GR Energy Services has developed the ZipLift* assembly to remove and install the nightcap, which protects against debris falling into the well and serves as a critical pressure barrier that maintains well integrity during operations.
When the patent-pending ZipLift assembly is used with the GR ZipLok* and ZipDrop* systems, personnel are completely removed from the red zone, allowing them to install and remove the nightcap, install and remove the lubricator, and drop frac balls without disrupting operations.
The ZipLift assembly straddles the red ZipLok entry guide. When activated, the ZipLok locking ring and the six hydraulic cams are released to allow the ZipLift arms to remove the yellow nightcap. The arms of the ZipLift are above the wellhead only for a short period of time, and because the arms fully retract, crane operations can be conducted without restriction.
Step 1 – While wireline is running in the hole, the nightcap is stored to the side. The large pistons are retracted, which prevents the assembly from being damaged by the lubricator when coming off or stabbing in the well.
Step 2 – The large pistons are fully extended when installing the nightcap, allowing it to clear the tulip top while being positioned over the ZipLok remote wellhead rig-up/rig-down equipment.
Step 3 – Once the large pistons are fully extended, the small pistons are retracted until the nightcap is centered over the top of the ZipLok equipment.
Step 4 – The nightcap is then lowered into the ZipLok body and secured with six locking segments. The procedure is carried out in reverse to remove the nightcap.