The following guidelines should be considered when fishing with overshots: A pack-off should be installed if circulation through the fish is required before POOH. If the hole size is larger than the overshot OD, an oversized guide should be considered. If the pipe is lying in a recess or against the side of the hole, … Fishing with Overshots
The ‘Window Master’ whipstock is a one trip system to mill afull size hole in casing in the required direction. The whipstock is mechanically set and requires a bridge plug to be set at a suitable depth so that weight can be put down on it to initiate the setting process. Dogleg Severity The dogleg … Sidetracking out of Casing with Whipstock
Taper mills can be used for reaming out collapsed or stuck pipe such as casing and liners. They can also be used to clean up permanent whipstock windows, to mill through jagged or split guide shoes and to enlarge restrictions through retainers and adapters. Procedures The following procedure shall be used when milling with taper … Taper Mills
To effectively remove the cuttings while milling stuck pipe, it shall be ensured that: – the yield point of the mud is increased as high as possible prior to commencing milling, taking advice from the fluids engineer. – the flow is turbulent to prevent cuttings from blocking the annulus, (a minimum annular velocity of 115 … Milling Guidelines
Pilot mills are used for milling the following equipment/ material: adapters, liners, casing, swaged casing, stuck drillpipe, wash pipe. The procedure for milling with a pilot mill is as follows: 1. Rotate the string above the fish to establish the free rotating torque. 2. While rotating approximately 30 rpm, slowly enter the fish. Torque shall … Pilot Mill
When milling loose junk, spudding shall be periodically carried out to pound junk down to the bottom of the hole where it can be effectively milled. The following procedure shall be considerd: Loose Junk 1. DETERMINE the neutral point where the mill is just above the junk. MARK the pipe. 2. PICK UP the pipe … Junk Mill
The string shot size shall be determined by the Logging Engineer so that it will be large enough to back-off the joint to be released without splitting the pipe. If the pipe does not back-off after the first shot, the charge can be increased on subsequent runs. The physical size of the primer cord bundle … Backing off Procedures
Detection of the stuck point to locate the lowest possible back-off point can be established by stretching the string and using the stretch charts for drillpipe. This method gives only an approximate value for the free point and shall only be used to locate the approximate stuck point for spotting pipe free pills and to … Stuck Pipe – Free Point Determination
The pipe shall be immediately worked and jarred in the opposite direction to that when it became stuck. That is, if stuck when POOH jar down, if stuck when drilling or RIH jar up. Notes: Pipe shall be pulled to the maximum safe limit previously specified. If the first attempts to free the pipe are … Jarring Stuck Pipe
The pipe shall immediately be pulled to the maximum safe pull specified for the assembly and jarring shall commence. If pulling and jarring are not immediately successful, the pipe shall be slugged and right-hand torque applied in an attempt to free the pipe. Note: The pipe shall continue to be worked and circulation continued while … Freeing Differentially Stuck Pipe