Centralised Lubrication System Components

Centralised Single Shot Oil Lubrication System Layout

While planning the system, the following procedures should be adopted :

• Ascertain lubrication points and find out the areas to be lubricated at corresponding lubrication points of machine.
• Select dosage of lubrication on each point. For this purpose, the basic rule is that per shot, a film of min. 25 micron thickness shall be formed over the area to be lubricated for automatic system and 50 micron for hand pumps. This is applicable for frequency of one hour. However, the volume is normally increased considering factors like; shock loading, quality and material of surfaces, service conditions, extra high speeds, heat & dust etc. Pure calculations are not enough and these are to be confirmed by experimental installation.
• Select metering cartridges according to lubricant dosage for each point.
• Sum up the dosages of metering cartridges for all the lubrication points.
• Depending upon machine requirement, finalise the type of pump.
• While selecting piston type pump (i.e. Hand operated and Pneumatically/Hydraulically operated Pump). Pump output per stroke shall be checked as per the following formula:
• PUMP OUTPUT = 1.25 x (A) + 1 CC x (B)
• (A) = Total Dosage of all metering cartridges used in the system.
• (B) = Length of primary flexible tubing in meter.
• In case pump output is less, select bigger size of pump.
• Select manifolds such that a manifold caters to all the lubrication points existing in the same vicinity.
• As regards layout of tubings and fittings it shall be so arranged that air which has entered the system may escape through lubrication points. For this purpose, following points are to be observed:
• (a) Preferably pump be installed at a place on the machine where oil level can be checked and refilling of oil can be done conveniently.
• (b) Main line (normally 6mm OD tube) from the pump should rise upward.
• (c) If main line is to be taken downward at any place, bifurcate the line such that one line goes upward also at the junction.
• (d) Last metering cartridge/cartridges in every branch of lubrication line must be upward.
• (e) Divide the main line into 2 or 3 branches near the pump, instead of routing one single line around the machine. This will minimise the tube length and give better appearance and ease of maintenance of system.
• (f) The secondary line (4mm OD tube) joining metering cartridges to lubrication points should be of minimum length. This is to avoid unnecessary time for filling secondary tube by lubrication impulse while commissioning lubrication system.
• (g) Connect outlet of each metering cartridge to one lubrication point only.
• (h) Use flexible tube (nylon or rubberised hose) for moving parts of the machine.
• (i) In case of lubrication point situated in the hot zone of the machine (or the zone where hot metal chips are likely to fall such as on the fixture), do not use nylon tube.
• While commissioning centralised lubrication on a machine, loosen the last plug/plugs screwed on the manifolds in each branch of main line. Give few lubrication impulses so that main line gets filled with the oil up to the end and oil starts leaking from the loosened plugs. Tight the plugs. Now give few lubrication impulses, until oil from all the metering cartridges reaches up-to lubrication points on the machine. Once this is achieved, the system becomes ready for use.
• As regards frequency of lubrication, it may vary from few minutes to few hours depending upon the kind and load of machines.