ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

MDT Sampling - Pipe-conveyed (TLC) MDT Sampling in Gas Wells

Updated on July 10, 2011

This article assumes you are familiar with open-hole (wireline) logging and the Schlumberger Modular Dynamic Tester (MDT) tool.

How do you plan a mega-combo MDT sampling job in a gas well? First and foremost, we need to clearly understand our requirements as the stakeholder.

Typical questions we would ask are:

1. How many sampling points are planned?

2. How many samples will be taken per point, i.e. how many bottles or sample chambers?

3. Are the samples for PVT and/or H2S analysis?

4. Would SPMCs and/or MPSRs be required?

5. Are there any water samples required (in wells with a water leg below the hydrocarbon)?

6. Is wellsite transfer and analysis required?

Most sampling are now done using low-shock sampling method but its worth asking.

These questions will help determine the MDT modules which will be run in the well.

The decision making process regarding when to take a sample should also be clearly defined. The decision is usually taken by the company representative in consultation with the service company expert/reservoir engineer.


The New In-situ Fluid Analyzer (IFA)

The MDT tool-string consists of several different modules, each designed for specific purposes. Each module added to the toolstring should be selected to meet the objective of obtaining PVT quality samples. Modules for analyzing the quality of gas are the CGA (Condensate-Gas Analyzer) and the LFA (Live Fluid Analyzer). Also for pumping out the gas from the formation, the MRPO (MDT Reservoir Pump-out) is required. Other modules required as standard for operating the MDT tool will be specified by the service company. SPMCs (Single Phase Multi-sample Chamber) and MPSRS (Multi-Phase Sample Receiver) are sample bottles (250cc and 450cc respectively) typically used to take PVT quality gas samples. Where wellsite analysis and transfers (SPMC) are required the service company needs to be informed so that the necessary equipment is mobilized to the wellsite.

Pipe-conveyed MDT sampling jobs can go on for more than 2 days therefore personnel from the service companies need to be prepared for 24 hour coverage.

Additional considerations not covered in this article include specifying equipment for tight reservoirs. This covers the type of probe to be used and even using dual-packers. This is a summary of planning for a pipe-conveyed MDT sampling operation, more information should be obtained from in-house experts like the operations petrophysicist, from the service company or from consultants (wireline witnesses).


This website uses cookies

As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

Show Details
HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
LoginThis is necessary to sign in to the HubPages Service.
Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
AkismetThis is used to detect comment spam. (Privacy Policy)
HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
MavenThis supports the Maven widget and search functionality. (Privacy Policy)
Google AdSenseThis is an ad network. (Privacy Policy)
Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
Index ExchangeThis is an ad network. (Privacy Policy)
SovrnThis is an ad network. (Privacy Policy)
Facebook AdsThis is an ad network. (Privacy Policy)
Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
AppNexusThis is an ad network. (Privacy Policy)
OpenxThis is an ad network. (Privacy Policy)
Rubicon ProjectThis is an ad network. (Privacy Policy)
TripleLiftThis is an ad network. (Privacy Policy)
Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
ClickscoThis is a data management platform studying reader behavior (Privacy Policy)