When infected with SARS-CoV-2, and if the course of the infection worsens, intensive care physicians need pictures of the condition of the patient's lungs quickly. Mobile X-ray devices are the most effective medical equipment for diagnostic purposes. In order to make time-critical work with these high-tech aids fast, safe and easy, an international manufacturer relies on gas springs from ACE Stoßdämpfer GmbH.

The central Chinese metropolis of Wuhan with its over 11 million inhabitants was the first center of the spread of the novel corona virus. As the infection rates became more and more exponential, the crisis managers implemented an unprecedented lockdown and reacted by building completely new hospitals within a few days. The logistical challenge included not only the engineering and work on site but also the planning, production and provision of the necessary medical services in the hospitals. Due to the short time available, the criteria to be met by doctors and nurses as well as medical equipment providers and their suppliers were extremely high. This also applied to Beijing Wandong Medical Technology Co. Ltd. The specialists in medical imaging equipment are known worldwide under the Wandong brand name and are successfully represented with their solutions in over 70 countries and regions. As such, thanks to their networked and intelligent manufacturing and service processes, they can also deliver large quantities in a short time. With the urgently needed digital mobile X-ray devices, however, it became apparent that additional support on the part of the supplier was necessary with regard to the rapid supply of industrial gas springs.

ACE confirmed as first choice also for delivery capability

Mobile X-ray devices for digital radiography (DR) meet the special requirements of intensive care units, emergency rooms and pneumology departments. As the outbreak of the corona pandemic shows, this now also applies to the sometimes more than turbulent processes in special quarantine zones. Mobile DR devices are not only stable and reliable and their images are as good as those of fixed DR devices, they also help medical staff to drastically reduce the radiation exposure for patients and themselves compared to older X-ray technologies. In order to further increase the safety for users and patients, the involvement of a partner for industrial gas springs was aimed at reducing the risks arising from the mechanics of the device: "Even when designing the mobile unit long before the current developments, we were already looking for a reliable solution to support the beam arm of the digital X-ray device," explains Lu Fei, one of the project managers at Wandong. Quality and reliability of the gas spring are of crucial importance during mobile X-ray operation. This is owing to the fact that the medical personnel has to lift the arm supported by the gas springs to a certain control position which can vary each time according to the patient's anatomy. Since there is a theoretical risk that the beam arm can drop, the gas spring must maintain its holding force.

When the outbreak of the corona pandemic in Wuhan was at its peak and fast, reliable lung diagnostics became increasingly important, Wandong was able to come up with a solution immediately. Lu Fei looks back: "The quick reaction of our production department was also possible because we had already explored the market for gas spring solutions and tested products from various manufacturers based on the available design data. Even at this stage, our first choice was a solution from ACE Stoßdämpfer GmbH. When the company was able to promise us to deliver several hundred units of consistent quality in the shortest possible time, the order went out."

Although ACE Stoßdämpfer is located in Langenfeld, Germany, it also operates as a company of the STABILUS Group with its own subsidiary and sales partners in China, and is well known by engineers and product designers for its wide range of solutions in the fields of automation, motion and vibration control as well as for their safety products. Industrial gas springs provided by ACE are not only part of the motion control segment, but are also characterized by their great variety. They are available in both push and pull types, they are designed for particularly hot or cold environments, and they also come as stainless steel versions when particularly strict hygiene regulations have to be met, such as in the medical or food industry. In addition, models made of stainless steel are also a good choice when the respective construction is in the public eye, as they are perceived to be visually more attractive. In this particular case, however, the main reasons for the order were the high quality made in Germany and the quick availability. "We have made every effort to help and to ensure that our products reach the equipment manufacturers as soon as possible. Faced with the severe epidemic, every minute and every second counted," Dr. Tian Xuefeng, Managing Director of STABILUS (Jiangsu) Co., Ltd. summarizes the situation on site on behalf of ACE.

Gas springs save space and provide energy

While the weight of the beam arm in the mobile X-ray unit is 10 kg, the X-ray device mounted to it weighs 30 kg. Given the total weight, the starting point and opening angle had to be taken into account when selecting the right gas spring as well. While the maximum opening angle should be 130 degrees, the starting point is 0 degrees. Since the gas springs are installed inside the beam arm for reasons of ergonomics and space, it also explains why stainless steel versions could be dispensed with in this case, despite the high sensitivity in terms of hygiene regulations.

The selected ACE pull type GZ-28-450 gas springs also have a positive effect on user-friendliness in other respects: On the one hand, they reliably hold the beam arm in the final position, and on the other hand, they support the muscle power during raising and lowering. In doing so, they work in the opposite way to the principle of gas push type springs. This means that the gas pressure in the cylinder draws the piston rod in and, when moving the arm, supports the manual force required for a controlled motion. Like all solutions provided by ACE, the gas springs also offer maximum service life, in this case thanks to solid chrome-plated piston rods and integrated sliding bearings. With these maintenance-free and ready-to-install components, designers can choose between body diameters from 15 mm to 40 mm and traction forces from 40 N to 5,000 N. In the mobile X-ray solution offered by Wandong, models with an outer diameter of 28 mm and a maximum force of 1,200 N at a stroke length of 450 mm work reliably. An additional advantage of the ACE solutions: No matter what the stroke length, the traction force can be subsequently adjusted via a valve by letting gas escape or by filling it with the filling case available from ACE, depending on the application.

Both at peak times of the crisis in the newly built hospitals in Wuhan and in the calmer clinical routine afterwards, the industrial gas springs from ACE have lived up to their reputation as problem solvers. The mechanical assistants have increased the safety and user-friendliness of Wandong's mobile digital X-ray units. This literally relieves the medical staff to concentrate on their actual tasks, not only in the uniquely hectic times of the pandemic: Saving lives, fighting COVID-19.

The emergency hospitals Huoshenshan and Leishenshan in Wuhan were built within a few days around the clock and each has 1,000 beds for COVID-19 patients and up to 30 intensive care units.

When life is at stake, it must be possible to bring an X-ray system directly to the patient to avoid waiting times in crowded hospitals. Space-saving, complete digital solutions enable X-ray of extremities as well as thorax, spine, abdomen and pelvis.

Beijing Wandong Medical Technology Co Ltd, a Chinese imaging systems specialist, proves to be a reliable supplier of urgently needed digital mobile X-ray units worldwide not only during the corona pandemic.

The digital mobile X-ray units from Wandong are extremely compact. Transport and operation can be carried out by a single professional. Necessary components such as X-ray detector, X-ray generator, image processor and software are combined in the unit.

Pull type GZ-28-450 industrial gas springs provided by ACE are key components for compactness and operating safety in the beam arm of the Wandong X-ray unit.

Even before the corona pandemic at Wandong, ACE had already established itself as the most efficient manufacturer of pull type gas springs in tests and confirmed this position during the crisis through exemplary delivery readiness and quality.

Picture credits
Pictures 1, 2, 5, 6: ACE Stoßdämpfer GmbH
Pictures 3 and 4: Beijing Wandong Medical Technology Co. Ltd