Some lubricants are applied by smearing them on the surfaces to be lubricated. You will most often use a tool (grease gun, oiler, or grease pump) especially designed to put the lubricant into the equipment through a lubrication fitting.
Grease is applied by a grease gun, or pump, through a nozzle that is designed to match the fitting. Although ordnance plants and repair shops have electrically or pneumatically powered equipment, you probably will have to depend on your own right arm for power to operate the lubricating equipment. Therefore, in this section we will discuss only the hand-powered lubricating equipment you are likely to use.
Hand-operated grease guns are of two types, depending on how they are loaded. To load one style, you remove a cap that comes off with the handle and stem (fig. 12-3) and fill the body with grease, using a paddle or spatula. As you might expect, this method of loading can be messy; it also exposes the lubricant to dirt and moisture. A faster and cleaner kind of gun (fig. 12-3, view A) is loaded by removing the cap nut from the end of the hollow handle and forcing grease in through the handle with a handgun loader (fig. 12-4, view A) or a bucket type of lubricant pump (fig. 12-4, view B).
The handgun loader is a 25-pound container equipped with a hand-operated pump and a fitting that mates with the opening in the handle of the grease gun. The bucket type of lubricant pump makes use of loader
Figure 12-3.-Hand-operated grease guns.
adapter and loader valve when it is used for loading a grease gun. One pound of lubricant is delivered with every seven full strokes of the pump. The loader will deliver lubricant only when the grease gun is placed on the loader valve. The job is much less messy with the loader, and it protects the lubricant against contamination. Besides, you do not have to run back to the storeroom to refill your gun.
Different nozzles can be attached to the grease gun for different types of fittings. The lubricant pump has various couplers and adapters that attach to the hose, allowing the pump to be used on different fittings.
A grease gun can be used for oil if the point to be lubricated has the proper fittings, or an oil gun (fig. 12-3, view E) maybe used.
A lever type of grease gun (fig. 12-3, views C and D) is being introduced; it gives more positive lubrication than the push type (Zerk) of grease gun.
When you need to apply large quantities of grease-as, for example, in a gun mount roller path-a grease gun is too small. The bucket type of hand-operated lubricant pump (fig. 12-4, view B) holds the same amount of grease as the handgun loader and is fitted with a pump operated with a lever. It has a 10-foot hose with a hydraulic T-handle adapter and a 90-degree adapter for working in cramped spaces. With this pump you can build up a lubricant pressure of 3,500 psi and deliver a pound of lubricant every 20 full strokes.
The hand-operated lubricant pump can handle any type of lubricant generally required on naval ordnance equipment except greases of the calcium soap type.
If you can arrange it, use several grease guns-one for each type of lubricant you will need. You can save time by taking care of all the fittings requiring a specific type of lubricant before going on to apply the next type. For example, if you are working on a 5"/54 mount, take care of all the fittings around the gunhouse that require MIL-G-81322 before working on those that take MIL-L-18486. After you have finished with the gun, rammer, hoist upper end, and soon, repeat the sequence of application down in the handling room.
Grease fittings are of several types- hydraulic (unofficially called the Zerk fitting, after
Figure 12-4.-Hand-operated grease pumps: A. Handgun loader; B. Bucket type of lubricant pump.
its inventor), button-head, pin-head, and flush (fig. 12-5)0
The hydraulic fitting protrudes from the surface into which it is screwed and has a specially shaped rounded end that the mating nozzle can grip. A spring-loaded ball acts as a check valve. The nozzle will not slip off the fitting during lubrication but can be easily disengaged by a quick forward-backward movement. Figure 12-5, view A, shows a cross-sectional view of a straight hydraulic fitting, and view C shows hydraulic fittings made for different angles. They are made to fit almost any angle and have different threads and body lengths. When using a gun equipped with a nozzle for hydraulic type of fittings, just place the nozzle on the fitting and push forward on the handle. This slips the nozzle onto the fitting and, at the same time, builds up hydraulic pressure in the gun, forcing the grease out of the nozzle. Then relax the pressure. A spring forces the handle back, ready for the next stroke. Three strokes are usually enough. Only one hand is needed to work this type of gun. The grip action of the nozzle coupler holds the nozzle firmly to the fitting until it is pulled free. Hydraulic fittings are being replaced by commercial button-head and pin-head fittings (fig. 12-5, views D
Figure 12-5.-Lubrication fittings.
and E) that provide more positive connection with the grease gun. The grease gun can be used with the button-head fitting by adding an adapter.
The flush fitting (fig. 12-5, view B) is flush with (or below) the surface into which it is set so that it will not foul moving parts. It is also used where there is not sufficient clearance to install protruding fittings. The flush fitting also has a ball type of check valve. When pumping lubricant using a gun equipped for the flush type of fittings, you must exert a steady pressure against the grease-gun nozzle to keep it in contact with the flush fitting, since the nozzle has no grip on the fitting. Otherwise, the method of use is much the same as with hydraulic fittings.
The oil cup with the ball valve (fig. 12-5, view F) is the most popular type for oil fittings.
As with other routine jobs, it helps to have a standard operating procedure that you can follow. Here is one that will be helpful:
1. First, consult the lubrication chart and locate the fitting.
2. Clean the fitting carefully with a lint-free cloth.
3. Apply the correct amount of the specified lubricant. (Be careful of the amount you apply-too much will cause excessive heat in the bearing and strain the grease retainers, while too little is on a par with too late.)
4. Wipe all excess grease from around the fitting.
5. Check off the fitting on your chart. A fitting must not be missed just because it is battered or frozen. A frozen fitting could mean that the lubricant holes throughout the bearing are clogged. This means tearing down the bearing and cleaning all parts carefully. Grease that fitting even if it requires an hour of extra work. This is where a little extra tenacity can pay big dividends later by preventing a major casualty. Plastic protective caps are often provided for fittings. These caps keep out contaminants and also aid in keeping the grease in the fitting.