What happens when industrial engineers take a look at rig up and rig down.
The scene: from a viewpoint high above a modern factory floor, personnel and parts are observed performing a perfectly choreographed ballet. Parts arrival is precisely synchronized with assembly, which is done by highly efficient workers wasting no motion. Finished products flow to waiting delivery trucks that have arrived just in time to load them.
Cut to a well site on land somewhere. The process of rigging down and moving the rig is under way, but somehow the effect is not the same as our factory scene. Inefficiencies abound, things move slowly and nothing seems to be designed for the purpose.
The factory scene portrays the art of the industrial engineer, whose job is to comb inefficiencies out of manufacturing systems. The script was overdone for dramatic effect; no system is optimum. Human nature being what it is, inefficiencies embed any process, but the industrial engineer can filter a lot of it.
At least they can in any industry that applies them. That's where Chuck Allen and Jim Armstrong enter the scene. They say that the art of industrial engineering can be applied to the tasks of rig up and rig down, with considerable benefit to drilling operations.
"A properly designed rig expertly operated will drill twice as many wells per rig year at half the rig cost per well, yielding twice the production," they claim.
These two gentlemen have been solving engineering problems for a long time. Allen was a combat engineer in the US Marine Corps during World War II. His long career includes a position as worldwide drilling manager for Amoco Production Company. Armstrong was a naval officer and after the war earned an M.S. in Industrial Engineering from Stanford. He later cofounded Sundowner Offshore Services, which was acquired by Nabors Drilling in 1995.
Allen and Armstrong joined forces to offer rig operating and design consulting services to the industry. They say that their advice can reduce spud-to-release time on multiwell drilling programs by as much as 35% through, as they put it, "the introduction and application of drilling techniques accompanied by time-and-motion principles." They also analyze step-by-step rig moves to reduce release-to-spud time and expense.
In their view, the key is a rig designed with moving in mind. They claim to have designed 12,000-ft (3,658-m) rigs that can move between locations in a single day and say that such a rig, along with drilling advice and personnel training, may offer as much as a 50% reduction in time from spud to spud. Operators would also realize substantial additional production from drilling more wells per year.
Here's how they calculate the 50% reduction in time savings. They call the regime "Performance Drilling," which has three main areas: the application of ExxonMobil's Fast Drilling Program (FDP), rig mobility and operations off the critical path. They assign a value of 35% to FDP, 15% to rig mobility and 5% to off-critical-path operations.
SPE/IADC 92194, a paper authored by ExxonMobil and Totco (which provided instrumentation for FDP), explains how application of the Fast Drill Process through instrumentation, software, hydraulics and training can result in a 35% savings.
Mobility between locations, while not a problem for trailer rigs up to 9,000 ft (2,744 m)capacity, is a significant factor for rigs in the 9,000 ft to 14,000 ft (2,744 m to 4,268 m) range. Most of these "box-on-box" rigs require about 3 to 7 days to mobilize between locations. According to Allen and Armstrong, there are proven designs that emphasize mobility without sacrificing drilling efficiency. These designs enable 1-day, craneless moves of 1,000-hp drawworks, thribbles masts, a couple of 1,000-hp pumps, and all drilling and support equipment.
Savings from off-critical-path operations result from equipment choices and planning. For example, automatic lubrication systems can save time and expense. Holding routine safety meetings pre- or post-tour using only prepared agendas is a simple planning step that can save money over time as well as make the meetings more thorough and effective.
Allen and Armstrong have thought about drilling efficiency in areas beyond moving land rigs. They have updated an idea that has been around for a long time as a solution to drilling wetlands without dredging. For drilling in water as shallow as 2.5 ft (.76 m) they have devised a method that uses crane barges to form a location, with a land drilling rig erected on the barges. A crane at the location handles logistical support at the rig. Shallow-draft,
self-propelled logistical support barges are available as quick assembly modules that will handle 200 tons each. Displacing only about 2 ft (.61 m), they support the operation and transport cuttings to a disposal site.
Industrial engineering as applied to drilling operations by Allen and Armstrong has resulted in a number of methods for increasing efficiency that are worth a look. They can be reached at callen@wziinc.com or jarmstrong@wziinc.com. Besides some interesting ideas, Allen and Armstrong have a bunch of really great stories.