29: The Duration of Machinery
The quality of construction and the attentiveness of maintenance will largely determine the duration of machinery. A machine can last a very long time if it is well maintained, or can be destroyed in a very short time if it is not.
He cites the durability of watches, which when well made can last for a very long time and be handed down through generations. He mentions some antique watches that had been made in 1660 (nearly two centuries before the writing of this book) and 1798.
He mentions the importance of routine inspection and maintenance, and particularly the record of a specific mine which maintains a staff of engineers who inspect the steam engines daily, as the stoppage of the equipment means the stoppage of production, immediate loss of revenue, and potential loss of clients who depend on the mine for a regular supply.
Random bits: The greater the amount of motion of a part and its friction with other parts or surfaces, the more prone it is to wearing out. The more complicated a machine, the more parts that can wear out, and a defect in one may cause damage to others.
The amount of time it takes for a machine to pay its own costs varies by the amount it produces and the savings it generates. Some repay themselves very quickly, others take more time. As a general estimate he suggests five years.
During a period of rapid development and improvement in machinery, it is more likely that a machine will be replaced not because it has worn out, but because a better machine has come along. It is misguided to attempt to maintain a machine to recover its cost when a newer more productive one would quickly recover the cost of both. To emphasize this he gives an account of a cotton manufacturer who was "driven out of the market" by holding onto an inefficient machine when his competitors switched to more efficient ones and underpriced his operation.
There's a meandering passage that seems to intend to communicate the salvage value of older machinery - whether they are purchased for their parts or used to establish an operation that can be profitable at a smaller scale.
Another mention is made of lending out machines - to take in work for other firms and perform part of their manufacturing process. Many textile companies who perform all the tasks to manufacture cloth continue to sell yarn to those who weave in smaller quantities - and as such can make additional profit from their spinning machines by producing more than is needed for their own operations.
(EN: He natters on for a while, having departed entirely from the topic of this chapter.)
There is a bit that suggests predicting the rate at which some of the parts of a machine may be expected to wear out. Any cutting blade tends to dull and parts that stamp material wear out. It should be feasible to track their need of maintenance according to the output, though some wear faster at higher speeds. Of course, a well-made machine will be constructed to facilitate the replacement of these parts.
Another design feature of a well-made machine is in providing gauges, indicators, and alarms that call attention to problems that arise. A machine that operates with a faulty part will soon need much more serious repair if it continues to operate.
He speaks at some length of the use of springs and pistons, which absorb shock to reduce the stress on machine parts. Careful configuration is necessary to ensure that the machine is rigged to exert the level of force needed for a task, but no more than that as it will unnecessarily wear on the machinery.