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45 4.9.6 Lubrication 4.11.3 Process Trackside lubrication is an appropriate way to reduce noise The researchers recommend that infrastructure mainte- and wear on curves and help minimize the risk of derailment nance be based on the following principles: on switches and crossings; however, it should only be used on sections of track where such issues arise. Provision of maintenance manuals, Training of staff, Use of adequate tools and equipment, 4.10 Operation of LFLRVs Scheduled preventive maintenance, The following guidelines are for any U.S. or Canadian sys- Timely corrective action, tem introducing LFLRVs to minimize performance issues: Good-quality maintenance records, and Maintenance tolerances. Staff training should include issues peculiar to LFLRV operation, including an appreciation of the risks of not These principles apply generally but are even more important adopting changed practices. This training should include in minimizing performance issues associated with LFLRVs. operators, vehicle and track maintenance staff, and super- visory staff. Provision of Maintenance Manuals Procedures should be in place in order to recognize and deal with the early symptoms of performance issues, Using good-quality infrastructure maintenance manuals can (e.g., wheel and rail wear and noise), and to allow man- overcome many issues. Each system needs to provide such man- agement to take early corrective action while minimizing uals so as to address system-specific situations. For example, disruption. even though track workers may have all the information and Operators should avoid vehicle jerking and maintain con- training needed to determine what needs to be done and to cal- stant speed on curves, only accelerating when the curve has culate the tolerances that apply, workers are much more likely to passed. This is particularly important as a means of achiev- do the work properly if all requirements are set down in one ing ride comfort on LFLRVs. place in an easy-to-use document.A consistent approach, so that If LFLRVs need to operate at slower speeds than other vehi- everyone involved in track maintenance understands their roles cles in the fleet, the operators need to be fully aware of this. and responsibilities, is also needed. The act of creating an infra- structure maintenance manual ensures that the transit author- ity anticipates issues that might cause issues and manages them. 4.11 Infrastructure Maintenance Where the maintainer is not the transit authority, the lat- Standards ter should monitor the process sufficiently so as to ensure that 4.11.1 Who Applies These? the performance requirements are being met in an optimized way (e.g., the transit system has not observed the guidelines Maintenance of track is often carried out by the transit sys- and, as a result, its vehicles are suffering excessive wheel wear). tem, although it is quite common for it to be performed An independent body may perform this audit. under a maintenance contract or, in the case of new infra- Manuals should be updated periodically as experience is structure, by the supplier. In these circumstances, the main- gained and should incorporate clear schedules for periodic tainer must fully understand the issues associated with maintenance and procedures for dealing with different levels maintaining track in a suitable condition for the LFLRVs of issues that might require corrective action. operated on it. Track standards assumed by the vehicle sup- plier when vehicles were supplied need to be followed subse- quently or problems will occur. A process for managing the Training of Staff interface between vehicles and track at the contract stage Maintenance staff need training to maintain infrastructure should cover this. to the new guidelines that might be required for LFLRVs. Such training should be part of the training normally pro- 4.11.2 Where Do They Apply? vided to maintenance staff, rather than as a separate course. Any maintenance contract should require the maintainer to Infrastructure maintenance guidelines will apply in the sit- provide this training both for existing staff and for new staff. uations (A to E) described in Section 4.1. In Situations A, C, Training will generally be based on the material in the and D, it may be necessary to implement some of these rec- manuals and include both classroom and on-track training. ommendations retroactively. At the end of any training, trainees should be tested to ensure

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46 that they meet the required standard and their ongoing per- infrastructure maintenance manual. Also, faults should be formance should be monitored. If any maintenance proce- detected during the course of scheduled service running. dures change because of experience, new practice, and so forth, refresher courses will be necessary. Timely Corrective Action Operators should be trained to report faults that they detect when driving vehicles in regular service, because this Where an issue is identified or emerges, action must be taken an important source of feedback on condition. to avoid accidents, damage, or objectionable performance issues. The seriousness of the issue should be determined and then graded on a scale of action that might range from no action Tools and Test Equipment but correct by the next periodic inspection to situations that The tools and test equipment needed to meet the mini- might require operational restrictions to a complete stoppage. mum requirements of this guidance are as follows: Good-Quality Maintenance Records Profile measurement systems, Track measurement cars, and Records need to be kept for the maintenance work carried "Mine sweepers" to detect track anomalies. out on the track and should consist of a linear record of each section of the route and for each infrastructure item (e.g., switches), showing details of components, measurements Scheduled Preventive Maintenance taken, inspections made, and work carried out. These records LFLRV performance will depend partly on maintaining should be revised whenever work takes place and be available key track parameters within relatively tight tolerances; there- to everyone who needs access to them. fore, these tolerances must be monitored as part of a sched- uled preventive maintenance program. The key parameters to Maintenance Tolerances be checked include rail profile and alignment, switches and crossings dimensions (including gauge face wear), and avail- The maintenance manual should include maintenance toler- ability of trackside lubrication. The periodicity and methods ances for all the features of the infrastructure where LFLRVs are of inspection should be determined and incorporated in the operated. Some possible tolerances are shown in Table 4-11 as Table 4-11. Suggested maintenance tolerances. Parameter Tolerance Note Track gauge + 3/8 inch, -1/4 inch (+9.5 mm, -6Example of a standard that mm) from design has been used in the U.S. where LFLRVs are in use. Track wear Top wear 25 mm (0.975 inch), side German standard, which wear 20 mm (13/16 inch). accommodates IRWs but is not unduly harsh in the U.S. Horizontal alignment APTA 8.3 Table 5 See Section 3.6.6 Lateral alignment APTA 8.4 Table 6 A check is needed that the Track twist APTA 8.4 Table 6 lateral alignment variations Super-elevation APTA 8.4 Table 6 provide sufficient clearances for LFLRVs. Cross level Not more than 11/4 inches (32 Tighter than APTA 8.4 Table mm) variation in 62 ft (8.9 m) 6 length. Track structure APTA 9 and 1? 3.5 Standards must be developed so that the requirements listed above are met. Rail-end mismatch None should exist. Welded rail should always be used. Restraining rail guard face gage 5 mm (0.2 inch) variation Tighter than APTA 11.2 Table 12. Minimum flangeway in S&C This may be less than the 11/4 IRWs are an "exception," see inches (38mm) in APTA 12.1.2 APTA 1.3 Flangeway depth APTA 12.3.1 and 13.4.2 apply. Condition of S&C It may be necessary to adopt See also APTA 13.7 tighter standards than APTA recommends. Gauge face wear angle +3o to match wheel limits