1. Analysis of key performance parameters of residential elevators: reasonable configuration of load, speed and parking accuracy

In modern residential buildings, residential passenger elevators are an important tool for residents' daily travel. The reasonable configuration of their performance parameters directly affects the safety and convenience of use. The three key performance parameters of load, speed and parking accuracy are like the "three horses" of elevator operation. They need to be scientifically and reasonably configured by comprehensively considering multiple factors such as building type, user population, building height, etc.

(I) Load: The game between meeting demand and reserving redundancy

The load capacity of an elevator is one of the most basic performance parameters, which determines the number of passengers and the weight of cargo that the elevator can carry at one time. At present, the common load capacity specifications of residential elevators on the market are 400kg, 630kg, 800kg, 1000kg, etc. When determining the load capacity parameters, the number of residents and the frequency of use of the residence should be considered first. For ordinary high-rise residential buildings, if there are many households on each floor and the daily travel of residents is relatively concentrated, choosing an elevator with a larger load capacity can effectively reduce the waiting time of passengers and improve the user experience. For example, a high-rise residential building with 30 floors and 4 households on each floor, calculated based on 3-4 people per household, may have more residents using the elevator at the same time during peak hours. At this time, it is more appropriate to choose an elevator with a load capacity of 800kg or 1000kg, which can ensure that the elevator can accommodate more passengers during rush hours and avoid the waste of time caused by frequent round trips.

However, the load parameter is not the bigger the better. Excessive load means that the size of the elevator car will increase, which will increase the construction cost and space occupation of the elevator shaft on the one hand, and will also increase the energy consumption of the elevator during operation on the other hand. Therefore, when determining the load, a certain amount of redundant space needs to be reserved. The setting of redundant space is to deal with some special situations, such as residents carrying large furniture and decoration materials. Generally speaking, it is reasonable to reserve 10% - 20% of the load redundancy. For example, for a residence with a daily load demand of 800kg, choosing an elevator with a load capacity of 1000kg can not only meet daily use, but also provide convenience for residents to carry large items, and will not cause excessive waste of resources.

In addition, different regions have different requirements for the load capacity of residential elevators. In some old residential renovation projects, due to building structure and space limitations, it may not be possible to install large-load elevators. At this time, it is necessary to select appropriate smaller load specifications while meeting basic usage needs, and to optimize the elevator dispatching system to maximize usage efficiency.

(II) Speed: Adapt to the building height and usage scenario

The choice of elevator speed is closely related to the building height. Generally speaking, the higher the building height, the higher the elevator speed requirement. According to relevant specifications and actual use experience, for residential buildings with less than 30 floors, the elevator speed is usually selected from 1.0m/s to 1.75m/s; for residential buildings with 30 to 60 floors, the elevator speed can be selected from 1.75m/s to 2.5m/s; for super high-rise residential buildings with more than 60 floors, the elevator speed may need to reach more than 2.5m/s.

Taking a 30-story high-rise residential building as an example, if a lower speed 1.0m/s elevator is selected, the running time from the 1st floor to the 30th floor will be longer, which will seriously affect the travel efficiency of residents during peak hours. Choosing a speed of 1.75m/s can deliver passengers to the destination floor within a reasonable time, improving the travel experience. However, the increase in speed is not without cost. The faster the elevator speed, the higher the stability and safety requirements of the elevator system. At the same time, the noise and vibration generated during operation will also increase accordingly. Therefore, when choosing the elevator speed, in addition to considering the building height, it is also necessary to comprehensively evaluate the installation environment, equipment quality and subsequent maintenance costs of the elevator.

In some special usage scenarios, the choice of elevator speed also needs to be adjusted. For example, for senior apartments or retirement communities, since the residents are mainly elderly people, they have higher requirements for the smoothness and safety of elevator operation, and relatively low elevator speeds may be more popular. Even if the building is high, the elevator speed can be appropriately reduced, and the use needs can be met by increasing the number of elevators, etc., to ensure the comfort and sense of security of the elderly when taking the elevator.

(III) Docking accuracy: the technical support behind millimeter-level error

The docking accuracy is an important indicator to measure the operation quality of the elevator. It refers to the horizontal error between the elevator car sill and the floor sill. In residential elevators, the docking accuracy is usually required to be controlled within ±5mm, and some high-end residential elevators can even reach ±3mm. Accurate docking accuracy is not only related to the safety of passengers entering and exiting the elevator, but also affects the overall coordination between the elevator and the building.

In order to achieve high-precision parking, the elevator system adopts a variety of advanced technologies. The first is sensor technology. The elevator uses various sensors installed in the car and the shaft, such as photoelectric sensors, magnetic sensors, etc., to sense the position and operating status of the elevator in real time. These sensors can accurately measure the displacement and speed changes of the elevator, and transmit the data to the elevator control system to provide a basis for accurate parking. The second is the optimization of the control system. Modern elevators generally use advanced variable frequency speed regulation technology and intelligent control algorithms. Variable frequency speed regulation technology can adjust the speed of the motor in real time according to the load and operating status of the elevator, making the elevator more stable during the start, acceleration, deceleration and parking process; the intelligent control algorithm can plan the running trajectory of the elevator in advance according to the data fed back by the sensor to achieve accurate parking.

In addition, the installation quality and maintenance of the elevator guide rails also have an important impact on the docking accuracy. High-quality guide rail installation can ensure the linearity and stability of the elevator operation and reduce the docking error caused by guide rail deviation. Regular cleaning, lubrication and adjustment of the guide rails can ensure that the guide rails are always in good working condition and maintain the docking accuracy of the elevator. If the elevator's docking accuracy deviates, it will not only cause inconvenience to passengers entering and exiting the elevator, but may also cause safety hazards, such as passengers tripping and objects getting stuck. Therefore, in the selection and use of the elevator, the key performance parameter of docking accuracy must be highly valued.

2. Noise and vibration control: the core factor affecting living comfort

The noise and vibration generated during the operation of residential passenger elevators are one of the core factors affecting the comfort of residents. A quiet and stable elevator operation environment can create a comfortable and cozy living atmosphere for residents; on the contrary, excessive noise and vibration will seriously interfere with the daily life of residents and even affect their physical and mental health. Therefore, effective measures must be taken to control noise and vibration during the design, installation and use of residential elevators.

(I) The source and propagation path of noise

The noise during the operation of the elevator mainly comes from multiple aspects. The first is the noise generated by the elevator host. As the power source of the elevator, the host will generate mechanical noise and electromagnetic noise from the motor, reducer and other components during operation. Especially during the start-up and acceleration phases of the elevator, the rapid change in motor speed will cause the noise to increase. The second is the friction noise between the car and the guide rail. When the car runs on the guide rail, the contact and friction between the guide shoe and the guide rail will produce friction noise. If the surface of the guide rail is uneven or the guide shoe is severely worn, the noise will be more obvious. In addition, during the opening and closing process of the elevator door system, the operation of the door machine and the collision between the door and the door frame will also generate noise.

There are two main ways of noise transmission: air transmission and solid transmission. Air transmission refers to the direct transmission of noise to the surrounding environment through the air medium; solid transmission refers to the transmission of noise through solid structures such as the steel structure of the elevator and the wall of the building. This transmission method often causes the noise to spread farther and affect a wider range. For example, the noise generated by the elevator host is transmitted through the air, which will directly affect the residents on the floor where the elevator machine room is located and the adjacent floors; while through solid transmission, the noise may spread along the load-bearing structure of the building to other floors, causing interference to more residents.

(II) Technical measures for noise and vibration control

There are currently a variety of mature technical measures to control the source and propagation of noise. In terms of the elevator host, the use of low-noise motors and advanced reducer designs can effectively reduce the noise during the operation of the host. For example, some new permanent magnet synchronous motors, compared with traditional motors, have the characteristics of high efficiency and low noise, which can significantly reduce the mechanical noise and electromagnetic noise generated by the host. At the same time, when installing the host, use shock-absorbing pads, soundproof covers and other devices to isolate the host from the floor and walls of the machine room to block the propagation of noise.

For the friction noise between the car and the guide rail, on the one hand, the installation quality of the guide rail should be guaranteed, and the surface of the guide rail should be flat and smooth to reduce the friction between the guide shoe and the guide rail; on the other hand, new guide shoe materials can be used, such as elastic guide shoes, rolling guide shoes, etc. Elastic guide shoes have good buffering performance and can effectively absorb the vibration and noise during the operation of the car; rolling guide shoes replace sliding friction with rolling friction, which greatly reduces the friction noise.

In terms of elevator door systems, the control algorithm of the door machine is optimized to make the door opening and closing action smoother and softer, and reduce the collision noise between the door and the door frame. At the same time, installing sealing strips on the edges of the door can not only improve the sealing of the door, but also play a role in buffering and reducing noise.

In addition, during the building design phase, rationally planning the location of the elevator shaft can also help control noise and vibration. Placing the elevator shaft away from living spaces such as bedrooms and living rooms, or installing soundproof walls, shock-absorbing layers and other structures between the elevator shaft and living spaces can effectively reduce the impact of noise and vibration on residents' lives.

(III) Standards and testing: the key to ensuring noise reduction

In order to ensure that the noise and vibration control of residential elevators meet certain standards, the state and the industry have formulated relevant specifications and standards. For example, according to the "Technical Conditions for Elevators" (GB/T 10058), the noise value in the cabin of a passenger elevator during operation should not exceed 55dB (A) for elevators with a rated speed of no more than 2.5m/s; and should not exceed 60dB (A) for elevators with a rated speed of more than 2.5m/s. In the machine room, the noise value of the elevator during operation should not exceed 80dB (A).

After the elevator is installed, strict noise and vibration testing is required. During the testing process, professional noise measuring instruments are used to measure in multiple locations such as the car, the machine room, and the living space adjacent to the elevator shaft to ensure that the noise value meets the standard requirements. If the test results do not meet the standards, it is necessary to analyze the reasons and take corresponding improvement measures, such as further optimizing the shock absorption device and adjusting the guide rail gap, until the standards are met. Through strict standards and testing, the noise reduction effect of residential elevators can be effectively guaranteed, providing residents with a quiet and comfortable living environment.

3. Safety standards and regulations: Compliance points of GB 7588 and TSG T7007

The safe operation of residential passenger elevators is related to the safety of life and property of residents, so relevant safety standards and specifications must be strictly observed. In my country, the "Safety Code for Elevator Manufacturing and Installation" (GB 7588) and the "Rules for Elevator Supervision and Periodic Inspection - Traction and Forced Drive Elevators" (TSG T7007) are two important elevator safety regulations, which clearly stipulate the design, manufacturing, installation, inspection and maintenance of elevators. Understanding and mastering the compliance points of these standards and specifications is the key to ensuring the safe operation of residential elevators.

(I) GB 7588: Basic principles for elevator safety

GB 7588 is the most basic and important safety standard for my country's elevator industry. It covers all aspects of elevators from design to installation. In terms of mechanical safety of elevators, GB 7588 sets strict requirements for the design and manufacture of key components such as the load-bearing structure, suspension device, speed limiter, and safety clamp of elevators. For example, the suspension device of the elevator must have sufficient strength and reliability to withstand the rated load of the elevator and possible overload conditions; the speed limiter and safety clamp are important safety protection devices for the elevator. When the elevator running speed exceeds a certain percentage of the rated speed, the speed limiter will trigger the safety clamp to stop the elevator quickly to prevent the elevator from falling or overspeeding.

In terms of electrical safety, GB 7588 stipulates the insulation requirements, grounding protection measures and protection level of electrical equipment of elevator electrical systems. The electrical equipment of elevators must have good insulation performance to prevent leakage accidents; grounding protection measures can ensure that when electrical equipment fails, the current can be quickly conducted to the ground to ensure the safety of personnel. In addition, GB 7588 also makes detailed provisions for the emergency operating devices and alarm devices of elevators, requiring elevators to be equipped with emergency lighting, alarm devices, etc., so that passengers can get rescue in time when the elevator fails.

(II) TSG T7007: Guidelines for the inspection and maintenance of elevators

TSG T7007 mainly focuses on the supervisory inspection and periodic inspection of elevators, which provides an effective quality assurance and supervision mechanism for the safe operation of elevators. After the installation of the elevator is completed, it must be supervised and inspected in accordance with the requirements of TSG T7007, and can only be put into use after passing the inspection. The supervisory inspection includes inspections of the installation quality, safety protection devices, electrical systems and other aspects of the elevator to ensure that the installation of the elevator complies with the requirements of relevant standards such as GB 7588.

After the elevator is put into use, it needs to be inspected regularly. According to TSG T7007, elevators in use should be inspected regularly at least once a year. The purpose of regular inspection is to promptly discover potential safety hazards that may occur during the use of the elevator and to ensure that the performance indicators and safety protection devices of the elevator are in good working condition. The inspection content includes functional testing of the elevator's mechanical parts, electrical equipment, and safety protection devices, as well as measurement of the elevator's operating parameters. For example, the linkage test of the speed limiter and safety clamp can verify their reliability in emergency situations; the inspection of the elevator door anti-pinch device can ensure the safety of passengers when entering and exiting the elevator.

(III) Compliance points: full control from design to use

In order to ensure that residential elevators meet the requirements of GB 7588 and TSG T7007, strict control is required throughout the life cycle of the elevator. During the design phase, elevator manufacturers must strictly follow the standards of GB 7588, select parts and materials that meet the requirements, and ensure that the performance indicators of the elevator meet safety requirements. During the manufacturing process, quality control must be strengthened, and each production link must be strictly inspected to ensure that product quality meets the standards.

During the installation of the elevator, the installation unit must have the corresponding qualifications and strictly follow the installation specifications. After the installation is completed, apply for supervision and inspection in a timely manner and cooperate with the inspection agency to carry out various inspections. During the use of the elevator, the user unit must establish and improve the elevator safety management system, implement the daily maintenance of the elevator, and apply for regular inspections according to the prescribed cycle. At the same time, strengthen the training of elevator managers and operators, improve their safety awareness and operating skills, and ensure the safe operation of the elevator.

In addition, elevator industry regulatory departments should also strengthen supervision and inspection of the implementation of elevator safety standards and specifications, punish violations of regulations in accordance with the law, form an effective regulatory mechanism, and ensure the safe operation of residential elevators.

4. Maintenance strategy and fault prevention: the key to reducing long-term use costs

In the entire life cycle of residential passenger elevators, maintenance strategies and fault prevention are the core factors that affect their long-term use costs. As a special equipment used frequently, elevators gradually become more prone to problems such as component wear and performance degradation as the operating time increases. If there is a lack of scientific maintenance strategies and effective fault prevention measures, not only will the maintenance costs increase, but frequent faults may also cause the elevator to stop operating, causing inconvenience to residents and even causing safety accidents. Therefore, building a complete maintenance system and implementing forward-looking fault prevention measures have become the key to reducing the long-term use costs of residential passenger elevators and ensuring their safe and efficient operation.

(I) Intelligent

Maintenance: Opening a new model for elevator maintenance

Traditional elevator maintenance relies on manual regular inspections, which have problems such as low efficiency, strong subjectivity, and insufficient fault prediction capabilities. With the development of technologies such as the Internet of Things, big data, and artificial intelligence, intelligent maintenance has gradually become a mainstream trend. Intelligent maintenance collects elevator operation data in real time by installing various sensors on key elevator components, such as vibration sensors, temperature sensors, and current sensors, including speed, acceleration, vibration frequency, motor temperature, door opening and closing times, and other information.

These data are transmitted to the cloud server through the network and processed using big data analysis and artificial intelligence algorithms. For example, through long-term analysis of elevator vibration data, potential faults such as guide rail wear and bearing damage can be predicted; according to the change of motor current, it can be judged whether there is abnormal load in the traction system. Data from a smart maintenance platform shows that after adopting the intelligent monitoring system, the accuracy of elevator fault warning has increased to more than 85%, and the potential faults discovered and handled in advance have reduced maintenance costs by 30%.

In addition, intelligent maintenance also realizes the precision and visualization of maintenance work. Maintenance personnel can view the real-time operation status and historical data of the elevator through mobile APP or computer, and carry out targeted maintenance work according to the maintenance tasks and priorities prompted by the system, avoiding the blindness and repetitiveness of traditional maintenance. At the same time, property management personnel and regulatory departments can also grasp the maintenance status of elevators in real time through the platform, realizing multi-party collaborative management.

(II) Full life cycle management: controlling costs from the source

The long-term use cost of an elevator is not only related to the later maintenance, but also has a profound impact on the cost during the design, selection, installation and commissioning stages. We should promote the concept of elevator life cycle management, starting from the elevator planning and design stage, comprehensively consider factors such as building use requirements, elevator performance parameters, maintenance costs, and select cost-effective elevator products.

When designing and selecting, fully evaluate the compatibility of the elevator's load capacity, speed, parking accuracy and other parameters with the building. For example, for small and medium-sized residential projects, if an elevator with too large a load capacity and too high a speed is selected, it will not only increase the initial purchase cost, but also lead to an increase in operating energy consumption and maintenance costs. At the same time, pay attention to the energy-saving design of the elevator, such as using permanent magnet synchronous gearless traction machines, energy feedback devices, etc., to reduce the power consumption during elevator operation.

During the installation and commissioning phase, ensure that the installation unit strictly follows the specifications to ensure the quality of elevator installation. The installation quality directly affects the later operation stability and maintenance cost of the elevator. Irregular installation may cause frequent elevator failures, increase the number of maintenance times and costs. By strengthening the supervision of the installation process and doing a good job in acceptance, potential quality risks can be reduced from the source.

(III) Establish standardized maintenance processes and emergency plans

Standardized maintenance procedures are the basis for ensuring the quality of elevator maintenance. Develop detailed maintenance work instructions to clarify the maintenance content, cycle and standards of different types of elevators at different stages of use. For example, it is required to clean and lubricate the elevator door system every week, check the function of the safety protection device every month, and conduct a comprehensive inspection of the traction system every quarter. At the same time, establish a maintenance quality supervision mechanism to conduct regular inspections and assessments on maintenance work to ensure that maintenance work is implemented in place.

In addition, it is crucial to develop a comprehensive emergency plan for elevator failures. Develop detailed emergency response procedures and operating specifications for common failures and emergencies, such as elevator entrapment, power outages, and safety circuit interruptions. Regularly organize property management personnel, maintenance personnel, and residents to conduct emergency drills to improve the emergency response capabilities and coordination levels of all parties when facing elevator failures. Through rapid and effective emergency response, reduce the impact of elevator failures on residents' lives and reduce indirect costs caused by failures, such as residents' complaint handling costs and corporate reputation losses.

(IV) Cultivate a professional maintenance team and strengthen cooperation

A professional maintenance team is the key to the smooth development of elevator maintenance work. Elevator manufacturers, maintenance companies and property management units should strengthen the training of maintenance personnel to improve their professional skills and safety awareness. The training content should not only include elevator mechanical and electrical principles, fault diagnosis and repair technology, but also cover aspects such as intelligent maintenance system operation and emergency rescue knowledge. Through regular assessments and skill competitions, maintenance personnel are encouraged to continuously improve their business level.

At the same time, strengthen cooperation among all parties to form a good ecology of elevator maintenance. Elevator manufacturers should strengthen technical cooperation with maintenance companies, provide technical support and training services for maintenance work; maintenance companies should establish a close communication mechanism with property management units to provide timely feedback on elevator operation status and maintenance needs; government regulatory departments should strengthen supervision of the elevator maintenance market, standardize market order, and promote the healthy development of the maintenance industry. Multi-party collaboration will jointly ensure the safe operation of residential passenger elevators and reduce long-term use costs.