PLAN No. 1126. REAR AXLES
The building of rear axles is practically an industry in itself. There are several large companies who do nothing else but manufacture gears, and front and rear axles. In this branch of the industry we find all kinds of work going on, including forging, pressed-steel work, machining, heat treatment, and oxy-acetylene welding.
The rear-axle housing may be a casting or it may be pressed steel, or a forging. Where castings are used we have foundry work employing molders, core men, flask men, and cupola men. Most of the jobs in the foundry require men of sturdy build and good physical condition. Some foundry work, however, such as inspection, core work, and testing small castings, can be done sitting. Again there are jobs, such as trimming, grinding, and filing, that can be done by a man with one arm or one leg. The average foundry man is well paid and works short hours, but the work is dirty and not generally well suited for handicapped men.
The pressed-steel department of the rear-axle factory is equipped with special machines for pressing various parts into shape. Some of these machines could be operated by a man with one good leg or one leg and one arm.
In another department of the axle factory, brake supports are assembled. Here men stand at benches, riveting and bolting to the axle, housing the various necessary braces, and other pieces. Some of this work is heavy and some very light.
Gears for the rear axle, some eight in number, have been machined in the machine shop, heat-treated in the heat-treatment department, tested and inspected in the inspection department, and are now ready for the assembly of the differential.
In the machine shop and inspection department much of the work could be done efficiently by handicapped men who have been trained for it. Some of this work requires technical skill, some a technical education, but some of it requires just plain everyday common sense.
The differential housing (two halves) is usually a malleable casting. It is machined in the machine department and inspected in the inspection department.
All of the necessary parts for assembling the differential are brought to the differential assembly department. Here men fit gears, rivet gears to cases, and assemble the differentials. In some places this work is done by the progressive method, one man putting on one piece and another man another piece, while in other places one man assembles the whole differential. In this department, a man with one leg and two good hands could very well do the work. He must be able to use hand tools, and must know how properly to adjust the gears in the case. The operation is quickly learned and does not require a highly trained man.
After the differential is assembled, it passes to the inspector, and if it meets the necessary requirements, it is ready for the rear axle.
The rear-axle housing having been equipped with brake supports, trues rod and brake levers, is ready for the brake bands and shoes. The brakes are lined with an oil and waterproof lining, which is riveted to the bands or shoes. This operation is done in a riveting machine, each rivet being countersunk and headed. Riveting is done by one man who does nothing else but rivet brake lining to the bands or shoes. A handicapped man might do this work.
The lining having been riveted to the bands, they are now ready for assembling on the rear-axle housing. In some factories a whole axle is assembled by two men, while in others using the progressive method, it is assembled by a number of men, each man doing one specific operation.
After the fittings have been applied to the axle housing, it is then ready for the differential assembly, which is the work of one or two men. They must know how to install the bearings properly on the differential and drive-pinion shaft, and must know how to adjust the gears. If the gears are not properly adjusted, they will be noisy and the wear upon them will be considerably increased. It takes practice to do this work efficiently. Men who assemble the rear axle and differential must be able to move about freely, and should have the free use of both hands.
After the axle has been assembled, it is inspected and passed to the testing department. In the testing department, wheels are applied and the axle mounted on a stand for testing. The axle is driven by an electric motor, brakes being applied to provide the equivalent of a load. The tester then notes the noise of the axle, and the contact surfaces of the teeth, and if final adjustments are necessary they are made in this department. The men are rear-axle experts, and understand thoroughly all the adjustments of the rear axle. They must be able to handle the axles and lifting is often times necessary.
The axle after being tested is numbered, tagged, and sent to the storeroom for shipment. In the rear-axle factory, there are many classes of workers which have not been mentioned. Some of these are draftsmen, tool-room helpers, storekeepers, clerks, checkers, timekeepers, janitors, gate keepers, machine hands, truckmen, and mechanics. Much of the work done by these men could be done by men handicapped by loss of hand, leg, eye, or hearing. All of the work pays a good living wage, and working conditions are good.