en zh es ja ko pt

Volume 17, Number 2March/April 1966

In This Issue

Back to Table of Contents

In the nerve center of Aramco's distribution operations, skilled dispatachers regulate the flow of 85 million gallons of oil every day...

At The Turn Of The Tap

Written by John Ballantine
Photographed by Burnett H. Moody

A chain of circumstance is the only tie that binds together Paul Mayer and Ali Hamed. The one is a bank teller in Hamburg, Germany, father of three, owner of a little brick row house with a vegetable garden in the back; the other is an oil dispatcher in Abqaiq, Saudi Arabia. Though they have never met and never will, they are at opposite ends of a sequence of events set in motion by the considered opinion at the weather station in Hamburg that this March will be slightly cooler than it was last year.

This information, which might provoke a mild yawn from Herr Mayer, elicits quite a different reaction from the petroleum marketing organization in Hamburg which supplies him, among thousands of others, with fuel oil. A quick slide-rule calculation assures the supplier that as a result of the predicted two-degree drop in mean temperature, he will require six per cent more fuel oil than he did the previous March, and immediately he increases his standing order with the nearest refinery. The refiner, who has enough oil on hand to fill the order with ease is, however, a cautious man who prefers to keep his reserves at a safe level. So into the international petroleum market the goes, to find a company which can supply him with additional crude on reasonable terms.

As it happens, the German affiliate of one of the four U.S. petroleum firms which owns the Arabian American Oil Company (Aramco) can offer a favorable combination of price and delivery date. This circumstance resolves the refiner to contract with this owner company for the particular consignment of crude oil from Aramco. The delivery date is as important to him as the price, for he wants the crude at the optimum time—neither so late that he will have to slow down refinery operations while waiting for it, nor so early that he will have to pay heavy storage charges before he can use it.

The same day the contract is signed, a cable revising previous estimates of liftings to include this refiner's order lands on the desk of Supervisor of Dispatchers Subhi M. Sanuri in Abqaiq, Saudi Arabia, the nerve center of Aramco's distribution operations. Meanwhile, the offtaker, the company which takes delivery of Aramco crude oil or products, has gone into the market—the tanker market—to secure the least expensive shipping that can pick up the cargo of oil at the appropriate Middle Eastern point and deliver it to the customer 5,000 miles or so distant on the promised date. Shortly thereafter the ship's master, who may be anywhere on the high seas at that moment, receives a radio message from his home office to proceed to the Saudi Arabian terminal of Ras Tanura, notify Aramco of his estimated time of arrival, load the cargo of crude and depart for northern Europe.

In Abqaiq, well in advance of the ship's estimated time of arrival at Ras Tanura, Supervisor Sanuri has instructed Dispatcher Ali Hamed to order a slight increase in deliveries from wells of Ghawar field to accommodate the incoming ship, which, with such forward planning, will find the crude ready for loading the moment it docks at Ras Tanura. The return journey of the tanker will take the oil by stages to an oil terminal at Cuxhaven on the North Sea, thence to a refinery at Hamburg, the tank truck, and in due course to the home of the unsuspecting, entirely fictitious Paul Mayer, who will not have to return from his banking job to a cold house.

Ali Hamed, on the other hand, is very real, and the fuel-oil saga is in essence typical of what happens whenever a West German citizen, for example, takes an interest in keeping himself and his family warm indoors. With a minimum time spread of a month between order and delivery of overseas crude, a maximum of foresight is required by domestic suppliers in anticipating demands, as is a well-honed efficiency on the part of the oil dispatchers to see that it is filled. Ali Hamed and his seven fellow dispatchers at Abqaiq are the men who supply the delicate touch to the tap that pours forth over 85 million gallons of oil a day.

Watching the dispatcher at work in the control room at Abqaiq, it is impossible to avoid the invidious comparison of his situation with that of the spider in the center of his web. Seated at his desk rimmed by nine telephone sets (four radio circuits, five land lines), hemmed in on the right by an electric calculating machine and on the left by a bank of radio transmitters and receivers connecting him in an emergency with seven separate radio networks, the dispatcher responds to the slightest stimulus from his many invisible filaments, and must react instantly and with mathematical precision. For the movement of petroleum within the network of pipelines that stretches 1,187 miles in all directions from Abqaiq, transporting a substance that is highly volatile, malodorous, explosive, mercurial and precious, the dispatcher has complete responsibility.

To reach this post of trust may take years. Dispatcher-trainees are handpicked from among bright young Aramco employes and put through a rugged program which includes classroom instruction in English, geography, mathematics and allied subjects. There is no "graduation"; a student remains a student until the supervisor of dispatchers is satisfied beyond all doubt that the trainee knows his subject matter backward and forward. The same is true of the ensuing on-the-job training at the various facilities whose activities he will ultimately regulate—the gas-oil separator plants, stabilizers, pump stations, power plants, and so on—where thorough study of the operation, emergency measures and the men who apply them substitutes for a hard-and-fast program.

"After all," observes Supervisor Sanuri, "though the dispatcher has all manner of information on hand to help him—operations manuals, facility limitation statistics, past performance data—in the end 85 per cent of his decisions must be made on the spot under pressure, and must be right the first time; there may not be a second." Conceivably, the trainee's tutelage could last 10 years, but in practice most dispatchers master the details of their work within four years, which is followed by from one to four years at the side of a seasoned dispatcher before they're on their own.

Although its application is a matter of infinite complexity, an art of making a great many small, well-timed decisions, the theory of oil dispatching is fairly simple. To visualize the factors involved it is first necessary to trace the flow of oil from its beginnings at the wellhead to the point where Aramco's customers take charge of it.

The crude oil of eastern Saudi Arabia emerges from about 300 producing wells in 10 different fields and flows under wellhead pressure directly to the nearest gas-oil separator plant. In its natural state crude oil is a liquid containing varying amounts of hydrogen sulfide (the substance which gives rotten eggs their characteristic aroma), natural gas and other impurities. At the highly automated gas-oil separator plants (in the trade, called GOSPs as one word) high-pressure gas is removed and piped out to gas injection facilities, which return it to the underground oil reservoirs to maintain wellhead pressures, thus postponing the day when it will be necessary to pump the wells. Low-pressure gases are separated simultaneously and converted to propane or butane at a liquefied petroleum gas plant, for enriching crude or for direct sale to exporters.

Pumped to the stabilizers, a collection of cylindrical towers and a maze of steel piping, part of the crude's remaining gas is boiled off in reducing the hydrogen sulfide content by about 95 per cent. The stabilized sweetened crude, now safer to handle because its poisonous and corrosive H2 S has been removed, is shunted to tank farms consisting of huge steel storage tanks of 180,000 to 325,000 barrels capacity each, to await final transfer to one of four destinations: the 255,000 barrel-per-day Ras Tanura Refinery; the Ras Tanura Marine Terminal for loading aboard tankers; the pump station in Dhahran which pushes crude oil through twin underwater pipelines to a refinery on the island of Bahrain, 20 miles to the east; and the tank farm at Qaisumah, last stop before a desert journey across northern Saudi Arabia via facilities of the Trans-Arabian Pipe Line Company to its terminal at the ancient Lebanese city of Sidon, on the Mediterranean Sea.

The dispatcher's role in this fairly straightforward process is to keep the oil moving steadily from well to GOSP to pump station to stabilizer to tank farm. In theory all he has to do is to order the valves turned on at the wells until the tank farms are filled, then shut the wells down until the tank farms are empty, before the time comes to repeat the cycle. He could actually do this, except that a sudden descent of empty tankers at Ras Tanura could not be supplied from a near-empty tank farm (nor wait until storage tanks were filled), and, more important, the off-again, on-again operation of such huge facilities is prohibitively expensive. The dispatcher's ideal, indeed, is to keep all his units operating with the minimum possible change, just as the economy-minded driver tries to maintain a moderate but constant speed in traffic, instead of jack-rabbiting from one light to the next.

"Still, with all the equipment operating at peak efficiency," says H. J. Van Hatten, a Nebraska-born mechanical engineer and Aramco pipeline staff man, "dispatching would be a breeze. The bind comes because equipment, being susceptible to wear, corrosion and mechanical failure, must be periodically inspected and repaired, or else risk an accidental and unscheduled stoppage that could put the whole system out of kilter for months. But removing a piece of vital machinery such as a power plant for the days or even weeks it sometimes takes to service it imposes that much extra strain on the other parts of the system to maintain a smooth flow of crude, much as if you were working on one cylinder of an automobile engine while the other five were pulling the car uphill. It also puts a strain on the dispatcher to re-route the crude with as few changes in pressures and rates of flow as possible, and thus avoid ship tie-ups, fluctuations in labor requirements and general administrative headaches."

During a lull on the "slow" afternoon shift, from three o'clock to eleven, Ali Hamed leaned back in his chair, lit a cigarette and pointed to the huge wall flow diagram directly opposite his desk, showing hundreds of valves and eight grades of petroleum and petroleum products represented by thin lines of different colors.

"That," Ali said, "traces the hundreds of miles of pipeline and dozens of facilities controlled from this desk. Every change in pressure or flow rate anywhere must be authorized from here, because what happens at one station affects them all, and only the dispatcher can see everything. He's the only person who has the necessary information to make compensatory adjustments all the way down the line. A lot of work here is routine, meticulous recording of two-hour reports from all the units—GOSP oil temperature, discharge pressure and flow rate, output of sweetened crude from stabilizers and its gravity and H2 S content, weather reports from pipeline stations, and sometimes..."

He leaned forward to answer a radio call that suddenly boomed in.

"Abqaiq One reading," the receiver said above the static.

"Go ahead," Ali answered. He picked up a pencil to jot down the information as it came in.

"Twenty-eight, one zero two, one zero four nine; transfer line; one zero two, three zero four, one nine six two; QA dash two, two five zero..."

As the voice droned on, "Van" van Hatten said:

"This business of 'compensatory adjustments' may be a bit hard to follow the first time 'round. But a few days ago we had a comparatively simple, everyday situation that illustrates what Ali was talking about.

"We wanted to reduce the shipping rate out of Abu Hadriya field to 60 MBCD—that's thousand barrels per calendar day, in order to T and I—that means test and inspect—the Fadhili Gas-Oil Separator Plant which supplies it. Strictly routine. First we reduced the flow out of Abu Hadriya, as scheduled, and shortly afterward shut down the Fadhili GOSP and the wells that flow into it. So far so good.

"However, this field's production goes to the Trans-Arabian pipeline, so in cutting back its flow to 60 MBCD, we were reducing Tap line's intake. To compensate for this loss we increased the flow to QA-3 ("QA" merely denotes one of the pipelines out of Abqaiq leading to Qatif Junction) line, which supplies Tapline. That took care of Tapline's requirements.

Van took a deep breath.

"However,—again—QA-3 also supplements the flow of QA-1 line, which goes to the tank farm at the Ras Tanura Terminal. Now, even when it is operating at full capacity, QA-1 can't supply all that Ras Tanura needs, because up to 10 ships berth every day at its docks. What to do?

"Well, since we knew of the forthcoming T and I a week in advance, we increased the flow out of QA-3 into QA-1 for the 48 hours previous to shutting down the Abu Hadriya GOSP, with the excess-of-normal flow building up a reserve in the Ras Tanura tank farm, to the same degree we had to cut it back once we began to divert part of QA-3's flow from QA-1. See? Had there been any breakdowns, of course, we'd have been in trouble. As it was, it took about 50 hours of switching crude back and forth from on line to another, but the steady flow was never interrupted, and we didn't have to push any of our facilities to the danger point."

He paused to see if all this had sunk in. Apparently reassured, he went on:

"But that, as I say, is a simple situation. A really interesting case, though, came up last..."

At this moment a Teletype machine in the corner began to clatter, and Van lost his audience.

Teletype transmission supplements the dispatcher's radio and telephone circuits for communication within Aramco's pipeline area. In the town where Aramco has its headquarters, Dhahran, a communications center receives messages by radio from Aramco's New York office, ships at sea, and Sidon and Beirut in Lebanon, relaying them by Teletype to Ras Tanura, with information copies to Abqaiq. Many of the cables received are so technical that for the layman they may as well be written in Sanskrit. Others are comparatively comprehensible, as this from a British tanker:


About 10 times a month Aramco's offices in New York send cables to Dhahran similar to the following:



The cable tells the addressees, the General Office Plants and Pipelines Department, Manufacturing Department, the South Pier and the Refiner's Office, that the after the ship referred to by number (R452O) has been loaded, so many thousand barrels of Arabian Light grade crude oil will be required up to the end of the month, so many thousand barrels of Arabian Medium grade and so many of Arabian Heavy. This enables those at Aramco responsible for filling customers' orders to keep up to date on future requirements of Aramco crude oil and products, and is the kind of information that is of vital interest to the oil dispatchers of Abqaiq.

Ali Hamed leaves his desk to sweep his eyes across the twitching Teletype paper, sees nothing urgent, and returns to his desk to finish converting, computing and entering the last of the bihourly readings on his 20- by 56-inch log sheet, now nearly a solid mass of numbers.

"This work is continuous, demanding, and sometimes pretty nerve-racking," he says finally, looking up. "You have to answer automatically in the language which the caller uses—either Arabic or English—and needless to say, you don't want to choose the wrong words. It's been, known to happen that half of these phones start ringing at once. Then you can only answer them one at a time, find out if it's an emergency and, if not, tell the man to stand by until you answer the others."

And what if there is an emergency?

Ali Hamed was thoughtful.

"Then hope that it's a small line break and not a fire. A line break is bad, of course. Sometimes a passing motorist will detect a leak in a pipeline and phone in. Or the 'dispatcher himself will spot a discrepancy from the two-hour readings—notice that there is more being pumped out of one station than is being received at the next. In either case, he sends someone out to check. If the leak is confirmed, he doesn't hesitate, but informs top company officials, orders the upstream pump station to shut down or divert its stream to another line, alerts the repair and maintenance crew, and then becomes the communications link among all concerned. A minor break in the line can usually be repaired in from 10 to 12 hours; a big one takes 16 to 20.

"Fire, of course, is the number one disaster that can strike any oil installation. When fire broke out in the 'Ain Dar GOSP Number One in the spring of 1964, it took only five hours to extinguish and just 72 hours to bring the GOSP back on the line, but the fire caused a $200,000 loss.

"The dispatcher has about five things to do when a fire is spotted, and he usually tries to do all of them first. If it's nighttime he hits that button next to the radio panel and a bell automatically starts ringing in the homes of the fire chief and company executives. He dials 3100 on the emergency phone, which gives him a simultaneous link with the fire chief, supervisor and hospital, so they can get the details at once. He immediately starts to divert the flow of oil around the fire, notifies all stations to be ready for sudden pressure surges as he shuts down sections of the line in the -fire zone. He flips on a tape recorder which, from that moment on, will record every word flowing in and out of the dispatcher's office—and there will be plenty of them, too—and hooks up telephone sets to the radio circuits which blanket every activity concerned with the fire. In less than five minutes the man in charge of each department, the pipeline superintendent, chief engineer, communications supervisor, maintenance superintendent, safety engineer, chief dispatcher, plus the district manager of Abqaiq and his secretary, are gathered here coordinating by radio the work of their men with the fire-fighters. And they won't go home until the fire is out, if they stay here a week. Everybody here knows his job, so no one at the scene of the fire has to wait more than seconds for a decision."

All in all, the dispatcher's job sounds like a 24-hour-a-day proposition.

"Every day. More often it's 25 hours. Sometimes maybe 27."

How's that?

"On top of the dispatcher's regular work, he always has to be thinking about what could go wrong, where potential trouble might pop up suddenly, what could break down in the middle of the night, and then plan for the worst. It's like a chess game in which you always have to think two moves ahead."

Yes, that could easily take an extra hour each day. Leaving two.

"Well, Mr. Sanuri always says that 'the fine art of oil dispatching is always to schedule your breakdowns when your tanks are full and no ships are steaming your way over the horizon.' "


"Those other two hours," Ali smiles, "are what it takes to get yourself out of the mess when you don't."

John Ballantine is a former public relations writer now working in the Middle East as a free lance specialist on technical subjects.

This article appeared on pages 14-21 of the March/April 1966 print edition of Saudi Aramco World.


Check the Public Affairs Digital Image Archive for March/April 1966 images.