Zonal Equalisation Device

What is it ?

The Red Spider Technology Zonal Equalisation Device is a positive sealing plug that holds pressure from either direction but is opened when an excess of pressure is seen from below the device. This device is particularly useful when run in application where a lower zone requires to be separated from an upper zone. Positioned between the two zones the device will allow the upper zone to be flowed with out any commingling from the lower zone. By “drawing down” the upper zone pressure and hence increasing the differential from below to above allows the mechanism to shear out and the device to permanently open allow the two zones to commingle.

The device is typically attached to a Retrievable Packer which in turn is deployed into the well on either slick-line, e-line, coiled tubing or work string. Once opened the device cannot be re-closed.

When would I use it ?

The Zonal Equalisation Device can be used in the majority of temporary plugging operations where, once a certain pressure is over come from below the device is required to open:

• Set between zones, the device can allow the upper zone to be cleaned up without commingled flow from the lower zone – this is particularly useful in horizontal wells where the heal requires to be cleaned up in preference to the toe
• To prevent cross flow between a higher pressure lower zone and a lower pressure upper zone – once the upper zone has sufficiently depleted or is physically drawn down will the device open