Monday, 14 February 2011

Blind Box

Many kinds of the Standard Service Tools are using for fishing jobs, among other things shall be as follow as Blind Box.
The Blind Boxes are used when heavy downward jarring is required to dislodge a fish, or pushes something down the hole. It is flat on bottom and hardened to reduce wear and damage.
It is available in a range "1.57 inch O.D - 5.384 inch O.D" of sizes to suit the application.
As a 'Cutter Bar', it is made up below a piece of stem and rope socket then dropped in the well to cut wire downhole.
The purpose of the Cutter Bar is to cut the wire at the top of the rope socket of a toolstring which cannot be retrieved.
o Stem: select the length to suit well conditions. Heavy oil will require a long length of stem. Extreme caution must be taken in gas wells as very short lengths of stem (or just the rope socket and blind box) will travel very quickly.
o Blind_Boxes (BB): size (OD) to suit ID of tubing and OD of rope socket.
- Minimum size determined by distance from tubing wall to completely cover the wire diameter.
- Maximum size determined by fluid bypass round the
Blind box and by the nipple ID's
The worst possible case should be assumed with the toolstring lying against one wall of the tubing.
Diameter of blind box must be large enough to prevent the cutter bar from passing down the side of the toolstring.
Available Now! The drawings of Blind Box with size O.D:
1.57", 1.77", 1.97", 2.17", 2.28", 2.36", 2.52", 2.56", 2.76", 2.80", 2.87", 3.00", 3.15", 3.35", 3.50", 3.54", 3.74", 3.78", 3.86", 3.94", 3.978", 4.25", 4.33", 4.50", 4.53", 4.65", 4.92", 5.00", 5.384", 5.80", 8.00".