[Hydraulic Tools] Research on the Improvement of Standards of Fire Hydraulic Breakage Tools

Abstract : A comparative study on the standard of hydraulic tools for dismantling at home and abroad was carried out. The classification and basic parameters of hydraulic tools, anti-eccentric performance, anti-slip performance, safety, and standardization of hydraulic joints were studied. Development of a standardized test device of hydraulic rescue tools, including work platform, hydraulic and electrical control cabinet, computer console three parts, to carry out comprehensive performance testing of hydraulic rescue tools to provide technical support for the revision of the standard hydraulic rescue tools.

Keywords: fire protection; hydraulic rescue tools; anti-eccentric performance; anti-slip performance

The public security fire brigade will use various types of fire emergency rescue equipment when handling traffic accidents, building collapses and other disasters. Among them, hydraulic rescue tools are used as main battle equipment, which can be used for rescue operations such as expansion, shearing, top support, traction, and extrusion, and can directly remove obstacles from buried or trapped persons. Their performance and efficiency often directly determine the rescue effect. .

The hydraulic breaking tool consists of a breaking tool, a power source, and an attachment. The breaking tool includes a dilator, a cutter, a scrambler, and a top support, and the power source includes a motorized pump and a hand pump. At present, the national fire-fighting force is equipped with more than 20,000 hydraulic rescue tools , and it is growing rapidly at a rate of 4 000 newly installed each year . In order to ensure the quality of hydraulic rescue tool products, China adopts GB / T 17906 - 1999 { General Technical Conditions for Hydraulic Breaking Tools ( hereinafter referred to as "Rescue Tools Standards" ) for product testing . The standard has comprehensively evaluated the comprehensive performance of the hydraulic rescue tools at the time of establishment and satisfies the needs of the firefighting force. Therefore, it is still in use today. With the continuous emergence of new technologies, materials, and processes for hydraulic tools, and the concept of “people-oriented” gradually gaining popularity, the original standards for fire hydraulic tools have been difficult to meet the requirements. The following major problems exist: The original standards are only Applicable to medium-sized products, lack of serialization requirements, resulting in large products with strong demolition capabilities and portable products can not enter the fire-fighting force; the use of product safety requirements less, the use of the product there is a certain risk The lack of unified products, products from different manufacturers can not be matched, resulting in a lack of linkage between the firefighting forces. Therefore, it is imperative to carry out research on the improvement of the standardization technology of the hydraulic rescue tools, and lay the technical foundation for the revision of the "Rescue Tools Standard".

1 Comparative Study abroad hydraulic rescue tools standard

The most representative hydraulic breakage tools in the world are German standards and American standards. German Standardization Committee from the beginning of 2O century 8O's, has issued the DIN 14751 "Hydraulic rescue equipment Fire" series.

In 2004 , the 1st , 2nd and 3rd parts of the series of standards were merged and approved by the European Committee for Standardization (CEN) to form the European standard DINEN 13204 - 2005 - Firefighting and Lifesaving Double Action Hydraulic Lifesaving Tools ( below Referred to as "European Rescue Tool Standard" ) . The US National Standardization Committee began to formulate NFPA 1936 “Power Rescue Tool Standards” in 1999. After two revisions, the current standard uses the 2010 version. The standard involves power sources that include not only hydraulic pressure but also electric and pneumatic power. .

At present, the hydraulic rescue tools imported by our country's fire-fighting forces are mainly produced in Europe. Therefore, we compare Chinese standards with European standards, as shown in Table 1 .

Table 1 Comparison of Hydraulic Breakout Tool Standards between China and Europe

As can be seen from Table 1 , the same parts include: terms and definitions, basic performance parameters, technical requirements for the demolition tools ( high and low temperature, seal, self-locking, controlled directional valve, reliability, etc. ) , power source technical requirements ( (High and low temperature, safety valve, reliability, full-load working time and other performance ) , different parts of the test method include: type, technical requirements of the rescue equipment ( quality, strength, anti-eccentricity, anti-slip, safety, vibration, bending of the piston Stability and other performance ) , power source technical requirements ( quality, action, anti-flip start, anti-slip performance , etc. ) , accessories technical requirements ( hydraulic hoses, joints ) .

2 Research on Standardization Technology of Hydraulic Breakdown Tools

2 . 1 Classification and standardization of basic parameters

In view of the level of hydraulic technology in China at that time, hydraulic break tools in our country were only divided into 31 according to the rated working pressure . 5 , 63 . 0 MPa two types. From the current domestic and foreign hydraulic rescue tools products, there are 31 . 5 , 35 . 0 , 37 . 5 , 63 . 0 , 70 . 0 , 75 . 0 MPa and other rated working pressures, and the technology is mature. Therefore, it is recommended that when the standard is revised, the Hydraulic Breaker tool is set to a nominal working pressure of 31% . 5 , 63 . 0 MPa limit.

At the time of classification, the municipality referred to the “European Rescue Tool Standards”. According to the work ability, the hydraulic rescue tools were divided into three categories : light, medium, and heavy , and combined with the requirements of the actual professionalization of the fire-fighting force in China to determine various types of hydraulic breakage. Dismantle tool performance parameters, as shown in Table 2 .

Table 2 Classification and Basic Parameters of Hydraulic Breakdown Tools

2 . 2 Standardization study on anti-eccentricity performance and anti-slip performance

During the use of the hydraulic rescue tool, due to the restriction of the rescue environment, it is often impossible to ensure that the tool is always placed in the best direction of force and work position. Reference can be made to the "European Rescue Tool Standards" to increase the anti-eccentricity and anti-slip performance requirements of the hydraulic rescue tools in order to improve the rescue capabilities of the hydraulic rescue tools in harsh environments. The test test method for anti-eccentric performance and anti-slip performance is:

The test test method for anti-slip performance is:

(1) Anti eccentric force test, the dilator, expandable cutting despreader 50 to the maximum expansion distance, the maximum expansion force is applied in a width expansion arm to the top of 5O. 25 times the eccentric force, sustained 60 s , there should be continuous leakage, visible permanent deformation, fracture or mechanical damage, as shown in Figure l .

Figure l Anti-eccentricity performance test of expander and shearer

(2) During the anti-slip test, the tip of the expander arm of the expander and the shear expander is inserted into the test device, the length of the extension is 25 mm ; the supporter is extended to the length of the support top 95 , and then pressurized to the rated working pressure For 60s , there should be no slipping pop-up phenomenon, as shown in Figure 2 .

Fig. 2 Test of anti-slip performance of expander and shearer

2 . 3 Security Standardization Study

In order to improve the safety of the use of hydraulic rescue tools, the existing standards can be revised as follows.

(1) Hydraulic breaking tool strength test pressure from the rated working pressure of 1 . 3 times increased to 1 . 5 times to avoid the danger of hydraulic system failure.

(2) The design of the upper handle of the rescue tool shall prevent the operator from touching any parts ( such as arms, blades or clamps ) that are in operation when the fingers are open , and the distance exceeds 180 miD . To avoid the fingers involved in moving parts, as shown in Figure 3 .

Figure 3 Safety Distance Requirements

(3) The technical requirements for hydraulic hoses have been increased to prevent twisting, tension, leakage, etc., improving the reliability and ease of use.

2 . 4 Standardization and Unification of Hydraulic Joints

Hydraulic fittings are standard accessories for hydraulic rescue tools. However, whether domestic or foreign standard criteria, have no hydraulic rescue tool systems ⋯ provisions with the structure and size of the quick coupling, resulting in quick connectors of different enterprises at home and abroad production of hydraulic rescue tools used are not the same, each No enterprise can match the rescue tools. Therefore, firefighting forces can only purchase complete sets of hydraulic rescue tools, and they can only be scrapped when they scrap the hydraulic rescue tools, resulting in a huge waste of procurement funds, which seriously weakens the fire fighting forces' ability to co-operate and adapt to complex environments. Ability.

Through the standardization and unification of hydraulic quick-release tool quick joints, the structural types and dimensional parameters of the new joints are written into the standard.

(1) The quick interface used by the hydraulic rescue tool should have a locking function and a dust-proof device.

(2) In the unconnected state, the quick interface is at the rated working pressure. For 60 s , there should be no leakage.

(3) In the connected state, an axial tension of 1 000 N is applied to the quick interface to maintain 60 s . After unloading, it is pressurized to the rated working pressure and maintained for 60 seconds . It should be free from damage, leakage or permanent deformation.

3 Research on Standardized Test Equipment for Hydraulic Breakage Tools

In order to carry out the comprehensive performance test of the hydraulic rescue tools, a standardized test device for the hydraulic rescue tools was developed. The system is divided into three parts : working platform, hydraulic and electrical control cabinets, computer consoles , as shown in Figure 4 . The device adopts a combination of pneumatic and hydraulic pressurization and a dual power source compound hydraulic system structure. The maximum working pressure reaches 150 MPa and fully meets the needs of strength test. It adopts a hierarchical control strategy based on PID flexible control technology to achieve the work force in the new standard. The intelligent control of work stroke, strength, sealability, reliability, self-locking performance, manual Control Valve performance, etc., and the first time in China to achieve anti-eccentric performance and anti-slip performance test. After testing, the measurement accuracy of the device meets the detection requirements.

4 hydraulic rescue tool performance test

In order to verify the results of the research, five kinds of typical hydraulic rescue tools at home and abroad were selected. Tests were carried out on standardized test equipment for hydraulic rescue tools. The results are shown in Tables 3 and 4 .

Table 3 Dilator Verification Test Results

Table 4 Proofer verification test results

The standardization of the basic parameters, anti-eccentricity properties and anti-slip properties of hydraulic hydraulic tools is feasible and accurate.

5 Conclusions

Developed safety, graded, anti-eccentric and anti-slip properties of hydraulic rescue tools, developed a new type of hydraulic rescue tool full-performance test equipment, carried out research on key technologies for the standardization of quick joints, and revised hydraulic demolition for China. The tool standard lays the technical foundation, promotes the technical progress of the fire rescue equipment industry, improves the overall quality of fire rescue equipment products, and purchases high-performance, high-quality, safe and reliable equipment for the fire-fighting forces, and improves fire protection. The efficiency of the demolition operations in the fire fighting and rescue operations of troops is of great significance.

This article comes from "fire equipment research."