GB/T 43909-2024Forklift truck attachments - Safety requirements (English PDF)

3 Terms and definitions

One term is defined. A forklift truck attachment (3.1) is a relatively independent working device added to the forks, the fork carriage or the mast of a forklift truck, by hanging or by some other form of fitting, in order to extend the working functions of the truck.

4 General requirements

4.1 The moving parts of the attachment shall move freely, without sticking and without abnormal noise. 4.2 The attachment shall be designed so that the operator has a good field of view and can carry out the various operations. 4.3 The permissible deviation of the mass of the attachment is +/-3 % of the design value. 4.4 The mounting class and the dimensions of the hook shall meet GB/T 5184.

4.5 Measures shall be taken to prevent the attachment from moving unintentionally or falling off the truck unintentionally, and the movements of the attachment and its accessories shall have a mechanical end stop at their terminal positions. 4.6 After a dynamic load test at 1.1 times the rated lifting load, the hydraulic system shall show no oil leakage.

4.7 Parts that present a crushing or shearing hazard to an operator in the normal operating position, other than the load bearing parts, shall be adequately guarded; where a hazard remains, it shall be made known in the instruction handbook as required by Clause 10 and a warning sign shall be applied to the attachment as required by 11.2.

5 Metal structure

5.1 In designing the metal structure, measures shall be taken so that the structural parts meet the requirements for strength, including fatigue strength, stability, rigidity and other aspects of safety during use. The structure shall have enough strength to show no permanent deformation and no damage after a static load test at 1.33 times the rated load, and shall be laid out so that inspection and maintenance are easy.

5.2 The material of the load bearing structural parts is chosen with regard to the importance of the structure, the load characteristics, the stress state, the connection method and the working ambient temperature. The material of the main load bearing structural parts shall have mechanical properties not lower than those of Q235 steel of GB/T 700. Cast steel parts should use cast steel meeting GB/T 11352 or GB/T 14408, and spheroidal graphite iron parts should use iron meeting GB/T 1348; those three standards appear only in the Bibliography of the document, not among its normative references.

5.3 The type and the dimensions of the welded joints of structural parts shall meet GB/T 985.1 and GB/T 985.2, and the welds shall show no cracks, undercut or weld beads; stress relief after welding shall be carried out where necessary. Steel welds of the attachment are graded B, C and D according to GB/T 19418: class B welds shall be inspected 100 %, class C and class D welds may be inspected on a sampling basis according to the circumstances, and butt welds shall undergo surface flaw detection whose acceptance level shall meet Table 1. Table 1 has two columns and three rows and pairs the weld quality classes B, C and D of GB/T 19418 with the acceptance levels 1, 2 and 3 of GB/T 26952 and GB/T 26953.

6 Components

6.1 The safety factor of a lifting chain used on an attachment shall be not lower than 5. 6.2 Cast hooks shall not be used; where the conditions of use or the operating method could make the load come off the hook unintentionally, a hook with a locking device shall be used; defects in a forged hook shall not be repaired by welding. A forged hook shall be replaced when it shows cracks, when the opening dimension or the measured length exceeds the basic dimension before use by more than 10 %, when the twist angle of the hook body exceeds 10°, when the shank shows plastic deformation, when the wear exceeds 5 % of the basic dimension, or when corrosion of the shank diameter is greater than 5 % of the basic dimension or the thread is corroded.

6.3 Sliding bearing parts that lubricate, resist wear or separate surfaces inside a mechanism shall be adequately wear resistant, and shall be scrapped if they show plastic deformation, cracks, ageing, movement interference caused by wear, or wear reaching 40 % of the original thickness or a maximum wear greater than 5 mm.

6.4 Transmission gears and gear rims whose scrapping criteria are not given in the instruction handbook shall be scrapped in any of the following cases: plastic deformation of the teeth raising the peak of the tooth flank more than 20 % of the module above the theoretical tooth form, or lowering the valley of the tooth flank more than 20 % of the module below it; tooth breakage of at least one fifth of the face width or a tooth crack of at least one eighth of the face width; pitting reaching 50 % of the working area of the tooth flank, or a largest pit dimension of 0.2 module over more than 20 % of the flank, or, for other mechanisms, a pit depth of 0.15 module over 20 % of the flank; scuffing reaching 20 % of the working flank area with scuffing grooves 0.1 module deep; flaking judged by the same criteria as pitting; and a total wear on the two sides of the tooth root of 0.15 module.

6.5 The material of the main load bearing connecting pins should be 45 steel meeting GB/T 699 or 40Cr, 35CrMo or 42CrMo meeting GB/T 3077, and shall be heat treated as necessary. Pins and bushes shall be scrapped if they show plastic deformation, cracks, a fit clearance between pin and bush that has grown so much that the relative movement of the members can no longer be met, or wear of the pin end face reaching 5 % of the original size.

7 Hydraulic system

7.1 The design and installation of the hydraulic system shall meet GB/T 3766. 7.2 The set pressure of the relief valve shall be not more than 1.1 times the maximum working pressure of the system. 7.3 The system shall include a measure or a device that prevents the hydraulic motor from overspeeding under an external load. 7.4 The maximum temperature rise of the hydraulic oil in service shall not impair the safety performance of the attachment. 7.5 The manual valves shall offer an even resistance when operated, without shock and without jumping.

7.6 Hoses, tubes and fittings shall withstand three times the rated working pressure of the hydraulic circuit for 1 min without bursting and without abnormal behaviour. Tubes and hoses shall be positioned reliably and fixed where necessary, so that the risk of damage from wear, sharp corners and other causes is kept as small as possible. 7.7 The system shall be designed so that no uncontrolled movement of the attachment occurs if the power supply fails or is interrupted.

7.8 An attachment that clamps the load by power shall be designed so that, when the manual control of the truck is in the neutral position or the power supply system of the attachment fails, the designed maximum load stays clamped automatically for at least 10 min. 7.9 Where the hydraulic system of the attachment is connected to that of the truck, the two systems shall be compatible. 7.10 The inlet and outlet connections of the hydraulic circuit of the attachment shall be clearly marked.

8 Electrical system

8.1 Suitable measures shall be taken on the electrical equipment to prevent circuit faults caused by overload or shock from leading to a hazard. 8.2 The overcurrent protection element shall be able to break the maximum overcurrent without causing a fire hazard. 8.3 All conductors shall be effectively insulated and shall be routed with suitable measures against damage from environmental factors and from mechanical stresses and other external actions.

8.4 The electrical system shall be designed to match the electrical system of the truck, so that the attachment works safely whether it supplies its own power or draws power from the truck; where a power connector is used, it shall prevent reversed polarity. 8.5 The electrical system shall be designed ergonomically, so that hazards during installation, use, inspection and maintenance can be prevented. 8.6 The degree of protection of the enclosure of the electrical equipment shall be not lower than IP54 of GB/T 4208-2017.

9 Control and operating system

9.1 The control and operating system shall be designed and laid out so that incorrect operation is avoided and the attachment runs safely and reliably. 9.2 The design shall pay attention to potentially hazardous working situations that cannot be foreseen, such as uncontrolled changes of speed, moving parts that cannot be stopped, or a safety device that is obstructed. 9.3 When power is restored after an interruption, the attachment shall be prevented from restarting by itself.

10 Information for use

10.1 Every attachment supplied to a user shall be accompanied by an instruction handbook, which shall include operating instructions and periodic maintenance instructions and shall point out all the hazards that have been identified.

10.2 The handbook shall contain at least the name and address of the manufacturer; the name of the attachment, for example a bale clamp or a paper roll clamp; assembly precautions, illustrated where necessary; the basic electrical or hydraulic circuit diagrams; a description of the safety devices and the warning signs; the intended use of the attachment and examples of hazardous misuse; instructions for safe operation, such as changing the attachment; warnings about hazards that may arise in use, including crushing and shearing; the lifting points of a detachable attachment; the inspection and maintenance intervals and items; instructions on what to do in the event of a fault; a description of the functional movements and the interfaces of the attachment; and the maximum oil supply pressure and flow rate of the attachment.

11 Marking

11.1 A clear and permanent nameplate meeting the dimensions of GB/T 13306 shall be fitted in a conspicuous position on the attachment where it will not easily be damaged, and shall carry at least the name and address of the manufacturer of the attachment, the product model, the product number and year of manufacture, the mass of the attachment, the distance from the centre of gravity of the attachment to its mounting face on the truck, the rated lifting capacity, the maximum working pressure, the load centre distance, the lost load centre distance, that is the horizontal displacement of the standard load centre that fitting a detachable attachment to the truck may produce, and a statement that the lifting capacity of the truck is to match the attachment.

11.2 Safety signs and hazard pictorials meeting GB/T 26560 shall be fitted in a conspicuous position on the attachment, including at least a do not stand on sign, a caution sign and a do not reach in sign.

12 Operation of the attachment

12.1 The general rules for safe operation cover the operator, the working routine and the load. The operator shall be trained on the attachment and shall operate and use it according to the instruction handbooks, shall not carry out other work that distracts attention, shall not operate the attachment when physically or mentally unfit, shall watch the surroundings and obey a stop signal given by anyone, shall lower the attachment to the ground before leaving the truck, and shall report an attachment that needs adjustment or repair to the management and tell the operator on the next shift.

At the start of every shift the operator shall check the action of all the control devices and have them adjusted or repaired before the attachment is used if they do not act correctly, and shall also check the pipe joints and the cylinder rod ends for leaks, operate the attachment without load before loading it so as to expel the air from the hydraulic lines, and check the control levers to see that the movements correspond to the required functions.

The load and the movements are also governed: the mass of the load shall not exceed the capacity given on the rating plate of the truck and attachment combination, the load shall not be picked up markedly off centre, the attachment shall not strike other objects, side shift shall be speed limited and slewing slow once the load is raised, and during stacking the load shall not be tilted forward before it is above the stack. During push work the load is pushed out while the truck reverses and during pull work the load is pulled back while the truck moves forward, the two speeds being coordinated; with an attachment that has a backrest the load should not be higher than the backrest; the attachment shall work smoothly and freely without sticking.

If the hydraulic system shows abnormal noise, a rapid rise in oil temperature, abnormal cylinder pressure or return pressure, or oil leakage, the truck shall be stopped at once, examined and the cause removed. Whether the truck is loaded or not, nobody shall pass under or stand under a raised attachment or other lifting part; during operation no part of the body, such as an arm, a leg or the head, shall be placed inside the mast mechanism or other moving parts of the truck, and nobody shall climb on or touch parts of the industrial truck that move relative to one another, for example a reach carriage, a working device or a load handling device.

12.2 Before the attachment handles a load, its mass shall be confirmed by whatever means are available; goods outside the intended use of the attachment shall not be handled; and a load may be handled only when the attachment can pick it up, clamp it where a clamping function exists, and hold it reliably.

13 Inspection and maintenance of the attachment

13.1.1 Inspection of the attachment is divided into daily inspection and periodic inspection, the period of the periodic inspection being generally monthly, half yearly and yearly. 13.1.2 The daily inspection is made at the start of every shift and consists of visual or functional checks, chosen to suit the type of attachment, of the legibility of the nameplate and of whether the safety signs and hazard pictorials have come off, of the engagement of the hooks with adjustment where necessary, of leakage in the hydraulic system, of deformation, sharpening and wear of the load contact faces, of the effective end stop of the device that prevents unintentional detachment, of loose or missing nuts, of the electrical equipment, which shall be free of lubricating oil, grease, water and dust, of foreign matter, which is cleared away, of the correct action of all control devices and of the other functional devices.

13.1.3 The monthly inspection is made once a month, or at the interval laid down by the manufacturer or set from the actual working conditions of the attachment, and adds to the daily items, as appropriate to the type of attachment, the flexibility of the kinematic pairs with adjustment where necessary, deformation or cracking of pins and connecting rods, ageing or damage of hoses and leakage of hydraulic oil, the working of the fork pins and of the fork stops on both sides of the upper crossbeam, wear or damage of the oil pipes, and wear of the rubber blocks.

13.1.4 The half yearly inspection is made every six months, or at the interval laid down by the manufacturer or set from the actual working conditions, and adds to the daily and monthly items, as appropriate to the type of attachment, the lubrication of the slewing bearing, the bearings and the sliders, the oil level of the gear oil in the reducer, wear of hooks and shackles, the running of the kinematic pairs, the pressure holding of the hydraulic system, wear and cracking of the structural parts including the welds, and loose or missing screws.

13.1.5 The yearly inspection is made once a year, or at the interval laid down by the manufacturer or set from the actual working conditions, and adds to the daily, monthly and half yearly items a check, appropriate to the type of attachment, of the overall condition and of whether the key mating parts, the hydraulic components and the drive components are in order.

13.2.1 A planned maintenance programme shall be drawn up on the basis of the recommendations of the manufacturer of the attachment and shall be carried out; the content is mainly cleaning, lubrication, tightening and adjustment. Moving parts that need lubrication shall be lubricated at regular intervals and the supply of the lubrication system shall be checked, the lubrication points, the lubrication service level and the form of lubrication laid down by the manufacturer being followed strictly; where no automatic lubrication system is fitted, lubrication shall be carried out with the machine stopped. Bolts, nuts and other threaded fasteners shall be checked at regular intervals against the tightening torque laid down by the manufacturer.

13.2.2 Unplanned maintenance is decided after a failure, or from the results of the daily and periodic inspections, for the defects found, and is then carried out. Where a part has to be adjusted during unplanned maintenance, the adjustment items shall include functional operation and control system operation. Where the metal structure has to be repaired by welding and reinforcement, the quality after repair shall meet the relevant provisions of 4.3; the original refers here to 4.3, which is the clause on the permissible deviation of the mass of the attachment. Main parts used as replacements shall meet the technical requirements laid down by the manufacturer, and substitute parts and substitute materials may be used only with the agreement of the manufacturer.

13.2.3 Before the attachment is inspected or maintained the following precautions are taken: the truck carrying the attachment is driven to a designated position; a warning notice board is put up; the inspection and maintenance staff are equipped with personal protective equipment, for example protective footwear, a safety helmet and protective goggles; any load on the attachment is removed; the truck and the attachment are not operated during the inspection and maintenance except on the instruction of a designated person; the parking brake is applied and wedges are placed under the wheels to prevent the truck from moving unintentionally; the mast is secured against unintended tilting and lowering; all control devices are put in the neutral or idle position; and the pressure is released before a pressurized device is dismantled.

13.2.4 After the inspection and maintenance, all the safety devices shall be refitted and adjusted and shall reach their proper function before the attachment is put back into use.