Types of Cement Oil and Gas — Class G/H vs OPC, Primary vs Remedial, and What Belongs in an RFQ
Types of cement oil and gas is a procurement question, not a catalogue label. Buyers search it when they need to map well conditions to slurry class, decide primary vs remedial scope, and put density, BHST, additives, volume, and documents on one RFQ line.
CNPS quotes through cementing for materials and placement-related equipment paths, with adjacent packages under oil & gas solutions. Send a structured brief via request a quote. For mix chemistry background, keep types of cement used in oil and gas as related reading — this page is the buyer/RFQ map.
What “types of cement” means on a well RFQ
In oilfield procurement, “type” usually bundles three decisions:
| Decision | What the buyer is specifying | Fields that belong first |
|---|---|---|
| API oil-well class | Base cement family for the depth / temperature envelope (commonly Class G or H; OPC only when the program allows) | API class, docs list |
| Slurry design | Density, water ratio, retarders/accelerators, fluid-loss, weighting or lightening, LCM, specialty additives | Density window, BHST/BHCT, additives, lab revision |
| Job type | Primary sheath vs remedial plug/squeeze vs specialty isolation | Primary / remedial / plug / squeeze, interval, volume, method |
Do not collapse those into one vague line (“need oil well cement”). Quotes scatter when class, density, and job type are left implied. Process overview: the complete guide to cementing. Isolation intent: zonal isolation solutions.
Class G vs Class H vs OPC — map type to job
OPC (ordinary Portland cement) is general construction cement. Some projects still reference it for shallow or non-critical intervals when the operator’s program allows it. It is not a substitute label for oil-well Class G/H on a deep or high-temperature RFQ.
Class G is the common oil-well base cement many primary and remedial designs start from — used when the program wants a well cement with a known additive response window.
Class H is typically selected when the cementing program names a coarser oil-well cement for deeper / higher-pressure envelopes. Write the class the program names; do not upgrade or downgrade class to chase a catalogue word.
Specialty slurries (lightweight, heavyweight, gas-tight, salt-tolerant, high-temperature, or lost-circulation designs) are additive packages on top of the base class. Name the specialty objective and density/BHST window; do not invent mill or brand identities not on the live CNPS catalogue. Harsh-condition context: cementing for harsh environments.
Primary vs remedial — two RFQ lines when both apply
Primary cementing places the annular sheath that supports casing and provides zonal isolation. RFQ language should include casing size, hole size, interval depths, target density, BHST, volume (or excess %), placement method, and spacer/flush notes.
Remedial cementing covers plug, squeeze, and repair work. Scope fields differ: objective (abandonment plug, squeeze into a channel, kick-off plug), interval, slurry volume, thickening time, and access path (tubing, coiled tubing, or other stated method).
Mixing “cement the well” on one line produces offers that guess primary vs remedial. Split by job type and revision ID. Mud compatibility: how drilling fluids affect casing cement.
RFQ checklist — fields before a quote is useful
Search demand on the cementing topic is real; an RFQ still needs engineering fields, not only a keyword:
- Well and interval — hole size, casing OD/weight/grade if known, TOC / interval depths, inclination if relevant.
- Temperature and pressure — BHST / BHCT, pressure envelope, any gas-migration flag from the program.
- Cement type — API class (G / H / other stated), OPC only if program allows, specialty slurry objective if any.
- Slurry design — density window, additives, lab design revision if available.
- Job type and volume — primary / remedial / plug / squeeze, calculated volume + excess, placement method, spacer/flush.
- Equipment vs materials — materials only, blender/batch path, or combined package via cementing.
- Documents — certificates as project-required, slurry design sheet, thickening-time evidence if required, destination, need-by date.
Attach the cementing program or lab design revision when you have it. CNPS can flag missing fields during review — faster than guessing class or density from a search phrase.
Documentation and compatibility
Offers should confirm which documents travel with the package: class confirmation, slurry design sheet, thickening-time or compressive-strength evidence as required, and any third-party witness the program names. Do not treat a website page as a field certificate. Final approval stays with the project team; the supplier path is to match the written scope.
State mud/spacer chemistry, casing hardware, and whether blending equipment is in scope so quotes do not assume unstated interfaces.
Buyer checklist before you open a quote
- Name the job type (primary vs remedial) and program revision.
- Fill API class, density, BHST, additives, volume — not only “types of cement oil and gas.”
- Separate OPC from Class G/H unless the program explicitly allows OPC.
- Flag equipment vs materials on the cementing path.
- Cross-check isolation and harsh-environment needs on the related guides above.
- Submit through request a quote with destination and document needs.
CTA
Send the cementing program fields and commercial scope together. Start on cementing, then use request a quote with API class, density window, BHST/BHCT, additives, primary vs remedial job type, volume, equipment/materials scope, destination, and documents. That is how types of cement oil and gas search intent becomes a quoteable package. Keep the existing types-of-cement explainer for background; use this buyer guide for the RFQ.
