Outside the wind was getting stronger and even the half-hearted attempts to rain had left the hard red clay of the location slick and treacherous. The equipment was looking good, its grey and black livery shining in the rain. The cement would soon take the shine away. On the mud tanks Rene and his crew were manhandling drums of chemicals, pouring them into the dirty water and carefully turning it into the exact solution they would need to prepare the cement slurry. Casing was being rolled from the racks onto the catwalk, and hoisted up to the rig floor a joint at a time. Suspended up over the hole, one of the casing crew on the stabbing board half way up the derrick held it straight while his companion down below threaded it and made it up tight using the hydraulic power tongs. They should be finished in a couple of hours. Then all that remained would be to circulate the mud for an hour or two to clean up the hole, and the cement job could start.
It was late afternoon when the cement head was sent up to the floor. Terry had made good his promise of spacing out correctly, and the top of the casing protruded only a couple of feet above the slips. The massive grey cement head held the two large rubber tampons that would be pumped ahead and behind the cement, physically separating it from the mud in the casing. The rig crew had made themselves scarce and Terry was forced to operate the air-winch to bring it up to the floor. He inched the head over the casing and the MacAllans crew carefully made up the threads and hammered it tight.
Then the high pressure line from the pump trucks had to be brought up. The heavy-walled joints of pipe with their Chiksan swivels and hammer unions were laid across the floor to the cement head like a disjointed snake. As soon as pumping started it would be vibrating fiercely, and the Chiksans gave the flexibility that would stop it shaking itself to pieces. They put a tee in the line to allow the rig pumps to be connected into the system. If anything went wrong with the pump trucks, the rig could take over and displace whatever cement was in the casing before it was too late. The last thing to do was to thread a steel safety cable through eyes on the pipe. A failure under pressure could see the heavy joints of pipe whipping around like grass in the wind and the cable would at least restrict it.
MacAllans were very tough on safety, and every job had to start with a meeting. Rene called the crew over to the shelter of the cement silos and waited for Terry and the rig crew to join them. Darkness was gathering as Terry plodded towards them on the wet catwalk. Alone.
“I couldn’t find the cook. He must be in his pit or something and no-one wants to go get him. So it wasn’t worth bringing the driller because he wouldn’t understand anything without the translator. Right. What’s the plan?”
Rene was the man on this job, so he took the meeting. “First off, I’ve got to test the lines. 2500, 3000 psi for five minutes. That should be enough for a job like this. Then there’s a hundred barrels of water and a hundred barrels of wash, and we can drop the plug. The bottom plug.”
“You sure that’s the bottom plug, Rene?” asked Terry, only half joking.
“You bet. Put them in myself. OK. Then we start mixing the lead cement. I’ve got it in this silo, in that one there, and over here. We’ll be blowing it across during the job. Save us having to run the hopper around. Until we get to the tail anyway. That’s in this tank and we’ll move the hopper across for it.”
“What are the quantities?” asked Terry, opening his tally book.
“I’ve got 883 barrels of lead at 10 pounds per gallon. Then 55 barrels of tail at 15.8 pounds per gallon. And 886 barrels of displacement.”
“886 of displacement. Right. You using both trucks to displace?”
“Well, I’ll try to go at 12 barrels a minute, so I’ll probably need both to get it down the two inch line. Oh, about the weight. This 10 pound lead is real critical. I only have to be a point or two pounds per gallon up or down, and we’ll run out of cement or water before we’ve mixed enough. So I’m not listening to any yo-yo with a regular mud balance telling me I’m wrong. I’m taking the weight off the densitometer panel. Greg’ll check it with the pressurised mud balance so you’ll have some kind of second opinion.”
Terry smiled, knowing that control of slurry weight was what made for a good cement job. “Sounds fine. I don’t expect the mud-man will be available to give you a hard time anyway. Just make sure you keep me some surface samples, that’s all. What else?”
The Virgin took the floor. “About the timing. We’ve got 938 barrels to mix. Say we go at 8 barrels a minute, that’s 120 minutes plus a bit for stopping and starting when we go onto the tail. And then dropping the top plug - say two and a half hours. The thickening time on the lead cement is only five hours twenty minutes so we’ve got two hours and fifty minutes to displace. Maximum, no allowances. We better plan on getting it away in two hours, so that’s just about seven and a half barrels a minute. If we’re not displacing at that rate, we’d better expect to have it setting up on us before we’ve finished displacing.”
“OK, OK. I hear you. If the mud’s not coming across at that rate or better, or if one of the trucks goes down or something, we’ll switch over to the mud pumps. I’ll have them all standing by. Promise. What else?”
Rene took over again. “Er - the usual. Fire extinguishers are all around - you can see them. The eye-wash station is the back of my pick-up over there. We’d better make sure we’re all wearing our safety gear because Greg’s here and he’ll be writing an audit report, I’m sure. And that’s about it. Greg, you going to get on the floor for the pressure test and dropping the plug? Can we trust you to do that?”
“If you’ve loaded it right, I’ll drop it right.”
“Good. So let’s move.” After a last look around, he climbed up onto the nearest truck. He flicked on the working lights and stood above them like an orchestral conductor. Leaning on the air starts he fired up both engines and the job officially began.
The Virgin took a valve bar and made his way along the catwalk and up to the rig floor. It was deserted. The big grey cement head stood glistening in the rain. He checked that the lower circulating valve was open and walked to the railing. Rene and Edgar stood on the truck, looking up at him. He joined his hands together and held his arms over his head making a big open circle, the signal that the valve was open and pumping could start. He saw Rene concentrate on his panel controls and the deck engine of the pump truck raised its exhaust flapper and belched smoke. The pipe beside him started to pulse as Rene pumped water into the hole.
After a few barrels, he stopped and held his arms crossed over his head. The Virgin went over to the cement head and slipping his valve bar into the control wheel, swung on the circulating valve to pull it closed. From the railing he sent a confirmatory crossed arms signal. Again the deck engine lifted its exhaust flap as Rene slowly pressured up against the closed valve. The Virgin retreated behind the drill-pipe standing in the derrick. If a union or a swivel was going to blow, this would be when it happened. The pumping stopped and Rene and Edgar were standing close together staring at the DAC display, looking for signs of a leak. Sheltered from the wind by the drill-pipe, The Virgin watched drizzle slanting through the derrick lights. There was a light clunk as Rene bled off pressure and the Chiksans relaxed. He was signalling for the valve to be opened again.
Pumping the fresh water and the wash took twenty minutes, so The Virgin took himself off to the dog house. Inside the driller sat smoking in front of an electric fire that glowed cherry-red. He waved The Virgin to a seat beside him and offered him a smoke. They sat together in silence until the vibration of the line stopped and told them that the wash had been pumped. The Virgin hurried to the railing. Rene was holding his nose and pulling an imaginary lavatory chain. It was time to drop the bottom plug. The Virgin stood on the casing slips and turned the wheel. As the 25 millimetre thick rod pulled back, he heard the retaining spade drop inside the head. The plug was now free to be pumped down into the well. He closed the circulating valve and routed the flow through the centre port above the plug.
Everything was nearly ready at the trucks. Rene had transferred onto the mixing truck; he would control the critical part of the job himself. Edgar would pump down-hole with the other unit. Felix was giving the equipment a last-minute spray with diesel. Cement dust would stick to it but it would not set hard the way it would with water. It made washing up so much easier. Bjorn the trainee had been given the easiest and dirtiest job, controlling the flow of dry cement into the mixing hopper. He was in full safety gear. Hard hat, goggles, dust-mask and ear defenders. It made him look like a refugee from Paschendaele. They all stood looking at Rene, under starter’s orders and waiting for the off.
Rene, the respected actor alone on his raised stage, was making last minute adjustments to the DAC. Then almost casually he walked back to the mixing manifold and hauled open the master valve. At the control panel he fired up both engines and the hopper began to throb as the hidden jets roared with mix-water. He brought his arm down and Bjorn swung on the twelve-inch valve at the bottom of the silo. For an instant nothing happened then the dry cement crashed down, filling the hopper and avalanching over the sides. Dust was everywhere and Bjorn was struggling to get the valve closed again, to achieve some kind of balance between supply and demand. The mix-water gushing into the tub changed into liquid cement. Rene watched carefully, making sure of an even flow while he stabilised his weight. It took seconds. He was holding his thumb up to them while fine-tuning the weight with his other hand on the by-pass valve.
From behind the dust cloud Edgar fired up his unit to suck from the tub and pump down-hole. For an instant The Virgin’s heart leapt; Edgar would not be able to see the tub through the dust. The thought had hardly come to him when the wind cleared the dust away. Rene had rigged it up that way, the wind blowing from the trucks across the hopper, keeping everything clear.
On the mixing truck Rene had no need of goggles or dust mask; he was above it all. He smiled at The Virgin and kissed his fingertips. Everything was going to be alright.
There was little for The Virgin to do during the job. Terry tried to take him off for a coffee, but his conscience would not let him go while the job was on. He felt like an old-fashioned officer. If the men were getting wet then, dammit, so would he. He ran a couple of weight checks with the pressurised mud balance. Spot on. He filled two tin cans from the kitchen with cement for Terry’s surface samples and left them out of the rain under the catwalk. Apart from that, there was the service quality audit to be done. He wondered around the equipment making notes, counting fire-extinguishers and examining their service tags. They were all up to date. An old hand like Rene would not be caught out by details.
The warmth and comfort of his car beckoned but he fought against it and climbed up to join Rene. After the day’s rain everywhere was muddy, and the way up to the operator’s deck of the pump truck had to be negotiated with care. His route took him past the deck engine, screaming away at its optimum 2000 rpm. It was covered with tempting handholds but you did not have to be long around pump units to learn that they were all burning hot.
On deck, Rene was standing at the panel, his belly protruding over it, hands ready to throttle back at an instant. When he felt the deck grating move under The Virgin’s weight he looked up and smiled. Conversation was impossible with both engines running so he returned to his panel. As time went on, pump unit control panels were becoming more and more complicated. This one looked like something from a small plane. There were monitoring dials and lights for the vital functions of both engines and their transmissions, temperatures, oil pressures, revs. And the auxiliary equipment, the hydraulic and air systems that kept things running together. The great pumps needed oil pressure readings; the make-up and pressurising centrifugals needed hydraulic pressures. The two sides of the panel were dominated by the throttle and shift control for each engine, and the two vital dials for each pump, rate and pressure.
On his left, mounted separately over the mixing manifold, hung the densitometer panel, displaying a radioactive density reading. It was steady on ten pounds a gallon, occasionally flicking up or down a point just to show it was alive. To the right of the panel on a heavy bracket was the DAC, the data acquisition computer. It was recording rates, pressures and fluid densities from both trucks. The total pumped showed 425 barrels and climbing. They were not yet half way through the mixing.
Behind Rene, Manny was working the twin displacement tanks. He was filling one ten-barrel tank while Rene was pumping from the other. Every couple of minutes, as a tank was drawn down to the zero marker, he would switch valves and start the new tank. At each change, he slid a washer from one side of a miniature croquet hoop to the other. It was a primitive but effective totaliser. He knew exactly how much mixwater had been pumped and if the DAC had gone down, they could still finish the job accurately.
The Virgin settled himself down on the DAC transport box, wedged into a corner between the deck engine and the displacement tanks. It was windy up here, but at least the engine gave some warmth. He settled his ear defenders more comfortably and lost himself in his thoughts.
He was brought to by the engines throttling down abruptly. It was time to switch to the tail cement. Felix, Bjorn and Joe Milut were wrestling to get the hopper off. They threw it to one side and man-handled the mixing bowl with the goose-neck and heavy hoses still attached around the silo legs until it was under the right silo. Bjorn wanted to put the hopper back on, but Rene was shouting and waving him away. Felix knew what he wanted and unwound the diesel spray hose from its cleats at the rear of the truck. Rene wanted the cement to drop through the hopper without sticking to the sides, so Felix sprayed the insides with diesel. Attention to detail.
They were standing again waiting for Rene. Pausing to send a quick signal to the DAC, he opened the mixing manifold and fired up the engines. Again he brought his arm down down and Bjorn swung on his valve handle. The Virgin watched as the densitometer readings climbed from water at 8.32 pounds per gallon up to 15 pounds. Then slowly up to 15.8 pounds per gallon, the norm for Class G cement. They were in business again. He tapped Rene on the shoulder and set off for the rig floor. It would soon be time to drop the top plug.
Joe Milut hurried up the cat-walk ahead of him. He would warn the rig to start delivering mud for displacement. Joe could talk to anyone, even Romanians. The floor was still deserted. Looking back beyond the end of the cat-walk, the MacAllans’ equipment was a small island of activity. Blowing cement dust blurred the outlines and trapped the light around the trucks. The pipe across the floor pulsed with the beat of the pumps and everything on the rig rattled in sympathy. Even the stands of drill-pipe towering above him were swaying to the music. He waited at the railing for Rene’s signal to drop the top plug. It came soon enough and he backed out the pin and switched valves again.
Edgar was not watching for his signal. He was hanging over his displacement tanks waiting for the mud to arrive. It surged into the tank, a silver fan in the lights. A few moments and they would be ready to go. The pipe started to vibrate as Edgar brought his pumps on line. Displacement had started. All they had to do was pump the top plug all the way down the casing before the cement started to set.
When The Virgin reached the units he could see there was a problem. Rene had switched trucks and was standing with Edgar. They were staring at the displacement tanks and timing the inflow. The Virgin clambered up to join him. The DAC showed they were pumping at 4.5 barrels a minute. He lifted one side of his ear defenders to let Rene shout in carefully articulated words, “Get more mud quickly, OK? Or the rig will have to displace.”
“Keep pumping!” was all he could reply before running off to find Terry.
Terry had been watching from his window and met him half-way. “What’s up?”
“You’ve guessed. They’re only giving us four and a half barrels a minute.”
“Oh fuck! What do you want?”
“Either get them moving or we’ll have to go to Plan B.”
“Shit - I hope it
don’t come to that. They don’t have stroke counters or nothing. Hang around, I’ll get the cook and the tool pusher.”
The Virgin took a moment to steal a quick coffee from Terry’s percolator. It tasted good. He was still sipping when Terry came back from the camp with the stocky figure of the tool-pusher and the cook still in his apron. The four of them hurried to the back of the rig, round the motors to the mud pressurising system. The tool pusher had a quick conference with two relaxed hands smoking at the door of the motor man’s shack, and relayed the results to the cook.
The cook passed them on to Terry. “He say they not pump any more.”
“Why the hell not? They’re only doing four and a half barrels a minute.”
The tool pusher was explaining something to the cook with gestures that meant nothing to Terry and apparently very little to the cook. “He say they must pump backwards to do this and so they not pump any more.”
“Pump backwards? What the fuck’s he talking about? Backwards? Have him show me!”
They clambered over pallets and old sacks towards the mud system pressurising pumps. The tool pusher pointed out the line leading forwards to the pump unit and showed where it was flanged into the yellow manifold. It came from a tee on an eight inch line. The Virgin and Terry stared at it for a moment. Something looked wrong and it was Terry that picked it up first.
“Holy shit! That’s on the suction side!”
The tool pusher was showing the valve between the eight inch line and the neighbouring tank. It was closed. Then with his hand he showed the route the mud was taking. It was being sucked out of the next tank by one big centrifugal and delivered to a shared manifold. The off-take from the manifold was closed so the mud carried on to the neighbouring centrifugal. This one was switched off because the mud was being forced back through it to the suction side and so out to the delivery line.
The Accidental Spy Page 15