State Administration of Quality Supervision: Notice on the Opinions on the Renovation of Metallurgical Lifting Machinery

Bureau of Quality and Technical Supervision of Provinces, autonomous regions and Municipalities directly under the Central Government :

On April 18, 2007, a steel ladle capsized in Qinghe Special Steel Co., LTD., Tieling City, Liaoning Province, resulting in the death of 32 workers at the site. In accordance with the requirements of the Notice on Carrying out Hidden Danger Investigation of Special Equipment and Special Rectification Action of Lifting Machinery issued by the State Administration of Quality Supervision (AQSIQ Special Letter (2007) No. 355), all localities have carried out work deployment. According to preliminary understanding, only Liaoning, Jiangsu two provinces found for the metallurgical industry of non-metallurgical lifting machinery more than 2000 sets. In order to ensure the use of this kind of equipment safety, combined with the production and management of enterprises, after research, the metallurgical lifting machinery renovation work notice is as follows:

A, in use of non-metallurgical lifting machinery for lifting molten metal remediation requirements

(1) For those who have used the general bridge crane to lift the molten metal, the casting crane shall be replaced with the casting crane that meets the requirements of JB/ T7688.15-1999 "Casting Crane Technical Conditions for Metallurgical Cranes". If the unit does not have the conditions to replace the casting crane due to plant, foundation and other factors, in addition to meeting the general bridge crane regulations and standards, the original crane must be transformed and meet the following basic technical requirements:

1. Metallurgical crane special motor, when the ambient temperature exceeds 40℃ occasions, should choose H class insulation motor;

2. Equipped with two sets of independent brake (double brake);

3. Weight limiter must be installed;

4. Installed with different forms (generally used with heavy hammer and rotary) of the lifting limit position of the double limit (double limit), and should control different circuit breaker, lifting height of more than 20m crane, should also be installed according to the need to drop limit position limit;

5. With thyristor stator voltage regulation, eddy current brake, energy consumption brake, thyristor power supply, DC power supply speed regulation and other due to speed regulation may cause speeding lifting mechanism and 20t above used for lifting molten metal general bridge crane must have overspeed protection;

6. The lifting mechanism should have the fault protection function of positive and negative contactor to prevent the motor from losing power while the brake is still energized, resulting in stall;

7. The protection level of all electrical equipment shall meet the provisions of relevant standards;

8. Protective measures shall be taken for the electric control equipment of hoisting machinery working in high temperature environment for a long time;

9. Select wire rope suitable for high temperature occasions, and has sufficient safety factor;

10. Cast iron pulleys shall not be used;

11. The original crane working level is lower than A6(not including A6), should reduce the load use, the decrease range should be based on the actual working situation, but the load reduction after the provisions of the lifting weight shall not exceed 80% of the original rated lifting weight.

(two) For all kinds of lifting machinery that have adopted rated lifting weight greater than 10t with electric hoist as lifting mechanism, it is not allowed to lift molten metal.

(three) For the use of rated lifting weight less than or equal to 10t with electric hoist as lifting mechanism of all kinds of hoisting machinery to lift molten metal, must be replaced or rebuilt on the original crane and meet the following basic technical requirements:

1. Shall not use ordinary electric hoist as lifting mechanism;

2. With support brake and safety brake;

3. With different forms of lifting double limit (lifting height of the crane is greater than 20m, should also be equipped with falling limit position limit);

4. With lifting weight limiter;

5. Electric hoist with high temperature heat insulation protection function;

6. With sufficient safety factor in the condition of lifting molten metal, the working level should reach M5 (including M5) or above;

7. Select wire rope suitable for high temperature occasions, and has sufficient safety factor;

8. As far as possible, remote control and other manipulations away from heat sources must be adopted; otherwise, a safe passage must be set for operators.

(4) the transformation of the above crane must be carried out by the unit with the transformation license qualification, the transformation must be informed of the procedures, the transformation of the crane, must pass the qualified inspection and testing institutions in accordance with the "lifting machinery supervision and inspection Rules" and the requirements of this article for supervision and inspection, qualified, can be put into use in accordance with the provisions.

(5) The transformation work of lifting the molten metal crane shall be completed before June 30, 2008. The user shall immediately formulate a replacement plan or transformation plan and promptly implement it. Otherwise, the user shall stop using it. During the transformation period, the user unit shall monitor the use and must take effective measures to ensure the safe operation of the equipment.

(VI) The periodic inspection cycle of the crane transporting molten metal is shortened from 2 years to 1 year.

Two, the new factory installation of lifting molten metal crane requirements

Cranes newly installed at the factory for lifting molten metal refer to lifting machines for lifting molten metal that have been installed at the factory since the date of publication of this article, excluding lifting machines for lifting molten metal that have been overhauled, reformed or removed.

(a) The requirements of the crane for the installation of molten metal are as follows:

1 rated lifting weight greater than or equal to 75t crane, must be selected in line with JB/T7688.15 -- 1999 "metallurgical crane technical conditions casting crane" requirements of the casting crane.

2. For cranes with rated lifting weight less than 75t, general bridge cranes with working level A7(including A7) or above should be selected, but their configuration and other requirements must meet the 11 basic technical conditions and corresponding requirements of the reconstructed cranes in Article 1 (1) above.

3. The crane with electric hoist as lifting mechanism to lift molten metal can only be used for rated lifting weight less than or equal to 10t working conditions, its configuration requirements, must meet the basic technical conditions and corresponding requirements after the transformation of the first (3), The working level of the electric hoist requirements from M5 level (including M5 level) above to M6 level (including M6 level) above.

(2) Cranes transporting melting non-metallic materials (temperature lower than molten metal) and transporting hot solid metal can be relaxed according to the degree of danger in the workplace, or can be treated with reference to the above requirements.

Local bureaus of quality and technical supervision shall take effective measures as soon as possible to do a good job in the remediation of non-metallurgical cranes used in the metallurgical industry and prevent the recurrence of similar accidents. Please report any problems existing in the work to the Special Equipment Safety Supervision Bureau of the State Administration of China in time.