FISHING TOOLS - National Oilwell Varco
FISHING TOOLS - National Oilwell Varco
FISHING TOOLS - National Oilwell Varco
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46<br />
Casing Patches<br />
Bowen ® Lead Seal Cementing Casing Patches<br />
NOV Downhole Bowen ® Lead Seal Cementing Casing Patches are designed to form a<br />
permanent sealed connection between two strings of tubing or casing and cement them<br />
together in a single run. These Patches incorporate the proven Bowen ® compression-type<br />
multiple lead seal assembly and a valving method which allows it to be cemented in place<br />
immediately after it is set. The primary seals are cast from commercially pure lead, which is<br />
impervious to most well fluids and gases. These seals are effective in temperatures up to 550°F.<br />
These Casing Patches are very simple to operate. The Patch is assembled, attached to the<br />
running string and lowered over the washed over string. The running string is lifted, allowing<br />
the outer body parts to move up-hole while the Grapple and Carrier remain in position. This<br />
compresses the Lead Seals, forming an initial seal.<br />
The running string is then lowered, telescoping the carrier and stinger upward in the outer<br />
body parts and opening the valve formed between the integral lower seal and the stinger.<br />
Cement is immediately pumped through this valve, cementing the Patch and running string in<br />
place. After cementing, a moderate pull is again applied to the running string and maintained<br />
during the cement curing interval.<br />
Send for Technical Manual No. 6460 which includes complete descriptions of construction, operation, maintenance,<br />
and parts listing for Bowen ® Lead Seal Cementing Casing Patches.<br />
Top Sub<br />
Bowl Seal<br />
Bowl<br />
Grapple Carrier<br />
Grapple<br />
Grapple Control<br />
Lead Seal Assembly<br />
Stinger Retainer<br />
Stinger<br />
Bowl Seal<br />
Control Set Screw<br />
End Seal Ring<br />
Lead Seal<br />
Lead Seal Cementing Casing Patches<br />
Casing O.D. 2 3/8 2 7/8 3 1/2 4 4 1/2 5 5 1/2* 5 3/4 6 6 5/8 7 7 5/8 8 5/8 9 5/8 10 3/4 11 3/4 13 3/8<br />
Patch O.D. 4 1/8 4 5/8 5 1/4 5 3/4 6 1/2 6 3/4 7 7/16 7 3/4 8 8 5/8 9 1/8 9 7/8 11 1/8 11 15/16 13 5/8 14 3/4 16 5/8<br />
Complete Assembly Part No. 40514 41209 41210 40596 40619 40649 38179 41088 40679 40858 40859 40869 41004 41085 41086 41089 41087<br />
Weight 102 131 143 156 217 224 261 258 273 285 337 379 507 717 816 956 1363<br />
*This size available for H2S service. Complete assembly No. 146503.<br />
Bowen ® Underwater Wellhead Casing Patches<br />
NOV Downhole Bowen ® Underwater Wellhead Casing Patches are engineered to allow casing to be salvaged during landing operations<br />
that would otherwise necessitate expensive underwater washover and pulling operations. Bowen Underwater Wellhead Casing Patches<br />
are essentially the same as the standard Bowen ® Packer Type Casing Patch, with the added feature of a long Top Extension. Casing<br />
Patches are available in a complete rangeof sizes from 5 1/2” through 13 3/8” casing. Additional sizes to meet specific requirements will<br />
be made on special order. The Top Extension is manufactured from casing where practical to reduce cost to a minimum. Where hole sizes<br />
will not permit the inexpensive extension, alloy tubing is used. In most cases, extensions are available in any required length.<br />
Sometimes during landing operations the casing being landed gets stuck off bottom. It this happens while the casing is being floated down<br />
in cement, an expensive and time consuming fishing job could result. In place of conventional fishing, the operation may be salvaged by<br />
using a Bowen ® Casing Patch in the following manner. The first collar below the wellhead may be located and the casing cut. The upper<br />
portion of the casing is removed from the well. The remaining portion of the casing is engaged and packed off, and is then engaged with<br />
a Bowen ® Releasing Spear and pulled up into the path a sufficient distance to insure proper tension in the casing string.<br />
Send for Bowen ® Technical Manual No. 6480 which includes complete descriptions of construction, operation, maintenance, and parts listing for Bowen ® Underwater<br />
Wellhead Casing Patches.<br />
Underwater Wellhead Casing Patches<br />
Casing Size 5 1/2 5 1/2 7 7 9 5/8 9 5/8 10 3/4 10 3/4 13 3/8 13 3/8<br />
Casing Patch O.D. 7 21/32 6 13/16 8 5/16 8 5/16 11 1/8 11 1/8 14 3/8 12 5/16 17 15 1/8<br />
Type of Extension Casing Alloy Casing Alloy Casing Alloy Casing Alloy Casing Alloy<br />
Length of Extension (ft) 10 10 10 10 10 10 10 10 10 10<br />
Type of Casing Patch<br />
Complete Assembly<br />
Packer Packer Packer Packer Packer Packer Packer Packer Packer Packer<br />
Part No. 47778 47772 44960 47767 45000 47758 47736 47730 43379 40398<br />
Weight 500 455 400 730 645 1145 1625 1325 1300 1980<br />
Optional Extra Accessories<br />
Dressing Mill (Accessory)<br />
Part No. 44822 — 49249 54341 54343 49251 51699 — 54338 54516<br />
Weight 55 — 101 120 130 127 125 — 140 250<br />
Top Sub<br />
Top Extension<br />
Shear Pin<br />
Shear Pin Plug<br />
Packer<br />
Bowl<br />
Grapple<br />
Control Packer<br />
Guide<br />
Center Seal Ring<br />
Guide<br />
Lead Seal Cementing Casing Patch<br />
Packer<br />
Protector<br />
Adapter<br />
Sub<br />
Underwater Wellhead Casing Patches:<br />
Alloy Extension (left) and Casing Extension (right)