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40 in this research as influencing LFLRV performance signifi- A static measurement check, including use of wheel pro- cantly. The guidelines all apply to the center truck. file measuring gauges; Note 1: Wheel gauge is the distance between the contact A static loading test to check that the suspension char- areas on the rail sides of the flanges on a pair of wheels. It is acteristics are as expected; measured at a defined gauge line height for new wheels Dynamic running tests to ensure that the vehicle ride "wheelset." The figures shown apply to the center truck. meets the performance requirements under a range of Note 2: The wheel taper should be between 1 in 20 and loading conditions, including noise measurements both 1 in 40. The actual value should be determined by analysis inside and outside of the vehicle; and and will relate to the type of rail used and its inclination. A Checks on the condition of the wheel running surface variable taper will reduce the risk of two-point contact and and on the track at vulnerable locations (e.g., sharp provide better steering and possibly give better results. The curves and switches) to ensure that excessive wear is not objective is to keep contact at the rail center. occurring. Such checks will be made throughout an The selection of actual parameters can be based on a extended period of testing in service before the vehicles "decision tree" approach in order to develop an optimized are finally accepted. solution. This process constitutes "type testing." Acceptance tests shall also be arranged for subsequent deliveries of the same type and, as a minimum, the supplier should certify that each 4.5 Vehicle Selection Issues vehicle has been checked to ensure that the key parameters The transit system must check that the vehicles being sup- comply with those of the vehicle that was thoroughly tested. plied meet the requirements stated in Section 4.4 as part of a structured vehicle acceptance process. The following steps are 4.6 Vehicle Maintenance Guidelines envisaged: 4.6.1 Who Applies These? The supplier provides a response to the request for a proposal Maintenance of vehicles is often carried out by the transit that included the transit system's specification. The supplier's system, although it is quite common for it to be performed response should include the supplier's own specifications, under a maintenance contract by the supplier or another drawings, and other data. The transit system's assessor should agency. It is also usual for vehicle maintenance to be the scrutinize this information and carry out any necessary cal- responsibility of the supplier until the completion of an culations and investigations to ensure that the requirements acceptance process. are met. This should involve requests for further information In these circumstances, either the transit system must fully from the supplier as necessary. The process should also understand the issues associated with maintaining what may involve modeling vehicle performance, using an appropriate be a vehicle type that has not operated on the system before, or software package, and replicating the actual track conditions the contracted supplier or agency must be fully familiar with as closely as possible, although there may not always be suffi- the "peculiarities" of the system and the way it is operated. cient data available to do this thoroughly. The modeling Part of the process involves the supply of information by should either be carried out by the transit authority or by the the supplier so that staff are aware of maintenance require- supplier or the supplier's agent. In the latter case, the results ments. Part of the responsibility will, therefore, rest with the should be certified or checked by an independent body act- supplier, even where they are not involved in subsequent ing on behalf of the transit authority. maintenance activity. It is vital that suppliers provide infor- During the design and construction process, the supplier mation as part of their contract, in the form of manuals, may wish to modify the vehicle design. In this case, each training, and so forth, that take into account the level of modification should be acceptance-tested by the transit familiarity of the maintenance staff with their vehicles. This authority according to the guidance in Section 4.4 and will avoid the serious issues that can arise when a supplier using the dynamic modeling package if appropriate. delivers a vehicle to a new market that is unfamiliar with the When the first vehicle is ready to be delivered, the supplier technology. should certify that it now meets the agreed specifications and vehicle acceptance tests should take place. These tests 4.6.2 Where Do They Apply? should take place at either the supplier's own premises or elsewhere as appropriate. The main stages, in relation to Vehicle maintenance guidelines will apply in the situa- the issues described in Section 4.4, will be tions (A to E) described in Section 4.1. In Situation A, it may A visual check to see that the vehicle has all the features be necessary to implement some of these suggestions expected and that they are correctly assembled; retroactively.

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41 4.6.3 Process The user should normally only refer to one document, which is more convenient, saves time, and avoids poten- It is suggested that vehicle maintenance is based on the fol- tially serious confusion. lowing principles: Provision of high-quality technical manuals, Training of Staff Training of staff, Maintenance staff require training to maintain LFLRVs. Scheduled preventive maintenance, Where the maintenance is not to be carried out by the sup- Timely corrective action, and plier, the training should also be a part of the vehicle supply Good-quality maintenance records. contract and its successful completion should be part of the vehicle acceptance process. The training needs to be such that These principles will apply generally, but are even more it will allow some of the staff trained to train other new staff important in ensuring that performance issues associated subsequently. The maintainer has a responsibility to ensure with LFLRVs are minimized. that training is ongoing. Training will normally be based on the material in the manuals and include both classroom and on-vehicle training Provision of High-Quality Technical Manuals with fault finding and other exercises. At the conclusion of There have been cases where suppliers have provided any training, trainees should be tested so as to ensure that inadequate technical manuals with incomprehensible draw- they meet the required standard and their ongoing perform- ings, incomplete sections, text in foreign languages, text lifted ance should be monitored. If any maintenance procedures from subcontractor manuals without editing, and so forth. change because of experience, new components, and so forth, The contract for vehicle supply should include the provision refresher courses will be necessary. of adequate technical manuals, with procedures for fault finding, preventative and corrective maintenance, overhaul, Scheduled Preventive Maintenance and so forth. The manuals should also include illustrated parts lists. The format of the manuals should include photo- LFLRV performance will partly depend on maintaining graphs, diagrams and other material to readily identify com- key center truck parameters within relatively tight toler- ponents, and how testing, dismantling and re-assembly takes ances; therefore, vehicles must be monitored as part of a place. They should be divided into sections to cover different scheduled preventive maintenance program. Tolerances types of maintenance (e.g., electrical, mechanical, and diag- and other requirements, as listed in Table 4-6 and included nostic). Manuals should be supplied in both printed and in the supplier's manuals, need to be checked. Initially, digital format. checking should be performed relatively frequently until The manuals only need be provided where the suppliers "patterns" are discerned and the supplier's recommenda- are not carrying out maintenance; this applies to compo- tions for periodic inspection can either then be adopted or nents as well as vehicles as a whole. So for example if the cen- modified. The equipment and techniques used for taking ter trucks are to be maintained by the supplier, the manual critical measurements must do so accurately and properly should only cover how they are removed, replaced, and gage tolerances. tested. The maintainer should check and approve the manuals as Timely Corrective Action part of the vehicle acceptance process and the supplier's con- tract should ensure that the maintainer makes any appropri- Where an issue is identified or emerges it is essential that ate changes. the vehicle does not remain in service if this might cause dam- The maintainer, where this is not the supplier, should con- age, be dangerous or initiate performance issues. sider incorporating the manuals into its own maintenance documentation. This has several advantages: Good-Quality Maintenance Records The manuals can be simplified to cover only the require- Records need to be kept for each vehicle, each truck, and ments of the transit system. each component on the center truck and for other key com- Any special requirements of the system can be highlighted. ponents associated with LFLRV technology (e.g., roof- The maintenance schedules (see below) can be incorpo- mounted linkages and dampers). The records should show rated. measurements taken during programmed inspections and Experience can be incorporated. after major maintenance work and overhaul has taken place.