRC, the strength grade is 10.9 or 12.9, and the tensile strength is not less than 1040 MPa, with excellent shear and fatigue resistance. The U-shaped part is bent by the mold, and the inner arc radius is consistent with the outer diameter of the fixed component to ensure full circumferential fit; Both ends of the car are designed with metric triangular threads (coarse or fine), with a thread tolerance of 6g. The surface is often treated with Dacromet or hot-dip galvanizing, and can withstand salt spray corrosion for more than 500 hours. We provide original hexagonal nuts (GB6170 standard) and flat washers as a matching item. The nuts may come with nylon inserts or flange faces to enhance the anti loosening effect. As an original factory component, its dimensional tolerance, coating thickness, and load-bearing capacity have all passed the bench vibration test and comply with the JB/ZQ4321-2006 "U-bolt" standard. It can maintain its fastening force for a long time in an environment of -30 ℃ to 120 ℃.

Before installation, it is necessary to thoroughly clean the bolts, nuts, and installation surfaces, remove oil stains and burrs, and check whether the threads are intact. It is necessary to use a torque wrench to cross tighten according to the torque value specified in the Hitachi maintenance manual (for example, the torque of the ZX160LC-5A fuel tank fixing bolt is about 100-160N · m), and it is strictly prohibited to tighten beyond the torque to avoid bolt tension or thread slippage. Every 250 hours of daily work, U-bolts should be checked for looseness, cracks, or rust, especially in bent parts and thread roots; If the pre tightening force is found to decrease, it needs to be re tightened in a timely manner. After long-term water immersion operations, it is necessary to clean the soil on the surface of the bolts and apply anti rust grease.