Discounted effect, ICVs performance

		500
Дисконтированный•Discounted effect, $эффектmillion ,		400
		300
	млн. $	200
		100
		0
		0	5	10		15	20	25
		-100
				•		Time, years
					Время, лет

•Prepared by Alexey Khrulenko, 2011

Part II - Well completion design				#5
#1	#2	#3	#4

Position of ICV in one of the wells

•Prepared by Alexey Khrulenko, 2011

Section 2

Well perforation

Part II - Well completion design

Well perforation

Perforation technique

Perforation design

Evaluating efficiency of perforation

−Depth of penetration

−Shot density

−Phasing

Part II - Well completion design

Well Perforation

Liner

Part II - Well completion design

Well Perforation

Unfired shaped charge

Liner

Charge detonates.

Liner begins to collapse

High pressure jet forms.

Pressure wave with p=500000 bar travels at9000 km/hour

Part II - Well completion design

Well Perforation

Plasma jet

Jet becomes more developed. Pressure causes jet velocity to increase to 25000 km/hour

Jet is fully formed.

Tip of jet pierces and compacts the casing, cement, and formation

with 350000 bar

Formation

Hollow Cement carrier Casing

Part II - Well completion design

Well Perforation

Perforation performance depends on a number of factors, among which most important are:

Charge type

Gun size

Shot density

Phasing

Conveyance method

Wellbore fluids

Part II - Well completion design

Well Perforation

Perforation cleaning

Failure to remove debris and compacted zone can reduce the potential productivity of a well as much as 80%!

The following methods can be used for perforation cleaning:

Acidizing

Washing

Backsurging

Underbalance perforating

Part II - Well completion design

Well Perforation

Perforation design

Important parameters of perforation design are:

Shot density

Shot phasing

Depth of perforation

Part II - Well completion design

Well Perforation

Perforation design

Part II - Well completion design

Well Perforation

	Pressure distribution along the perforation tunnel
	175
	170
bar	165											pe=200 bar
Pressure,
	160
	155							Pressure distribution within drainage area
						180
	150				bar	175
	0,00	0,05	0,10	0,15		170	0,20					Real well
		Length of perforation tunnel, cm			Pressure,	165
												Ideal well
						160
						155
						150
						0,10		0,20	0,30	0,40	0,50	0,60
									Distance from wellbore, m

Part II - Well completion design