With the vigorous development of the field of domestic medical devices, the requirements of plastic biocompatibility and the environmental protection problems of adhesives approved by medical grade have intensified. Many commonly used polymers, such as ABS, PC, PS, PP, PE and PTFE, are difficult to bond due to the particularity of their materials. Ultrasonic welding technology, as a favorite in the field of medical devices, is being widely used. The risks and challenges of plastic welding, It is often caused by improper welding process selection, ultrasonic weld design and testing methods, as well as part deformation and dimensional deviation. By taking step-by-step Troubleshooting Analysis and improvement measures, these problems can be reduced or eliminated.

The existing conventional instrument plastic shell assembly uses ultrasonic technology: disposable high-frequency electric knife and pen, disposable stapler (endoscopic linear cutting or tubular stapler), disposable cannula puncture device, disposable high-frequency ablation needle, cardiac blood circulation pump, etc. it should be noted that due to the particularity of the use scene of the instrument and the environmental impact in the processing and production process, When selecting the model again, we must consider it comprehensively

The disposable electric knife pen is composed of a knife head, a handle and a connecting cable. Scope of application this product is only an application part and needs to be used in conjunction with high-frequency surgical equipment to coagulate or cut biological tissues in surgery. The main function of ultrasonic welding machine in its production and assembly process is to press and weld the plastic handle. The traditional fastener firmness is not suitable for the use site, so the production process requirements are improved

Stapler is an alternative to manual suture in medicine. Its main working principle is to break or anastomose tissue with titanium nails, which is similar to stapler. The utility model comprises a shell, a central rod and a push tube. The central rod is arranged in the push tube. The front end of the central rod is equipped with a nail cover, and the rear end is connected with the adjustment knob at the tail of the shell through a screw. An excitation handle is arranged on the outer surface of the shell, which is movably connected with the shell through a hinge. The ultrasonic welding machine is equipped with a stapler plastic handle. The surface is free of damage and has good sealing after welding

The disposable cannula puncture device is composed of puncture cannula and puncture needle, and the auxiliary components include pneumoperitoneum needle, specimen bag and converter. The puncture sleeve is composed of sleeve, needle seat, choke valve and sealing cap. The welding end face of the upper cover of the valve body and the front end face of the valve body are sealed by ultrasonic welding process

To sum up, ultrasonic welding works by generating heat due to the mechanical vibration energy loss caused by the viscoelastic properties of polymers. The mold that produces ultrasonic vibration is called welding head. The contact surface between the welding head and the part must be parallel to the welding rib and the distance must be short (generally ＜ 6mm). In addition, sharp corners and thin cantilever structures shall be avoided in and near the welding area to prevent damage. Ultrasonic plastic welding is a more cost-effective scheme, which can provide consistent and high-strength welding without additional consumables. However, the following points should be noted according to the usage scenario:

Product welding accuracy requires accurate value

After welding, the levelness of the product is required, and the stability of the square column ultrasonic welding machine is higher

Whether there are requirements for frame shell folding in the clean workshop, plastic spraying treatment or stainless steel folding plate

With the increasing popularity of ultrasonic welding machine in the field of medical devices, higher requirements are put forward for its stability and welding mode selection, so it is necessary to give better play to its position in the medical field and make more contributions to the national health cause