FISHING TOOLS - National Oilwell Varco
FISHING TOOLS - National Oilwell Varco
FISHING TOOLS - National Oilwell Varco
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
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<br />
550°F. These Casing Patches are very simple to operate. The Patch is assembled, attached<br />
to the running string and lowered over the washed over string. The running string is lifted,<br />
allowing the outer body parts to move up-hole while the Grapple and Carrier remain in position.<br />
This 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. Cement<br />
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 />
Center Seal Ring<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 are<br />
essentially the same as the standard Bowen Packer Type Casing Patch, with the added feature of a long Top Extension. Casing Patches are<br />
available in a complete range of sizes from 52” through 13a” casing. Additional sizes to meet specific requirements will be made on special<br />
order. The Top Extension is manufactured from casing where practical to reduce cost to a minimum. Where hole sizes will not permit the<br />
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 in<br />
cement, an expensive and time consuming fishing job could result. In place of conventional fishing, the operation may be salvaged by using<br />
a Bowen Casing Patch in the following manner. The first collar below the wellhead may be located and the casing cut. The upper portion<br />
of the casing is removed from the well. The remaining portion of the casing is engaged and packed off, and is then engaged with a Bowen<br />
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 Wellhead<br />
Casing Patches.<br />
Guide<br />
Lead Seal Cementing Casing Patch<br />
Lead Seal Cementing Casing Patches<br />
Casing O.D. 2a 2d 32 4 42 5 52* 5w 6 6s 7 7s 8s 9s 10w 11w 13a<br />
Patch O.D. 48 4s 54 5w 62 6w 7v 7w 8 8s 98 9d 118 11, 13s 14w 16s<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 />
Underwater Wellhead Casing Patches<br />
Casing Size 52 52 7 7 9s 9s 10w 10w 13a 13a<br />
Casing Patch O.D. 7D 6m 8c 8c 118 118 14a 12c 17 158<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 />
Packer<br />
Protector<br />
Adapter<br />
Sub<br />
Underwater Wellhead Casing Patches:<br />
Alloy Extension (left) and Casing Extension (right)