【 Weak current College 】 Dooly overspeed protection device inspection problems

Dooly overspeed protection device is installed in the traction lifts on important security components, transmission failure occurs when the elevator and brake failure, fault resulting in uplink speed to a certain extent the action for the protection of passengers in the car and property security. It is GB7588-2003 new increase of one of the important content. National standard mandatory elevator GB7588-2003 has been in operation for a year, in the elevator inspection have not been revised statute, not on uplink overspeed protection device for inspection before making uniform provisions, inspection method around. The authors combine on GB7588-2003 learning and testing work on traction elevators uplink overspeed protection device for inspection methods and laboratory findings. Errors and anomalies, please humour.

1. the uplink overspeed protection device for common type

GB7588-2003 9.10 on Dooly overspeed protection device for composition, operation speed, stop deceleration, verify that the contact points and action mode and so clearly. Uplink overspeed protection device and downlink overspeed protection device, including speed monitor parts and components. Its speed monitoring part by GB7588-2003 requirements should be and downlink overspeed protection device like a builder, or meet the speed limiter characteristics requirements, actions, demands, and choose the required speed monitoring device. Currently, most manufacturers have adopted the Governor as an uplink speed of the overspeed protection device monitoring components.

The deceleration components according to their site of action is different there are four different types. (1) to the car's deceleration components are usually takes up safety clamp (hereinafter referred to as cabin safety clamp class). Currently, the manufacturer has introduced two-way safety clamp, uplink security clamp is a separate device in the upper part of the cabin. (2) on the weight of gear components generally is to clamp down on security (hereinafter referred to as the security clamp class). Secure clamp as deceleration components, and speed monitoring part of the drive way and downlink overspeed protection device of the same by rope and lever mechanism of mechanical drive. GB7588-2003 the article must not be used 9.8.3.2 electrical, hydraulic or pneumatic control devices to manipulate security clamp. (3) on a rope system of deceleration components mainly clip cord unit (hereinafter referred to as wire rope clip cord converter class), the device can be set in the room of host shelf or wells road, within the structure, you can apply a hanging rope or rope to compensation. Wire rope clip cord converter braking force generated by the main components with hydraulic system, compression springs, compact disc spring and wedge self-locking, etc. Currently, manufacturers use the most common is installed in the engine room host shelf for suspension rope to spring mechanism as clamp cord power source of the rope. According to pinch the rope for trigger, wire rope clip cord converter class uplink overspeed protection device is divided into speed limiter Gates line pull and electromagnet power triggered two types. Clip cord clamping device types after reset or many, the most common is the screw rotation reduction, clamping device reset should unscrew the screw to the appropriate location. (4) acts on the traction wheel or closest traction axle reduction gear units, on which a direct role in traction wheel or closest traction axle of a braking device (hereinafter referred to as brake class), are now mainly refers to the gearless traction machine, planetary gear tractor or belt drive traction. If machine? brakes are direct braking traction wheel or traction wheel one brake wheel (wheel), and the brake and fully meet the requirements of the 2003 GB7588-safety brake, then this machine? brakes can concurrently uplink overspeed protection device for deceleration components in monitoring part checkout Dooly speeding when the action so that the car system to stop or slow down.

On uplink overspeed protection device actions of validation, the standards require the entire upstream overspeed protection device has an electric safety devices in the uplink overspeed protection device actions after cutting off the driver host, and brake power, and to prevent the lift starts. Currently, the majority of manufacturers in the uplink speed of the overspeed protection device monitor parts and deceleration components are set up electrical safety devices that make up overspeed protection device more secure and reliable.

2. elevator inspection in uplink overspeed protection device for testing

2.1 information review

Inspection, first check the manufacturer's type test report on uplink overspeed protection device forms, model and factory certificate compatibility on the model. If there is a upstream overspeed protection device for installation instructions, a new stair acceptance testing should also verify the factory certification on uplink overspeed protection device models and entire ladder-type test report configuration is consistent.

2.2 site inspection

2.2.1 appearance inspection

Field should check up the speed of the overspeed protection device monitor parts and deceleration components of the model, serial number and factory certification number on the model, are the same. Also check speed monitor parts and deceleration components look normal, there are no obvious deficiencies. The installation was correct and reliable.

2.2.2 operation test

Uplink overspeed protection device action test usually can be adopted and the elevator down security clamp similar test methods, that is, in the cabin layout and the corresponding load evenly to overhaul speed uplink, human action uplink speed of the overspeed protection device, check the deceleration control parts whether components, car is a reliable system. The author in the actual testing of multiple "dynamic test method" method. We all know, traction lifts site inspection to achieve downlink speed elusive, but the car wheels, due to weight ratio of car weight, to achieve when speeding it up easier. Thus, the upward movement of the overspeed protection device test fully enables Dooly actual speeding to a dynamic test. "Dynamic test" test, the car in the lowest layer station no-load, disconnect the total power, an elevator used to release the brakes pine brake wrench for car to car rolling on, another person to Dray or Governor rope using speed detector monitoring car speed, when the uplink speed of the overspeed protection device monitoring unit (Governor) of uplink speed switching action, make a note of theMovement speed, check whether the speed of movement speed range (see Figure 1). And watch the deceleration components is action, the cabin can slow down and stop.

"Dynamic test" attention: (1) shall arrange special observation car, if car slipped to near the top station and deceleration components yet action, manipulate those loose brake wrench should immediately release the wrench, let the brake to avoid car-top accidents. (2) when the action is when deceleration components loose brake wrench is still leading the brake to completely rely on the deceleration components will slow down and made the car stops to verify their reliability. (3) actual inspection found that when the elevator station less than 6 layer (that is, when well road height is low), this method is difficult to make the car reaches the overspeed protection device upstream movement speed. At this point you can take the empty car from the ground up and running, a manipulation loose brake wrench for brake has been leading, suddenly loses power, gave the car a muzzle velocity of its acceleration to speed up action. If you still can not reach the ascending movement speed, you can only take usually similar safety clamp test of speed test for simulation speed. (4) this Act does not apply to the "brake class" uplink overspeed protection device for inspection.

"Dynamic test" as the simulation of uplink overspeed protection device for practical action condition, its advantages are established inspection uplink overspeed protection device movement speed is qualified, and detect the uplink overspeed protection device in speeding the validity and reliability when. At the same time can also detect clip cord converter class uplink overspeed protection device by electromagnet triggered in a power outage, the reliability of the electromagnet. But testing is important to note that security.

3. uplink overspeed protection device for practical problems found during inspection

3.1 recognizes common misconception

For uplink overspeed protection device in the country is only introduced a new concept of Elevator Safety parts, elevator manufacturer, installation, inspection agencies and user awareness has not yet been fully consolidated, many people think that uplink overspeed protection device is superfluous, mainly in the old staircase renovation without installing uplink overspeed protection device, a new stair installation uplink overspeed protection device or after acceptance inspection will clip the rope for reduction screw tightening pressure die clamping device of the clip the rope rope cannot action loses the function. Some people believe that uplink overspeed protection device test especially dynamic test would damage rope and elevator and the test did not understand.

3.2 device itself problems

Because the domestic uplink overspeed protection device for manufacturing is still in its infancy, diverse, great variety, it should be said that part of the uplink speed protect equipment reliability is not high, the examination has a malfunction occurs, most sophisticated effort reduction of special reset tool but does not have. There are of pinch the rope for action after reset Reset sheet visible distortion.

3.3 problems during the installation

Uplink overspeed protection device are completely new security components, most manufacturers have not equipped with detailed installation and commissioning manual installer without specialized training, inspection and found the uplink overspeed protection device installation problems, no less, of the speed limiter direction anti-loaded; some clip cord converter class uplink overspeed protection device in the brake lines not properly when debugging the tightness will rope head pull off; there's too much of the brake lines or brake lines consistent curvature RADIUS is too small, when Governor action clips rope device without action.

GB7588-2003 increase uplink overspeed protection device in order to ensure the elevator more secure, if manufacturers uplink overspeed protection device reliability is not high, it is not convenient to use; installation units installed incorrectly; inspection bodies not strictly. The result would be counterproductive. Hence the urgent need for countries as soon as possible the uplink overspeed protection device for uniform inspection method so that the correct test and inspection bodies strictly, so that the uplink overspeed protection device is more reliable, more secure elevator.