SOCIALIST REPUBLIC OF VIETNAM
VIETNAMESE STANDARD
CODE FOR SAFETY TECHNIC OF LIFTING APPLIANCES
TCVN 4244 – 86
HANOI
TCVN 4244 – 86 GROUP T
VIETNAMESE STANDARD
CODE FOR SAFETY TECHNIC OF LIFTING APPLIANCE /TCVN 4244 - 86
Be effective from 01 January 1987- General definition:
1.1The standard is to be applied to lifting appliances as follows:
a). Crane:
-Jib crane: Automobile crane, pneumatic-tyred crane, crawler crane, tower crane, base crane, rail crane, bracket crane, excavator, ………………….
-Bridge crane: Traveling bridge crane, portal crane, loading crane………………
-Cable crane
b). Rail-mounted winch truch
c). Power winch
d). Hand chain-block, hand winch
e). Building hoist
f). Loading parts
1.2.Lifting appliances as follows are to be exempted from the standard:
a). Shovels
b). Elevator using no cable or chain
c). Fork-lift truck
d). Lift
e). Floating lifting appliances
1.3.Load of a lifting appliance is the maximum allowable weight of the carrier for which will be calculated in accordance with a certain working condition.
The load includes the weight of grabbing bucket, electromagnet, cabin, body and other loading parts.
For reach-changeable crane, load will be defined according to the length of boom
- Technical requirements:
2.1. All lifting appliances and loading parts must be manufactured in compliance with the standard and approved designed as specified in Article 3.14
2.2. Power-drive lifting appliances must be ground-touched as per “ Temporary code for ground-touching of electric equipment QPVN 18 – 78”
2.3 Boiler of lifting appliances must be controlled and used in compliance with “ Code for safety technique of boiler, QPCV 2381”.
2.4 Compressed air vessels of lifting appliances should be controlled and used as per “ Code for safety technical of compressed air vessel, QPVN 2 – 75”
2.5. Registered lifting appliances (for those which need registration) can only be used after a permit is granted in compliance with the standard
2.6. For imported lifting appliances that do not meet the requirements of the standard, the owner of the appliances should make a declaration to the agency in charge of registration and license for settlement
2.7 For lifting appliance being used in inflammable and explosive conditions, safety measures for men and appliances should be mentioned in their designs. It is also specified in technical specification that the appliances are allowed to used in such conditions.
2.8. In the designs for lifting appliances operating in erosive environment (by acids, alkali…), appropriate measures should be defined
2.9. On calculating the durability of parts and components of lifting appliances, working conditions specified in Appendix No. 1 attached herewith should be put into consideration
2.10. Speed of lifting appliances operated from their Platform should not exceed 50m/min and of their trolleys should not exceed 32m/min.
2.11. Lifting appliances especially manufactured for assembly process or tasks of high precision, their moving and elevating mechanisms must be added with suitable speed.
2.12. For reach-changing crane, the possibility of change in the length of boom within loading limit should be mentioned.
2.13. Cranes with elevating and reach-changing mechanisms are subject to lower loads and booms by engines. Crane shovels and cranes using hydraulic clutches are excluded.
2.14.Possibility of automatic On and Off is subject to be excluded to Mechanisms of lifting equipments using positive – contact clutches, lever – actuated friction clutches and other mechanic bonds to start or change their speeds. Besides, winches are also excluded from mechanism – breaking – off when their brakes have not been applied.
It is permitted to use positive – contract clutch or lever – actuated friction clutch mechanisms to elevate people, melting metal, poison, explosive, explosive and use them in dynamic electricity – conducting mechanisms. Exception is made to cases follow:
a). Changing the speed of multi-speed moving or rotating mechanisms.
b). Controlling, in separate, each caterpillar of a crane using the same drive for its two caterpillars.
Brakes of the cranes stated in a. and b. above must have kinematics bonds with their rotating parts and caterpillars or wheels.
2.15.Parts of lifting appliance that helps drive torque moment must be bolted, keyed, and splined.
2.16. Central shafts holding drum, pulley sheaves, wheels, rollers and other rotators must be fixed to avoid any movement
2.17.Cranes with jib booms must have devices that help firmly locking the booms at any of their reaches.
2.18.Cranes’ bolts, keys and wedges must be protected from self-loosening.
2.19. Cranes’ pulleys and chain-dishes must be designed so as to avoid slings and chains jumping-off or stuck.
2.20. It is imperative to balance the pulley when using double tackles.
2.21. The pulley of a manual drive-lifting appliance must be fixed on shaft to avoid sling jumping-off. The sling must meet the length in such a way that one of its ends is 0.5m from the floor where the operator stands.
2.22. A shock absorber is essential for the elevating mechanism of the crane serving forging.
2.23. Steel structures and parts of lifting equipments must be protected from rust.
Furthermore, proper measures to avoid rain and water stagnation on box or pipe structures when the lifting appliance works out-door.
2.24. Safety accesses to safety or electric equipments, steel structures, booms, pulleys etc., which need to be regularly checked and maintained, are needed. Whatever no accesses to must be ensured probability for lowering
2.25. Truck, lorry – mounted, caterpillar, rail, tower, base, trailer and shovel cranes should always be kept in good condition (either or neither working).
Article 2.26 of the standard is the base for calculating and checking the stability of the cranes (when loading or unloading).
2.26. The stability of cranes is stipulated as follows:
Putting forward as a hypothesis for load and unload safety:
-The bevel angles of base cranes must not lower than 10.
-The bevel angles of other cranes, except rail crane, must not lower than 30.
The declination of rail, at curving parts, of non-base cranes must be taken in to
account. Accordingly rail clamps is not considered.
Adjunctive supporters and other reinforcements are not included when calculating the safety of cranes.
The weight of the lower part of the chain and other parts that do not help keep the booms from falling is excluded when calculating safety.
In the case that steam boilers, water and fuel tanks are attached to parts affecting the stability of the crane, water level must be highest and fuel limited when calculating the safety of the crane.
In the assembly and using manual of a crane, there must be clearly stated the direction of the boon against the non-slewing parts of the crane and whenever the adjunctive support is need.
The coefficient of load safety is the ratio between the moment of weight of crane’s parts with additional forces (wind pressure, inertia when starting and stopping elevating, slewing and moving mechanisms) and the effect of the most allowable bevel angle to upturned side and moment to upturned side. The coefficient of load stability is not lower than 1.15.
The value of the coefficient of load stability is, considering the torque inertia created when braking pivoting mechanism, calculated when the boom direction quadratures upturned side and when the boom direction and upturned side create an angle of 450. The value is calculated on the base of the formula shown in appendix 2.
The value of the coefficient of load safety is, not considering additional forces and the effect of ground declination where the crane is located, not lower than 1.4.
The unload stability is, considering the ground declination toward the upturned side and the moment of wind force toward the same upturned side, defined by the ratio between the moment of the weight of crane’s parts.
The unload stability is, under formula shown in appendix 2, defined when the crane is in its most unfavorable condition to the wind force. To a crane which changes its reach by boom elevating and lowering mechanism, the coefficient of unload stability is defined when the boom is in its lowest working position (the unload stability, in the case, is also checked when the boom is in its highest working position bearing wind force), and a crane which does not use the mechanism to change its reach, the coefficient is defined when its boom is in its lowest reach bearing wind force.
2.27. The rail pitch of the trolley of a moving, non-moving or bracket crane does not exceed 0.0003 when the cart is in its highest load and most unfavorable position.
The pitch standard is applied to crane’s trolley armed with automatic brake or moving by cable.
2.28 Improvement to a lifting appliance (changing the drive, hook for bucket, electro magnet, increasing aperture, boom’s length, lifting elevation, or reinforcing to increase the capacity) and other changes, which increase or redistribute force to parts and components or decrease the load or unload safety must be implemented according to approved design as regulated in the standard.
The actual condition of the lifting appliance must be taken into account when designing the improvement (corrosion, decay.).
When shortening boom or tower in which manual the manufacturer requires possibly no design with very detailed calculation, measure to ensure quality is also necessary.
Change from an excavator, a pipe-layer etc., into a crane is subject not to implement without detail design approved by the Committee of Safety Technique and Labor Protection Inspection under Department of Labor.
2.29.Lifting appliance Management Agencies are to, in finding mistakes in structure, manufacture and anything that does not meet the standard when assembling, doing technical test or using, make a complaint to the manufactures. The complaint will be through the importer if it is an imported appliance.
Duplicates of the complain letter have to be sent to the agency which licensed its manufacturer and to the Committee of Safety Technique and Labor Protection Inspection under the Ministry of Labor.
The manufacturer has to improve the found mistakes brought forward in the letter, count up all the complaints in a record book that contains items as follows:
a). Name of complainer.
b). Brief of the complaints.
c). Production Number
d). Settlement
2.30.2.30 The manufacturer has to take into account mistakes in the structures and manufacturing of using lifting appliances and find ways for improvement. If the found errors may effect the safety of the lifting appliance, they have to notify all those whose are using such a kind of appliance and carry out necessary improvement, and at the same time sent documents concerning technical specification, materials and parts and components for replacement
A duplicate of the information on errors and method of improvement sent to users must be sent to the State Agency of Safety Technique Inspection.
- Manufacturing and repairing permit.
3.1.Manufacturers of lifting appliances and load carriers must be licensed by the State Agency of Safety Technique Inspection, as stipulated in the standard
3.2.Manufacturing permit is only given to those organizations, which are capable of technique, welding and checking the quality of welding joints.
3.3.Manufacturing permit for cranes with the capacity of 1 ton and above and series of other lifting appliances is given by the State Agency of Safety Technique Inspection.
The application for manufacturing license comprises:
a). Application for manufacturing license
b). Decision from ministry (or organization of the same rank) or department assigning the organization to manufacture lifting appliances for them.
c). Approved common drawing of lifting appliances and their main parts and components.
d). Approved technical specifications
e). Proof of welders of grade 4 and above.
f). Biography of the organization.
g). Assembly and using manual
h). Letter of checking before acceptance of sample (for mass production).
3.4.Manufacturing license for kinds of lifting appliances which are not brought forward in article 3.3 above is given by local Agency of Safety Technique Inspection.
Application for the permit comprise:
a). Application for manufacturing license
b). Common drawing of lifting appliances and their basic parts and components
c). Approved technical specifications
d). Proof of welders of grade 4 and above.
3.5Manufacturing permit for master parts and components (steel structures, load carriers and brakes) and a variety of other parts of the lifting appliances is given by the local Agency of Safety Technique Inspection.
Application for the permit comprises:
a). Application for manufacturing license for parts and components (names listed)
b). Common drawing of parts and detail drawing.
c). Approved technical specification
d). Proof of welders of grade 4 and above, if welding is needed
e). Letter of checking before acceptance of the sample.
3.6 The stipulation of technical specifications for manufacturing lifting appliances or steel structures, besides others, also includes:
-Requirement of controlling the qualification of welding joints and rejection
-Material for manufacturing and welding
-Procedure of checking before acceptance of semi-finished and finished products.
3.7In the manual for assembling and operating lifting appliances, besides others, it is essential to have instruction in checking and lubricating periodicity, method and periodicity for adjusting brakes, checking steel structures; allowable wear of important parts; possible failure of steel structures and improvement; periodicity for checking the appliances stated in the stipulation of Safety Maintenance and Operation of lifting appliances. There must be stipulated safety using-conditions for the appliances using buckets or electro magnet as their load carriers.
Measures to ensure the quality of welding and method for checking welding-joints are to state in the manual if welding is needed when assembling lifting appliances.
3.8.Testing and taking over the trial manufacture of a lifting appliance is taken to find if the sample meet the standard and design, its quality and structure meet technical specifications and safety operation respectively.
The test must be taken according to procedure made by the designer.
In testing its safety, the crane have to elevate a weight which is 1.4 times heavier than its load when its boom is in its minimum safety position.
The crane is considered accepted when it can lift a weight 40% heavier than its load to the height of 100 – 200 mm and hold suspended for ten minutes; it is not considered unsafe if one of the boom’s fulcrums is tilted.
Besides, lifting appliances must, with all operations, be tested when carrying a weight 125% heavier than its load. The result will have to be in written.
It is not necessary to retake test and taking-over to lifting appliances manufactured before the promulgation of the standard. Manufacturers, to be re-licensed, only need to present a duplicate of the available report.
The test and taking-over of trial-manufactured lifting appliance must be participated by representative from the State agency of Technical safety Inspection.
3.9.Each and every lifting appliance manufactured must be through the quality control department of the manufacturer.
In releasing from the factory, a lifting appliance must be attached by its original file, which comprises:
-History(record book) of the appliance
-Safety assembly and operation manual.
3.10.Each manufacturer has to have a record book, which counts up the lifting appliances displayed for sale. Each ex-work appliance must wear a metal place on which written name of manufacturer, load, ex-work date and number.
3.11. License for repairing and reconditioning the steel structures of lifting appliances (with welding) is issued by local agency of safety technical inspection. Application for the license comprises:
a). Application for license for repairing and reconditioning steel structures of lifting appliances.
b). Proof of welders of grade 4 and above
3.12.Those who repair and recondition steel structures of lifting appliances have to establish technical specifications, define materials for manufacturing and welding, method for controlling welding-joints, criteria for rejection, procedure for taking over and making papers.
3.13.Those who repaired and reconditioned the steel structures of lifting appliances must write in their attached papers (history) the work they have done and the material they have used.
In some cases, new papers (history) will be made for repaired or reconditioned lifting appliances.
3.14.Designs for lifting appliances, their parts and components (including designs for repairing and reconditioning) must be approved, basing on the stipulations in the standard, by the head of the designing agency.
3.15. Designs for lifting appliances must include such requirements:
a). Meeting the stipulations in the standard and other related codes and standard.
b). Having all safety equipments.
3.16.Issuer may withdraw license for manufacturing from those who display for sale unsafe lifting appliances.
- Materials, welding and controlling the quality of welding-joints
41. Materials for manufacturing and repairing the steel structures of lifting appliances and parts of elevating mechanisms must be durable, pliable, safe and facile for welding as defined.
At present, Soviet Union’s standards are applied to materials.
4.2 Quality, properties of materials and semi-finished products must be controlled by manufacturers in written text
Whenever there is no written text mentioned-above, a test has to be taken by its manufacturer, assembler or repairer of the lifting appliance. The appliance will not come in to use if the result does not meet the defined technical specifications.
4.3Material suppliers have to hand over all documents of technical specifications to buyers. In case there is not enough original document made by the manufactures, they must provide the duplicates.
4.4Welding the force bearers of lifting appliances must be done according to procedures for welding technology.
4.5Materials for welding the steel structures of lifting appliances must ensure ultimate strength, yield limit, relative-stretching length, curving angle, notch strength, not lower than inferior limit of the properties of basic metals. The requirements are applied to welding hand-rails, suspending ladders.
When welding metal with different marks, the priorities of welding metal must similar to that of metal with superior ultimate strength.