taper tap

Taper Taps: The Unsung Heroes of Well Completion

In the world of oil and gas drilling, the unexpected can and often does happen. One such scenario involves the unfortunate loss of a hollow fish, a vital component used to connect drill strings and downhole tools. When a hollow fish becomes stuck in the wellbore, it can bring drilling operations to a screeching halt. Thankfully, there's a tool designed to tackle this situation – the taper tap.

What is a Taper Tap?

A taper tap is essentially a specialized threaded tool with a gradually decreasing diameter from the top. It acts as the male counterpart to a die collar, another crucial component in well completion. The die collar, essentially a threaded sleeve, is typically attached to the bottom end of the hollow fish.

How Does it Work?

When a hollow fish becomes stuck, the taper tap is lowered into the wellbore and engaged with the die collar. As the taper tap is rotated, its cutting threads engage with the die collar, gradually cutting into the metal and establishing a strong grip. This grip allows the taper tap to be used as a retrieval tool, pulling the fish free from the wellbore.

Key Features of a Taper Tap:

Tapered Design: This allows for easy entry into the hollow fish and ensures a secure grip even with minimal engagement.
Cutting Threads: The threads are designed to cut into the die collar, creating a strong mechanical bond.
High Strength Material: Taper taps are made from high-quality materials, capable of withstanding the rigors of downhole environments.
Variety of Sizes: Taper taps are available in different sizes to accommodate various die collars and fish types.

Benefits of Using a Taper Tap:

Efficient Retrieval: The taper tap provides a reliable and efficient method for recovering lost hollow fish.
Cost-Effective: Using a taper tap avoids the expensive and time-consuming alternative of drilling a sidetrack or abandoning the well.
Minimizes Downtime: The quick retrieval of the fish minimizes downtime and ensures continued drilling operations.
Safe and Reliable: The secure grip of the taper tap ensures the safe and controlled retrieval of the lost fish.

In Conclusion:

The taper tap is an essential tool for well completion operations, playing a vital role in the successful recovery of lost hollow fish. Its unique design and robust construction make it a reliable and cost-effective solution for this common drilling challenge. Next time you hear about a fish being pulled out of a well, remember the unsung hero – the taper tap – silently working behind the scenes to keep drilling operations moving forward.

Test Your Knowledge

Taper Taps Quiz

Instructions: Choose the best answer for each question.

1. What is the primary function of a taper tap?

a) To connect drill strings and downhole tools. b) To retrieve a stuck hollow fish from the wellbore. c) To prevent the loss of a hollow fish. d) To drill a sidetrack in case of a lost fish.

Answer

b) To retrieve a stuck hollow fish from the wellbore.

2. What is the male counterpart to a die collar?

a) Drill string b) Hollow fish c) Taper tap d) Sidetrack

Answer

c) Taper tap

3. How does a taper tap achieve its grip on a die collar?

a) By using magnets. b) By using hydraulic pressure. c) By using its tapered design and cutting threads. d) By using a special type of glue.

Answer

c) By using its tapered design and cutting threads.

4. What is a major benefit of using a taper tap?

a) It allows drilling operations to continue uninterrupted. b) It prevents the loss of a hollow fish. c) It makes drilling faster and easier. d) It can be used to drill sidetracks.

Answer

a) It allows drilling operations to continue uninterrupted.

5. What material are taper taps typically made from?

a) Plastic b) Aluminum c) High-strength steel d) Rubber

Answer

c) High-strength steel

Taper Tap Exercise

Scenario: You are working on an oil rig, and a hollow fish becomes stuck in the wellbore. The fish is connected to a die collar with a 3-inch diameter.

Task: You need to choose the appropriate taper tap to retrieve the stuck hollow fish. The available taper taps are:

Taper Tap A: 2-inch diameter, 10-inch length
Taper Tap B: 3-inch diameter, 15-inch length
Taper Tap C: 4-inch diameter, 20-inch length

Instructions:

Explain why you would choose the specific taper tap.
Describe the steps you would take to use the taper tap to retrieve the fish.

Exercice Correction

**1. Choosing the taper tap:**

The correct choice is Taper Tap B, with a 3-inch diameter. Here's why:

The die collar is 3 inches in diameter, so the taper tap needs to be at least 3 inches in diameter to engage with it.
A smaller taper tap (Taper Tap A) wouldn't provide a secure grip.
A larger taper tap (Taper Tap C) might not be able to fit into the wellbore if there's limited space.

**2. Steps to retrieve the fish:**

**Lower the taper tap:** Carefully lower the taper tap into the wellbore using a drilling cable.
**Engage the die collar:** Once the taper tap reaches the die collar, rotate it to engage the cutting threads.
**Apply tension:** After the taper tap has a secure grip, apply tension to the cable to start pulling the hollow fish free.
**Retrieve the fish:** Continue pulling with controlled force until the fish is fully retrieved from the wellbore.
**Inspect the fish:** Once the fish is out, inspect it for any damage and make sure it can be reused or needs to be replaced.

Books

"Petroleum Engineering Handbook" by Tarek Ahmed: A comprehensive resource on drilling and well completion techniques. This book should cover the use of taper taps.
"Drilling Engineering" by Robert E. Kick: Another detailed handbook on drilling practices, likely containing information on taper taps and their application.
"Well Completion Design and Operations" by Robert M. Holditch: This book focuses on well completion techniques, including equipment and procedures, potentially offering insights into taper tap usage.

Articles

"Lost Circulation Control" by SPE: This article from the Society of Petroleum Engineers (SPE) might discuss different methods for dealing with stuck equipment, including taper taps.
"The Use of Taper Taps for the Retrieval of Lost Hollow Fish" (Search online databases like OnePetro, SPE, or Google Scholar): While this article might not exist, a search with this title could uncover relevant research papers or case studies on taper taps.

Online Resources

Oilfield Glossary: This comprehensive dictionary defines key terms used in the oil and gas industry, including likely definitions of "taper tap" and related components.
Websites of drilling and well completion equipment suppliers: Companies specializing in downhole tools often have technical resources and product catalogs that could detail the use of taper taps.

Search Tips

Use specific keywords: Include terms like "taper tap", "hollow fish", "retrieval tool", "well completion", "stuck equipment", "drilling operations", "die collar" in your searches.
Combine keywords: Experiment with different combinations of these terms to narrow down your results.
Use quotation marks: Enclose specific phrases like "taper tap" or "hollow fish" in quotation marks to find exact matches.
Search for PDF documents: Add "filetype:pdf" to your search to find more technical documents and manuals.