All,One of our client is requesting for a conventional Tail slurry at 1.7 SG across the pay zoneMy concern is about the Compressive Strength development as it will be difficult to achieve 2000 psi before perforating with guns for completingCould you please share your experience or any design with similar density and BHCT ranging from 40 to 50 degCCopy that CRETE systems are not required, suggestions on additives to build up CS in such a case are welcomeKind regardsRodrigue

Rodrigue,Good day. I surely don't have an exact answer to your question, however I would like to raise a few morequestions to help todefineyour question more precisely.(1)How many hours areavailable for cement to set before client perforate?(2)How many hours have you got with current recipe? And what additives have been used?(3)What's the BHST?(4)Do you have a readily available lab? Can you post an example of your design parameters and slurry lab report with UCA test? Usually I will persuade my client with a sound lab report showing him whether his request is a go or a no-go.If you can post more information, I believe our CemBB expert will provide more help on this.Have a good day !Liu Zheng Kui

LiuThanks for replyingBHST ranges from 60 to 65 degCTT will be around 4-5 hoursClient use to perforate after 30 to 40 hours, sometimes moreNo lab test has been run yet as I just got the request. To let you know Ill be going with the following design D047 + D020 + D500 (or D168) + D081 + Dispersant (if needed), and see what happensClient has been already briefed on how difficult will be to get an acceptable CS with 1.7 SG conventional slurry and I do agree with you for proofs, that what I am going to provide later on. From now, I am just seeking for advices.RegardsRodrigue

Rodrigues,please check intouch ticket B038 Tech Memo (#2036929) and Improvement in Compressive Strength for KOPs (#3937388), adding B038 you should have improvement of CS.

RodrigueAddition of D154 (dry) or D155 (liquid) will help out with CS increase. RgdsOlga Ivanova General Field EngineerSchlumbergerWell Services

Rodrigue,Have you considered using D186 in your system? This should help speed up your strength development.MArk

Rodrigue,Is your slurry design with Class G cement? If you could switch to Class A cement neat or Class A blended with 25%BWOC of fly ash(D035), the 1.7 SG slurry should give you well over 2000 psi in 30-40 hours at your BHST(even at your BHCT) which you can confirm by running lab tests at your district lab. This would also make your design more cost effective as you wont need to add D186 or other CS enhancement additives.Besides, your proposed slurry design(if Class G) may also give you close to the CS you are looking for at your BHST after 36-40 hours but this would depend on the quality of the cement(aging wise) that you would use. Again, this could only be verified by the lab test that you are doing. As suggested, additives like D186, D077(liquid S001) may help. You may also look at replacing D020 extender with D075(do not use both together) as D020 interferes with fluid loss control thereby requiring more amount of D500 and not making it cost effective.Prioritize your design options based on what you have in inventory for laboratory testing so you would get the desired results sooner.Respond to me directly if you need some designs with Class A cement.Regards,RLASchlumberger Australia PTY LTDRoshan Amesur34 Carmichael stChinchilla QLD 4413Australia Mobile:+61-409-383-243