150 Series Downhole Overshot for Well Drilling and Fishing

• Customization: Available
• After-sales Service: 1 Year
• Warranty: 1 Year
• Model NO.: VSP-OS
• Certification: CE, ISO 9001:2000, ISO 9001:2008, API
• Power Source: Hydraulic
• Operation Pressure: Atmospheric Pressure
• Applicable Medium: Mud, Water, Natural Gas, Crude Oil
• Structure: Vertical
• Material: Alloy
• Document: Test Report
• Thread Type: API or GOST
• Spare Parts: in Supply
• Painting: Customized
• Transport Package: Wooden Case
• Specification: 3.1/2"--6.5/8"
• Trademark: VSP
• Origin: China
• HS Code: 8431431000
• Production Capacity: 3000PCS/Year
• Package Size: 80.00cm * 20.00cm * 20.00cm
• Package Gross Weight: 100.000kg

Product Description

An Overshot as downhole tool is used in fishing operations to engage on the outside surface of a tube or tool. A grapple, or similar slip mechanism, on the overshot grips the fish, allowing application of tensile force and jarring action. If the fish cannot be removed, a release system within the overshot allows the overshot to be disengaged and retrieved.
The overshot is designed to assure positive external engagement over a large area of the fish and is ruggedly built to withstand severe drilling jarring devices actions and pulling strains without damage or distortion to either tool or fish.

When you are designing an overshot assembly, you will need to select the:

• overshot size
• connection on the top sub
• grapple type
• grapple size
• pack-off type
• grapple control type
• overshot guide type
• overshot extension size.

 

 

Releasing The Overshot In Drilling

There are several methods for releasing overshot fishing tools, including releasing:

• Downhole on a production rig
• Down hole with the Kelly in the string and bushing in the rotary table l down hole with drill pipe in the rotary table
• On the surface with the fish in the rotary table
• Down hole on a production rig.

Releasing The Overshot In Fishing

1. Bump or jar down on the string to break the freeze between the overshot bowl and the grapple. Note: You will know that the freeze is broken when you are able to turn to the right.
2. Once rotation has been established, slowly pick up while continuing to rotate. This will allow the left hand wicker in the grapple to walk off the fish.

Releasing The Overshot on a production rig

1. Bump down on the overshot and turn it with the tongs. Note: For the most part, you will be depending on hydraulic tongs for rotation.
2. Pick up slowly and turn the string until it is free of the fish, being careful not to pull up to hard on the grapple.

Specifications (150 Series):

Model	O.D.(mm)	Max.catch size(mm)		API Connection	Model	O.D.(mm)	Max.catch size(mm)		API Connection
		Spiral grapple	Basket grapple				Spiral grapple	Basket grapple
LT-T89	89	60.3	47.6	NC26	LT-T194	194	159	141	NC50
LT-T92	92	73	63.5	NC26	LT-T200	200	159	141	NC50
LT-T95	95	76.2	66.6	NC26	LT-T206	206	178	163	NC50
LT-T102	102	73	60.3	NC26	LT-T206A	206	168	152	NC50
LT-T105	105	85.7	73	NC31	LT-T219	219	178	159	NC50
LT-T114	114	89	75	NC31	LT-T232	232	203	187	NC50
LT-T117	117	89	78	NC31	LT-T244	244	206	184	6 5/8 REG
LT-T127	127	95	80	NC38	LT-T260	260	219	200	6 5/8 REG
LT-T143	143	120.6	102	NC38	LT-T270	270	228.6	209.6	6 5/8 REG
LT-T152	152	128	111	NC38	LT-T273	273	241.3	216	6 5/8 REG
LT-T168	168	127	114	NC50	LT-T286	286	244.5	225.4	6 5/8 REG
LT-T168B	168	139.7	120.6	NC50	LT-T298A	298	257	238.1	6 5/8 REG
LT-T181	181	146	127	NC50	LT-T340	340	286	260	6 5/8 REG