“Admiralty Oil-fuel Pipe-line from the Clyde to the Firth”.
1. Introduction.
The construction of an oil-fuel pipe-line from the River Clyde to the Firth of Forth was sanctioned by the Board of Admiralty on March 7, 1918. The decision to carry out this work was the result of the urgent necessity for utilising oil-fuel tankers to the utmost advantage by reducing the time occupied on voyages to a minimum, and of the need to avoid the increased risk of losses by submarine attack during the passage through the North Sea to the Firth of Forth. The object in view was to convey oil, from tankers in the River Clyde, across Scotland to the receiving tanks at Grangemouth – which are used for filling oilers for the supply of oil-fuel to H.M. Ships in the Firth of forth – and to deliver any surplus to Rosyth.
The construction of an oil pipe-line of the magnitude involved was a novelty in this country. Notwithstanding the difficulties resulting from war conditions, the work was carried out, however, in a comparatively short time, oil being pumped into one of the Grangemouth tanks on November 9, 1918. The scheme was prepared by the Staff of the Civil Engineer-in-Chief of the Admiralty in February 1918, after consultation with the Admiralty Departments concerned, and under the advice of Mr Forrest M. Towl, who is an authority on oil pipe-line work in the United States of America.
2. Route and Pumping Stations.
The route chosen is for the greater part along the old Forth and Clyde Barge Canal. The pipe-line commences at the Admiralty Clyde Oil-fuel Installation at Old Kilpatrick, and is laid along the towpath of the canal to the oil tanks at Grangemouth, a distance of approximately 36 miles. The oil is transferred from these tanks to Rosyth main installation by means of R.F.A. Oilers.
The pipe-line itself is divided into three sections, each approximately 12 miles long. There are three main pumping stations; the first is at the Clyde Receiving Station at Old Kilpatrick, and intermediate stations are provided at Hungryside and Castlecary. In addition there is a small set of pumps installed at the Caledonian Railway Company’s Dock pumping station at Grangemouth, used only for filling oilers. The terminal stations are situated a little above high-water level, while those at Hungryside and Castlecary are about 150 feet above sea-level. Each main pumping station is provided with duplicate pumps and 50 per cent. spare boiler capacity. Each pump is estimated to deliver oil having a viscosity of 175 seconds on a Redwood No. 1 viscometer, at the rate of 100 tons per hour at a pressure of 250lb per sq. in. Heaters are provided by means of which the oil can be warmed to a maximum temperature of 150 degrees F., to reduce the viscosity to the value required. The velocity of the oil through the pipe-line, when pumping, is about 3 feet per second. Further particulars of the equipment are given in Art. II.
3. Details of Pipes.
As oil pipe-line work involving long-distance transmission was a novelty in this country, the pipes were made, and the pipe-line working party was recruited, in the United States, this working party being a United States naval Unit. The pipes are of steel, lap-welded, 8in. in diameter, 3/8 in. thick, and about 20ft 6in. long, with screwed-on sockets on one end of each pipe. The American Standard Taper Thread was used. The pipe were tested at the works to a pressure of 1,200lb per sq. in. The thread on the free ends was protected with steel coverings during shipment and transit. The pipes, which were made in about 10 days from the date the makers received instructions, were shipped to Manchester, arriving there on July 1, 1918; they were delivered by rail to Glasgow and Grangemouth, and despatched thence by barge and lorry along the canal. [Most were taken by the lighters Vulcan (33t), Trojan (36t) and Briton IV (39t) between 4th July and 10th July 1918, and only the last consignment was conveyed by lorry on 13th July.] In all, about 9,500 pipes were shipped from America, weighing approximately 3,000 tons, and these were distributed along the canal and for the most part strung out ready for laying within a fortnight of their arrival in England. Pipe-laying commenced on July 11.
4. Supervision and Jointing.
The American pipe-line working party consisted of 112 men. This unit was divided into two sections, with separate camps about six miles apart, each section jointing a length of pipe-line extending three miles on either side of the respective camps. The United States working party was concerned mainly with the jointing of the pipes, the trenching and lowering being carried out partly by a local contractor and partly by two companies of Royal Marine Engineers. The lowering of the pipes into the trench was, however, supervised by the mechanics attached to the United States working party. The first section to be taken in hand was between Old Kilpatrick and Hungryside. The pipe was laid in the first place on the surface of the ground, or in some cases on supports over a trench, and the whole six-mile section was finally laid in the trench in one continuous length. The operation of jointing consisted of stabbing the spigot end of the pipe into the screw socket of the last pipe laid. After the pipe was properly stabbed, the pipe was turned by ropes until the thread was moderately tight. The tongs were then brought into use, two sets only being used at first and finishing up with four. While the pipe was being screwed in, continual hammering was kept up on the socket, which not only helped to ensure the tightness of the joint but was used as a means of getting the men to work in unison and to signal instructions for the various operations. There was keen competition between the two sections of the working party to register the “record” for the number of pipes jointed per day. The “record” number of pipes laid in one day by one section was 215, equivalent to 1,400 lineal yards. The maximum combined day’s work for the two parties was 357 pipes, equivalent to 1.4 miles and the average day’s work over the 2.5 months from July 11 to September 29 occupied inlaying was 0.6 mile.
5. Bending.
There are 1,040 bends in the pipe line. Practically all of these were made on the site and, unless the position was confined and the length short, the pipes were bent cold. A bend was made by jointing up several pipes, supporting the pipe at the bend-point, and using the weight of a crowd of men standing on the pipes on either side for bending. When a horizontal bend was required, a vertical bend was made in the first instance. The bent pipe was then screwed round a little further into the collar of the adjoining pipe, by which means the bend was brought from the vertical to the horizontal or even turned completely round when an upward bend was required. Hot bends were avoided unless absolutely necessary. The junctions between the six-mile sections were made by screwing flanges on to the two end pipes and bolting together.
6. Laying
pipes in trenches. As mentioned above, the jointing of the pipe-line was done on the surface, thus facilitating the use of tongs. The trench was dug alongside as quickly as possible after the pipes were jointed, thus providing for slight errors of alignment due to the cold bending. In excavating the trench care was taken that the line of the pipe “wandered” from side to side of the trench in order that there should be plenty of slack for contraction. It was also necessary to ensure that at side-bends and over-bends the pipe was not bound. Ample freedom is necessary as there may be variation in temperature of as much as 100 degrees F. in a hot-oil pipe-line. In the case of road crossings, railways, & c, it is not possible to lay the pipes on the surface before lowering. Generally in such cases special cover-pipes were placed in advance below the roadway or track and approach trenches were dug. The necessary pipes were then jointed together and pushed through the cover-pipes. The pipes were lowered into the trenches continuously by means of sheer legs or “horses”, starting at one end and working forward towards the other end of the trench. The pipe was laid throughout without expansion joints, air valves, or stop valves. A free moving line without any local stiffness was aimed at. Flanges would have interfered with this, and are considered a source of weakness.
7. Grangemouth Canal Crossing.
In places the canal path is very narrow and was already occupied by a large number of existing mains. There were, in addition, a number of obstructions to be passed over and crossings to be provided, some of which presented points of difficulty. Of these, mention may be made of the crossing of the canal near Grangemouth. In the earlier part of the summer of 1918 there was a serious shortage of water in the canal and the engineers responsible for the navigation were anxious to prevent any loss which could be avoided. It was decided in consequence to tunnel under the canal, but unfortunately in the course of this operation the water broke through. The reach of the canal where the crossing of the pipe-line occurs was therefore drained, a trench excavated, and a cover-pipe provided below the bed of the canal. A start was made with draining the reach at 7pm on September 13 and the canal was made good and water readmitted to the reach on September 17. After the approach trenches on either side of the canal had been executed, the pipe-line was stabbed through the cover-pipes.
8. Camp Accommodation.
It has already been mentioned that the United States pipe-line working party was divided into two groups, each occupying separate camps about 6 miles apart. When the party had completed one section of 12 miles it was moved on to the next section. In this way each camp was moved three times in the course of the work. Camp sites had to be chosen, and store barges and launches had to be hired, one for each party. Arrangements were also made to connect the camps by telephone with the Admiralty Civil Engineer in charge of the work. The two companies of Royal Marine Engineers were quartered in barges in which temporary housing accommodation had been built. The barges were moved along the canal as required. The United States personnel were camped under canvas. The United States pipe-line party broke up at the end of September 1918, most of them going to France, but 25 mechanics stayed behind until the line was in thorough working order.
9. Completion of Pipe-Line.
The pumps were ready for use on October 31. On November 1, oil was pumped from the Clyde to Hungryside tank; and on November 5, oil was delivered into the Castlecary tank. On November 9, oil was pumped into the Grangemouth tank, and by the following week the whole line was in full and satisfactory working order.
10. Progress of Pumping Stations.
Under war conditions, the construction of three pumping stations, involving extensive foundations for machinery and the erection of boiler batteries, pumps, balancing tanks, heaters and station pipework, in the limited time available, was a matter which called for considerable foresight. The most important part of this section of the work was at Old Kilpatrick, where access to the site was not obtained until early in April 1918, and where an extensive Oil Fuel Storage Installation was being provided by the Admiralty simultaneously with the construction of the pipe-line. The plant for this work was difficult to obtain, but, notwithstanding the adverse conditions, a deep berth for oilers in the River Clyde, with temporary wharfage, was in use before the end of October, and two 8,000-ton tanks were completed and full of oil before November 1, 1918. At this date ten other tanks were in various stages of construction, and a large amount of work had been done in preparing foundations, constructing railways, retaining banks, housing, store accommodation, and in laying the pipe line from the tanks and wharf to the pump houses. Similarly at Grangemouth four 8,000-tin tanks with pipe-lines and pumps had been constructed on a site adjoining the existing wharfage. The constructional work at the receiving, terminal, and intermediate stations was carried out by contract.
11. Items of Plant.
The following are the principal items of plant provided at the Old Kilpatrick Pumping Station:
- Four Babcock and Wilcox water-tube boilers, hand fired, each capable of supplying 6,000lb of steam per hour. Working pressure 160lb per square inch. Two boilers can supply steam for one pump.
- At this station there is an extra boiler provided for heating the oil in four tanks of the installation, for issue of oil to H.M. Ships in cold weather.
- Two low speed (about 18 revolutions per minute) Worthington horizontal duplex pumps. The working pressure is 250lb per square inch, and the pumps deliver 100 tons per hour.
- Two heaters of the Pearson Oil Heater type, capable of raising the temperature of the oil to 150 degrees F. are placed on the suction side of the pumps. Each heater is divided into three horizontal sections and the oil passes through a number of 1.25 inch diameter pipes. The pipes are heated by exhaust steam from the pumps. The heaters are designed on lines similar to condensing plant. The exhaust steam, after transmitting its heat to the oil, condenses and is pumped back to supply feed-water to the boilers.
- One distributing oil-receiver with the necessary valves is placed on the suction lines from the storage tanks at Old Kilpatrick.
- The heaters and receiver are placed at a level which ensures them being constantly flooded with oil.
The plant at Castlecary and Hungryside Stations is generally similar to that at Old Kilpatrick, with the exception that there are only three boilers instead of four, and no distributing oil-receiver is provided.
The plant at Grangemouth consists of two small pumps for which steam is supplied by the Caledonian Railway Company. These are used for accelerating the flow from the tanks to the oilers alongside the wharfage.
Falkirk Local History Society 