DPI Inflatable Packers

Model#

  1. DPI- PA3630-PCT – 3″-6″ x 30” Packer Assy.
  2. DPI-PA3430-PCT – 3″-4″ x 30″ Packer Assy.

DPI- PA3630-PCT – 3″-6″ x 30” Packer Assy.

DPI-PA3430-PCT – 3″-4″ x 30″ Packer Assy.

Inflatable Packer Operating Procedures

Basics:
The DPI Inflatable Packer is made up of four major components: FIXED HEAD; CENTER TUBE; GLAND ELEMENT; and SLIDING HEAD. The gland element is the key component that expands as air or water pressure is applied, and contracts as pressure is decreased. The packer gland element used is made of natural rubber with two layers of steel cable reinforcement. It expands evenly within the hole which allows the outer rubber cover to protrude into borehole imbalances, thereby causing a tight seal over the full length of the packer gland element. The packer heads both have ports to allow concurrent use of multiple packers. The inflation air or fluid is transmitted thru the packer in the annulus between the center tube and the gland element.
You will notice on the perimeter of the fixed head a stamped indication of the maximum internal pressure that can be applied when the packer is inflated to its maximum diameter. This is the pressure at which the maximum gland element expansion occurs. The warranty will be voided if excess pressure is used. (Within an open or cased borehole of known diameter, it is possible to exceed the rated free-air pressure without jeopardizing the integrity of the packer. Please refer to the pressure curve charts.
If it is necessary to test or inflate the packer above ground, do not test or inflate above 25% of the unconfined rated pressure that is stamped on the fixed head. It is imperative that everyone stay clear of either end of the packer if testing or inflating above ground.
WARNING: When using compressed gasses, such as nitrogen or compressed air, please use extreme caution. They are extremely dangerous and misuse of the gasses or the packers that they operate has potential to cause serious injury. Follow instructions closely as directed on the containers.
Using either Air or Water to inflate the packer is satisfactory. The most common choices for inflation would be nitrogen, compressed air or water. When using air inflation, nitrogen is recommended because it is the cleanest Compressed air may be used, but it is necessary to filter it before inflating the packer to prevent oil and dirt from getting inside the gland which causes accelerated break down of the rubber.

Before the first use of the packer, all connections made on site need to be tested at low pressure for leaks. It is also necessary to have the gauge or regulator on the source of inflation pressure tested and calibrated to insure the readings are accurate. A common cause of packer failure is a faulty or improperly calibrated regulator.

Operating a Single Packer
It is most common to have the fixed head up during single packer operation. Connect the inflation tube to the fixed packer head via the connector. Using drill rods, grout rods or iron pipe, insert the packer to the desired depth and then connect the other end of the inflation tube to the pressure regulator.
Back the regulator adjustment lever to zero pressure and open the supply valve on the source of inflation pressure. The pressure should be slowly and gradually increased to the packer by adjusting the regulator. REMINDER: the final gauge pressure should never exceed the total of rated packer pressure plus hydrostatic pressure above the packer. We are available to answer questions about inflation pressure/procedures, please contact us. At this point, you should have the packer inserted and inflated properly, complete your testing or grouting at this time. When complete, release the inflation pressure.

PACKER INFLATION PRESSURE FORMULA
G = Inflation pressure at gauge (PSI)
DP – Depth to top of packer (feet)
Dw = Depth to static water level in well (feet)
Sp = Unconfined packer pressure rating for the well size (PSI)
PP = Injection pump pressure (PSI)
(1) To calculate Packer Inflation Pressure for a withdraw test (pump out):

G = [(DP-DW) x .43] + Sp + [(DP-DW) X .43 x .2]

NOTE: This total must not exceed confined packer pressure rating for the well size.

(2) To calculate Packer Inflation Pressure for an injection test (pump in):

G= [(DP x PSI per foot of Injected Fluid*) + Sp + PP ] x 1.1 *.43 for Water or .5 for grout
NOTE: This total must not exceed confined packer pressure rating
plus (DP- DW) X .43