Section 2 Passenger lifts

2.1.1 This Section applies to electric and hydraulic powered lifts permanently installed in ships and employing an enclosed car suspended by ropes/chains or supported by hydraulic cylinders and running between rigid guides for the transfer of persons, or persons and goods, between the decks. It is recommended that the rated speed does not exceed 1,0 m/s and is to be limited to 1,0 m/s for hydraulic lifts and 0,63 m/s for positive drive lifts. Traction drive lifts designed for a higher rated speed will be specially considered.

2.1.2 The lift is to comply with the requirements of a recognised National or International Standard, e.g. EN 81, ISO 8383 and any requirements of the National Authority of the country of registration and the requirements of this Section. Deviations from these Standards are to be stated by the manufacturer and require approval by LR and the Flag State.

2.1.3 The relevant design criteria, such as rated load, minimum stopping distance, buffer stroke, type of hoisting drive, type of safety gear and buffer are to be clearly specified in all lift submissions. For guidance regarding the submission of relevant plans and information required, see Ch 1, 3.4 Shiplifts. The certificates for the safety components are to be submitted for consideration.

2.1.4 The lift is to be designed such that it can be stowed, either manually or automatically, in the event of the specified operational conditions being exceeded.

2.1.5 For the operating conditions, the lift is to be designed with respect to the following forces:

1. Self-weight of car and counterweight;

2. Rated load;

3. Dynamic forces due to lift motion; and

4. Forces due to ship motion and static inclination.

2.1.6 For the stowed condition, the lift is to be designed with respect to the following forces:

1. Self-weight of car and counterweight; and

2. Forces due to ship motion and static inclination.

2.1.7 For the safety device operation or the car striking the buffers, the lift is to be designed with respect to the following forces:

1. Self-weight of the car and counterweight;

2. Rated load;

3. Dynamic forces due to lift motion; and

4. Forces due to static vessel inclination.

2.1.8 Lifts are to be constructed of steel which complies with the requirements of Ch 1, 1.6 Materials and fabrication and Ch 11 Materials and Fabrication. Proposals to use materials other than steel will be specially considered. The fabrication is to be in compliance with Ch 11, 2 Fabrication of classed lifting appliances or Ch 11, 3 Fabrication of certified lifting appliances.

2.1.9 The selected steel grade is to provide adequate assurance against brittle fracture. The steel is to comply with the Charpy V-notch impact test requirements given in Ch 11, 1.2 General material requirements 1.2.2. Alternative proposals in respect of the notch toughness characteristics of the materials will be considered when the environmental condition of the particular installation is such that there is a low probability of low temperatures.

2.1.10 The required documentation for materials used for the construction of classed and certified lifts is defined in Ch 11, 4 Material documentation for certified and classed lifting appliances.

2.2.1 The self-weight load, L _w, is the load imposed on the hoisting mechanism by the weight of the permanent components of the lift car structure and machinery.

2.2.2 The rated load, L _c, is the load imposed on the lift car by the passengers and is to be not less than that obtained from Table 7.2.1 Rated load. The load L _c is to be evenly distributed over those three quarters of the car being in the most unfavourable position.

2.2.3 Where lifts are mainly intended to carry goods which are generally accompanied by persons, the design is to take into account the load to be carried (including eccentricities) and the weight of any handling device (if applicable) which may enter the car in addition to the requirements of Table 7.2.1 Rated load.

2.3.1 The dynamic forces due to the operation of the lift are to be taken into account by multiplying the self-weight and rated load by an impact factor, k, which is to be obtained from Table 7.2.2 Impact factors.

2.3.2 The rated speed, minimum stopping distance and buffer stroke are to be obtained from the lift specification to which the lift is constructed. Figure 7.2.1 Buffer strokes provides typical buffer strokes.

2.4.1 Passenger lifts, their associated machinery and structure are to be designed to operate at sea with respect to the following conditions:

1. Roll: ±10°, with 10-second period.

2. Pitch: ±7,5°, with 7-second period.

2.4.2 In addition to the operational conditions, the lift, associated machinery and structure are to be designed to withstand the forces resulting from consideration of the following conditions when in stowed condition:

1. Roll: ±22,5°, with 10-second period.

2. Pitch: ±7,5°, with 7-second period.

3. Heave: Amplitude = 0,0125L with 10-second period.

   where

   L

   =

   is the Rule length of the ship (see Pt 3, Ch 1 General of the Rules for Ships).

2.4.3 The above periods apply if no actual ship-specific data is available. If the ship characteristics are known, the periods may be calculated using Ch 4, 2.11 Forces due to ship motion 2.11.4. The forces due to ship motion are to be calculated in accordance with Ch 4, 2.11 Forces due to ship motion 2.11.5 and Ch 4, 2.11 Forces due to ship motion 2.11.6. For the stowage condition as in Ch 7, 2.4 Static and dynamic forces due to ship motion 2.4.2, the angles can also be calculated as per Ch 4, 2.11 Forces due to ship motion 2.11.4 if the ship characteristics are known.

2.4.4 The forces due to ship motion are to be applied at the centre of the gravity of the car and counterweight and centre of the gravity of the rated load of the car in all three directions: neutral to deck (F _N), in transverse (F _T) and longitudinal direction (F _L), and are to be considered for all relevant stress proofs.

2.5.1 The lift and its associated mechanism and structure are to be considered with respect to design loads resulting from the following conditions:

1. Case 1: The lift in the ‘operating condition’ is to be considered with respect to forces due to ship motion resulting from the conditions defined in Ch 7, 2.4 Static and dynamic forces due to ship motion 2.4.1 and Ch 7, 2.4 Static and dynamic forces due to ship motion 2.4.3, together with the normal to deck components of dead load and live load multiplied by the factor, k ₂, to be obtained from Ch 7, 2.3 Dynamic forces due to lift motion 2.3.1. This is represented by the following expression:

   k ₂ (F _N,Lw + F _N,Lc) + F _T,Lw + F _T,Lc + F _L,Lw + F _L,Lc

   where

   F N,Lw

   =

   normal to deck force resulting from selfweight L w

   F N,Lc

   =

   normal to deck force resulting from rated load L c

   F T,Lw

   =

   transverse force due to roll resulting from L w

   F T,Lc

   =

   transverse force due to roll resulting from L c

   F L,Lw

   =

   longitudinal force due to pitch resulting from L w

   F L,Lc

   =

   longitudinal force due to pitch resulting from L c

2. Case 2: The lift in the ‘stowed condition’ (self-weight only) is to be considered with respect to the forces resulting from the accelerations due to the ship's motion as defined in Ch 7, 2.4 Static and dynamic forces due to ship motion 2.4.2 and Ch 7, 2.4 Static and dynamic forces due to ship motion 2.4.3. This is represented by the following expression:

   F _N,Lw + F _T,Lw + F _L,Lw

3. Case 3: The lift in the exceptional condition, e.g. buffer stroke, safety device operation or rupture valve operation, is to be considered with respect to the forces resulting from the inclinations due to ship motions, as defined in Ch 7, 2.4 Static and dynamic forces due to ship motion 2.4.1, together with the normal to deck components of dead load and live load multiplied by the factor k ₁ which is to be obtained from Ch 7, 2.3 Dynamic forces due to lift motion 2.3.1. This is represented by the following expression:

   k ₁ (F _stat,N,Lw+ F _stat,N,Lc) + F _stat,T,Lw + F _stat,T,Lc + F _stat,L,Lw + F _stat,L,Lc

   where

   F stat,N,Lw

   =

   normal to deck force resulting from static component of self-weight L w

   F stat,N,Lc

   =

   normal to deck force resulting from static component of the rated load L c

   F stat,T,Lw

   =

   transverse force resulting from the static component of roll angle resulting from L w

   F stat,T,Lc

   =

   transverse force resulting from the static component of roll angle resulting from L c

   F stat,L,Lw

   =

   longitudinal force resulting from the static component of the pitch angle due to L w

   F stat,L,Lc

   =

   longitudinal force resulting from the static component of the pitch angle due to L c.

2.6.1 The allowable stress, σ_a, is to be taken as the failure stress of the component concerned multiplied by a stress factor, F, which depends on the load case considered. The allowable stress is given by the general expression:

where

2.6.2 The stress factor, F, for steels in which σ_y/σ_u ≤0,85 is given in Table 7.2.3 Stress factor, F

where

2.6.3 For steel with σ_y/σ_u > 0,85, the allowable stress is to be derived from the following expression:

where

2.6.4 Steels with σ_y/σ_u > 0,94 are, generally, not acceptable and need to be specially considered.

2.6.5 The failure stress for the elastic modes of failure are given in Table 7.2.4 Failure stress.

2.6.6 For components subjected to combined stresses, the following allowable stress criteria are to be used:

1. σ_xx ≤ σ_a

2. σ_yy ≤ σ_a

3. τ_o ≤ τ_a

4. 

   where

   σxx	=	applied stress in x direction
   σyy	=	applied stress in y direction
   τo	=	applied shear stress.

2.6.7 The allowable bearing stress for rotatable and fitted pin connections are to be taken as σ_a.br = 0,8σ_y for Case 1 and Case 2 and σ_a.br = 1,0σ_y for Case 3. The allowable bearing stress for rotatable pin connections with dynamics or loose fit will be specially considered. Ball and roller bearings are to be in accordance with a recognised National or International Standard. The allowable bearing stress for other surface-tosurface contact (pressures) is to be taken as in Ch 7, 2.6 Allowable stresses in combination with Table 7.2.4 Failure stress

2.6.8 In the case where the structural analysis is carried out by means of detailed finite element models, higher allowable stresses can be applied as follows:

1. σ_xx.FE ≤ 1,1σ_a

2. σ_yy.FE ≤ 1,1σ_a

3. τ_o.FE ≤ 1,1τ_a

4. σ_e.FE ≤ 1,1² σ_a

where

Higher allowable stresses, as defined above, can only be applied if the actual stresses are localised. In the case where the actual stresses can also be calculated by means of analytical methods, these higher allowable stresses are not applicable and Ch 7, 2.6 Allowable stresses 2.6.1 are to be applied.

2.6.9 The allowable stress for plate buckling failure is to be taken as the critical buckling stress of the component concerned multiplied by the stress factor, F, as defined in Table 7.2.4 Failure stress. For the critical buckling stress see Ch 4, 2.21 Allowable stress – Plate buckling failure.

2.7.1 The deflection of the car structural members is not to exceed l/600 mm.

2.7.2 The maximum permissible deflections for guide rails are as follows:

1. 5,0 mm for guide rails on which safety gears are operating.

2. 10,0 mm for guide rails without safety gears operating.

2.7.3 The car walls or doors in their closed position are to be able to resist without permanent deformation or elastic deformation greater than 15 mm a force of 300 N evenly distributed over a circular or square area of 500 mm², applied parallel to the deck from the inside towards the outside of the car. The doors are to be capable of operating normally after being subjected to this load.

2.7.4 The car roof is to withstand, without permanent deformation, a force of 2000 N representing two persons applied at any position, normal to deck and distributed over an area of 200 x 200 mm².

2.8.1 At least two steel guide rails are to be installed for each car and each counterweight or balance weight. The surface finish of the guide rails is to be sufficiently smooth to allow free running of the car and each counterweight.

2.8.2 The guide rails, their joints and attachments are to be designed to resist forces resulting from the load combinations as in Ch 7, 2.5 Load combinations.

2.8.3 The allowable stress for compression and bending in the guide rails is to be calculated in accordance with the methods described in Ch 4, 2.18 Allowable stress – Compression, torsional and bending members

2.9.1 The car and counterweight are to be provided with a safety gear capable of operating only in a downward direction by gripping the guide rails. It is to be capable of stopping the fully laden car or counterweight at the tripping speed of the overspeed governor, even if the suspension device breaks. The car safety gear is to be tripped by an overspeed governor, but the counterweight safety gear may be tripped by failure of the suspension gear or by a safety rope, in case the rated speed does not exceed 1,0 m/s.

2.9.2 The car safety gear shall be:

1. Of the progressive type if the rated speed of the life exceeds 1,0 m/s.

   and may be:

2. Of the instantaneous type with buffered effect if the rated speed is not in excess of 1,0 m/s.

3. Of the instantaneous type if the rated speed does not exceed 0,63 m/s.

For hydraulic lifts, safety devices such as restrictors and rupture valves shall be provided.

2.9.3 The counterweight safety gear is to be of the instantaneous type if the rated speed is not in excess of 1,0 m/s and is to be of the instantaneous type with buffered effect in the case of rated speeds in excess of 1,0 m/s.

2.9.4 The jaws of safety devices are not to be used as guide shoes.

2.10.1 Tripping of the overspeed governors for the car safety gear is to occur at a speed of at least 115 per cent of the rated speed and less than the following:

1. 0,8 m/s for instantaneous safety gears except for the captive roller type;

2. 1,0 m/s for safety gears of the captive roller type;

3. 1,5 m/s for instantaneous safety gear with buffered effect and for progressive safety gear used for rated speeds not exceeding 1,0 m/s; or

4. 1,25v + 0,25/v for progressive safety gear for rated speeds exceeding 1,0 m/s,

   where

   v

   =

   rated speed, in m/s.

2.10.2 The tripping speed of an overspeed governor for a counterweight safety gear is to be higher than that for the car safety gear but is not to exceed it by more than 10 per cent.

2.10.3 The force exerted by the overspeed governor when tripped is to be not less than the greater of:

1. 300 N; or

2. twice the force necessary to engage the safety gear.

2.10.4 The breaking load of the overspeed governor operating rope is to have a safety factor of 8:1 with respect to the force required to operate the safety gear. The rope is to be not less than 6,0 mm diameter and the ratio of the bottom of the sheave groove diameter to rope diameter is to be not less than 30:1.

2.11.1 The car and counterweight are to be provided with buffers at their bottom limit of travel. When the car is resting on its fully compressed buffers, the free distance between the pit floor and the lower extension of the car floor is to be at least 0,5 m.

2.11.2 Energy accumulation type buffers are only to be used if the rated speed of the lift does not exceed 1,0 m/s. Energy accumulation type buffers with buffered return movement are to be used only if the rated speed of the lift does not exceed 1,6 m/s. Energy dissipation type buffers can be used at any rated speed of the lift.

2.11.3 Where energy accumulation type buffers with linear characteristics are used, the total possible stroke of the buffers are to be at least equal to twice the gravity stopping distance corresponding to 115 per cent of the rated speed, i.e.:

where

Buffers are to be designed for the above stroke, under a static load between 2,5 and 4,0 times the self-weight of the car plus its rated load or the self-weight of the counterweight.

2.11.4 Where non-linear energy accumulation type buffers are used, the deceleration due to the buffers acting on a freefalling car (with the rated load in it and 115 per cent of the rated speed) is not to exceed 1,0g on average. The maximum deceleration is not to exceed 2,5g and the return speed of the car is not to exceed 1 m/s.

2.11.5 No permanent deformation after buffer contact is permitted.

2.12.1 Each lift is to have at least one engine of its own. The hoisting arrangements may consist of:

1. Traction drive using sheaves and ropes; or

2. Positive drive, consisting of:

   1. Drum and rope without counterweight; or

   2. Sprocket and chain.

3. Hydraulic cylinders, which are either directly or indirectly acting.

2.12.2 The ratio of the pitch diameter of sheaves, pulleys or drums and the rope diameter of the suspension rope is to be at least 39:1. Where drum drive is used, the drum is to be grooved and the fleet angle of the rope in relation to the groove is not to be greater than 4° either side of the groove axis.

2.12.3 Not more than one layer of rope is to be wound on the drum and when the car rests on its fully compressed buffers, one and a half turns of rope are to remain in the grooves.

2.12.4 The safety factor of the means of suspension, defined as the ratio of minimum breaking load of the rope/chain to the maximum load on the rope/chain when the car is at its lowest level and subjected to its rated load, is to be not less than:

1. 12:1 in the case of traction drive with three ropes or more.

2. 16:1 in the case of traction drive with two ropes.

3. 12:1 in the case of drum drive or indirect hydraulic lifts.

4. 10:1 in the case of suspension chains.

2.12.5 A device is to be fitted at one end of the hoisting arrangement to equalise the tension in the ropes or chains. In the case of a two rope/chain suspension, a device is to be fitted which stops the lift in the case of abnormal relative extension of one rope/chain. Positive drive lifts are to have a slack rope/chain detection device. If more than one hydraulic cylinder is provided, they are to be hydraulically connected to ensure pressure and compression force equilibrium in the hydraulic cylinder.

2.12.6 Where compensating ropes are used, the ratio between the pitch sheave groove diameter and diameter of the rope is to be not less than 30:1.

2.12.7 For traction sheaves, pulleys and sprockets, protection is to be provided to avoid:

1. Bodily injury.

2. The ropes/chains leaving the pulleys/sprockets, if slack.

3. The introduction of objects between ropes/chains and pulleys/sprockets.

2.12.8 The junction between the rope and the rope termination is to be able to resist at least 80 per cent of the minimum breaking load of the rope.

2.12.9 The lift is to be provided with a braking system which operates automatically in the event of loss of the mains power supply or in the event of the loss of the supply to control circuits. Furthermore, it is to be equipped with an emergency operation device either working manually or with means of emergency electrical operation.

2.13.1 In sections of the ship where the lift trunk is required to contribute against the spread of fire, the lift trunk and machinery spaces are to be completely enclosed, suitably ventilated and constructed to give fire protection in compliance with the requirements of SOLAS 1974, as amended.

2.13.2 Clearances around the car are also to be guarded or arranged to preclude the possibility of personnel falling between the car and trunk. In addition, when the counterweight rests on its fully compressed buffer, the free distance above the roof of the car is to be at least 0,75 m.

2.13.3 Only pipes and cables belonging to the lift may be installed in the trunk. Travelling cables are to be protected by an internally smooth metal trough which is to be provided with a slot having rounded edges to allow free passage of the cables leaving the lift car and be of sufficient width to allow passage of the free hanging loop of the travelling cable.

2.13.4 Where two or more lifts are fitted into one trunk, each car and its associated counterweight is to be separated by means of sheet steel over the full height of the trunk.

2.13.5 The lift trunk is not to be part of the ship's ventilation ducting but is to be ventilated by an independent system.

2.13.6 The trunk entrances are to be located to prevent the ingress of water or cargo into the trunk. The deck areas at entrances are to be non-slip and of approved material which will not readily ignite.

2.13.7 Where the lift is for the crew, the headroom of the trunk (the space above the car roof when the car is in its highest position) is to incorporate an escape hatch which opens outwards of at least 0,24 m² with a side length not less than 350 mm.

2.13.8 The floor of the pit is to be able to support the car buffer considering four times the static load being imposed by the mass of the fully laden car without permanent deformation. In addition, if accessible spaces do exist below the car, the counterweight or the balancing weight, the base of the pit is to be designed for an imposed load of at least 5 kN/m².

2.14.1 The car is to be constructed of steel or equivalent non-flammable material, have a non-slip floor and be provided with at least one handrail where access for persons is clearly available. A load plate is to be prominently displayed specifying the safe working load in persons and kilograms.

2.14.2 The car entrances are to be provided with doors of an imperforate type fitted with devices to prevent untimely opening and slamming. The clearance between the car and car door is to be not more than 6,0 mm.

2.14.3 Power operated doors are to be of the centre opening balanced type and manual doors of the two-panel centre opening type or concertina or telescopic type opening from one side only. Alternative arrangements which are considered to be of equivalent safety will be accepted. The effort needed to prevent the door from closing is not to exceed 150 N. Manual single sliding entrances of the concertina or telescopic type are to be fitted with devices to prevent slamming.

2.14.4 The car and counterweight are to be guided over their full travel, including overtravel and an independent guidance medium to limit car movement in the event of primary guidance failure.

2.14.5 Counterweights are to be constructed of steel or equivalent material and filler weights are to be securely clamped in position within steel frames. Concrete filler weights are not permitted. A suitable device is to be fitted to stop and support the counterweight in the event of rope failure.

2.14.6 Traction drive lifts are to incorporate a device to stop and support the car if:

1. When a start is initiated, the lift machine does not rotate.

2. The car or counterweight is stopped in a downwards movement by an obstruction which causes the ropes to slip on the driving pulley.

2.14.7 The device is to function in a time not greater than the lesser of the following values:

1. 45 seconds.

2. Time for the car to travel the full travel distance plus 10 seconds, with a minimum of 20 seconds if the full travel time is less than 10 seconds.

2.14.8 The device is not to affect either the inspection or electrical recall operation.

2.14.9 The lift is to be fitted with a device to prevent the lift operating in the event of overload in the car. The overload is defined as rated load plus 10 per cent with a minimum of rated load plus 75 kg.

2.15.1 Steel doors are to be fitted at all entrance stations. When closed, the doors are to provide fire resistance at least as effective as the trunk to which they are fitted.

2.15.2 Power operated doors are to be of the centre opening balanced type and manual doors of the two-panel centre opening type or concertina or telescopic type opening from one side only. Alternative arrangements which are considered to be of equivalent safety will be accepted. The effort needed to prevent the door from closing is not to exceed 150 N. Manual single sliding entrances of the concertina or telescopic type are to be fitted with devices to prevent slamming.

2.15.3 The doors, including their locks, are to have mechanical strength such that in the locked position they are to be able to resist, without permanent deformation or elastic deformation greater than 15 mm, a force of 300 N. The force is to be evenly distributed over an area of 500 mm² applied at right angles to the panel at any point on either face. The doors are to be capable of operating normally after being subjected to this load.

2.15.4 When the distance between consecutive landing doors exceeds 11 m, intermediate emergency doors are to be provided.

2.15.5 The horizontal distance between the sill of the car and the sill of the landing doors is not to exceed 35 mm.

2.16.1 To enable crew to escape independently, the trunk is to be fitted with a ladder over its entire length leading to the escape hatch in the headroom.

2.16.2 For lifts intended solely for passengers, a suitable ladder is to be provided to give access to the lift car roof from a landing door. Another is to be provided to give access into the car from the emergency opening in the car roof. These ladders are to be kept in a watchkeeping room or another room accessible to competent persons.

2.16.3 A trap door in the roof of the lift car with suitable access to it from the inside is to be provided with an opening of at least 0,24 m², having a side length not less than 350 mm. Where the lift is solely for passengers, the trap door is to be fitted with a mechanical lock which can only be operated from the outside. Where the lift is solely for crew, the trap door is to be fitted with a mechanical lock which can be operated from inside and outside the car. Alternative emergency evacuation arrangements, procedures or methods instead of a trap door will be specially considered.

2.16.4 For crew lifts, an escape hatch is to be provided in the headroom of the trunk. Opening the hatch from the outside is only to be possible by means of a special key which is to be kept in a box immediately by the hatch.

2.16.5 Notices in English, other languages and pictographs as necessary, describing the escape routine, are to be fixed in the following locations:

1. Inside the car.

2. On the car roof.

3. Inside the trunk, adjacent to every exit.