Empire Tramway (Nevada Historical Society Quarterly, Summer 1973)

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The Empire tramway was used to move ore from the open pit to the mill at Empire.

The Empire Tramway was documented in the Nevada Historical Society Quarterly, Summer 1973," pp. 152-154 by The Black Rock Trailblazers of Gerlach High School.

The document is reproduced below:

The Black Rock Trailblazers of Gerlach High School seem to be living up to predictions that they would be one of the more ambitious Junior History Clubs in the state. At present club members are working on plans for their own museum, have spring field trips planned to Soldiers Meadows, Leadville, and Seven Troughs, and are working on several other projects. Space here, however, shall be devoted to presenting the results of the Black Rock Trailblazers' first major research project, the compilation of information on the Empire tramway. The following article has been edited for publication with only minor corrections in the spelling and structure being made; in all other respects the article represents the work of club members.

Officers of the club are: Donald Lawver, president; Louis Houlet, vice- president; Fleeda West, historian. The club is sponsored by Jim Chirst- man and his wife, Charlene.

The Empire Tramway

Just outside the present town of Empire, in northern Washoe County, lies the remains of one of the greatest engineering feats of the twentieth century. Pacific Portland Cement's 5.2 mile tramway is a monument to man's ingenuity. The tramway was originally built for use in New Empire (near Carson City) by the Pacific Portland Cement Company. However, due to the exhaustion of ore deposits, the New Empire operation was closed and the tramway system moved to Empire to be used in transporting gypsum rock from the quarry to the mill.

During 1923, construction of the tramway was completed extending the system some 5.2 miles southeast of the present United States Gypsum, Empire plant, to the quarry site. The elevation difference over this distance from quarry to mill, is 1,300 feet. Mules were used to transport supplies to construction workers, the majority of whom were Chinese. Transportation of building materials was difficult due to the extreme altitude changes occurring over the route of the tramway.

The tramway consisted of two cables, the first being the track cable which was made of lock coil cable 1 3/8 to 1 1/2 inches in diameter; the second was the traction cable (or traction rope) which was 3/4 inch in diameter. Due to this type of construction, the tramway was referred to as a bi-cable aerial tramway.

The cables were supported by fifty-seven towers constructed of kiln- dried, structural grade, long leaf, yellow pine and Douglas fir. The highest of these towers was tower "E," 1,300 feet above the mill location.

Buckets were loaded at the upper quarry terminal by use of a bin with hydraulically controlled gates. At this terminal, a workman loaded the buckets from the bin. He had two or three buckets in reserve so that he was not rushed with the loading process. Once loaded, the bucket was pushed to the end of the terminal where it was held by a timing gear until one of the previously filled buckets cleared tower "E." This was necessary to prevent surging, meaning the pushing or pulling of the entire tramline. Such pulsation of the line could cause damage to the cable and the towers.

Located in the upper quarry terminal were two electric motors, a fifty horsepower motor to turn the traction cable, and a thirty horsepower motor in reserve. These motors were primarily used as braking devices or speed controls rather than for propelling the line.

Attachment and release of the buckets occurred approximately every fifty-seven seconds. Each bucket traveled on two wheels which rode on the track cable. Attached to these wheels by means of hangers (metal supports) were the buckets, each of which had a capacity of 1,800 pounds. Located in the hanger framework were spring loaded grips which attached the buckets to the traction cable. The grips were automatically engaged and disengaged at the two terminals. There were 217 buckets of this capacity on the tramline during peak production periods. When it became necessary to decrease the number of buckets, the number had to be lowered to the next prescribed combination. The different combinations were necessary to prevent surging due to the uneven spacing of the buckets. For example, the next combination under 217 was 186. It was possible to run the tramline with four of five buckets missing, but if the number missing was greater than five, it was necessary to use the next lower combination.

The tramway was operated by one mechanic, four operators, and a tramrider during each shift. When there was trouble on the tramway the mechanic would be dispatched to fix it; if the problem was too serious for a lone mechanic, others were sent to assist with repairs. When serious problems occurred, the tramway generally had to be shut down for the time it took to make repairs.

Four operators were needed to control the tramline. These men were the guardians of the tramline. It was their job to make sure that the buckets entered and exited the terminals at the correct speed. They were able to determine by the sound of the electric motors if the buckets had wrecked at any point along the tramline. This ability to detect problems by the sound of the motors took years of experience to develop.

As indicated, the electric motors acted mainly as brakes or controls. When a power failure occurred, the gravity pull of the loaded buckets would cause a runaway. To stop the runaway, the operator would engage hand brakes on the Bull Wheel, which was the giant pulley on each end of the traction cable. This was done by screwing the brakes down on the surface of the Bull Wheel. If these brakes were not engaged immediately the buckets would smash towers, or would leave the overhead track at the terminals and demolish the buildings. Sometimes the buckets would lose their grip and roll back to the next bucket. When this happened, the operator would have to stop the tramline before the bucket behind pushed the first bucket over one of the high towers. If the loose bucket was allowed to go over the tower, it would rush out of control into the bucket ahead of it. This would generally cause the second bucket to lose its grip and roll into the next bucket on the line. By means of this chain reaction, several buckets might become disengaged. Such a chain reaction would only stop when the lead bucket crashed into one of the towers or the terminal. When this happened, the tramline would have to be shut down to repair the damaged tower or building.

Within each tower there were a number of pulleys or rollers which supported the traction cable and the track cable. It was necessary to grease these pulleys frequently; this was the job of the tramrider. To move from one tower to another, it was necessary for the tramrider to ride down the tramline in a loaded bucket and return in an empty one. The tramrider would step into a loaded bucket and ride to the first tower. Once at the tower he would step from the bucket to the tower, and grease the rollers and pulleys. When this job was completed, he would step into another bucket and ride to the next tower to repeat the operation. This procedure was continued until the entire tramline, or fifty-seven towers were greased.

it was during this procedure of greasing the towers that a bucket fell from the track cable with the tramrider inside. This accident happened at one of the highest points of the tramline, some t450- feet above the ground. When the tramrider did not arrive at the lower terminal in a reasonable amount of time, men were sent to search for him. They found the tramrider's body in a ravine with the bucket.

Another death occurred on the tramway during a cable splicing operation. In order to splice the larger track cable it was necessary to pull some slack in the cable. This was done with a block and tackle arrangement pulled by a tractor. During the pulling up of slack, the cable broke and wrapped around a workman's body, nearly cutting him in half.

According to available information, these are the only two fatalities which which occurred on the tramline during its entire operation.

In later years, the towers became brittle and unable to stand the stress of operation. when the wooden towers were damaged, it because necessary to replace them with steel towers. They steel towers proved extremely expensive to construct. Due to the increased cost of maintenance and operation of the tramline, alternative methods of transporting the rock from the quarry to the mill were researched.

The tramline made its last run in December of 1964. At this time it was decided that the tramway would not be reopened. In August 1965, truck haulage began replacing the tramway operation.

References