PAC · Oil & gas drilling
Oil-Drilling PAC & CMC
Fluid-loss control and viscosity in fresh water to saturated brine — tested to GB/T 5005.
[01]Overview
Sentai polyanionic cellulose (PAC) and drilling-grade CMC control filtrate loss and build viscosity in water-based drilling, completion and workover fluids. High, uniform substitution (DS ≥ 0.9) keeps PAC effective from fresh water to saturated brine and in the presence of calcium. Low-viscosity grades cut fluid loss without thickening; high-viscosity grades do both. Ultra-high-viscosity CMC-5000 to 7000 serve as primary viscosifiers.
- Typical dosage
- 1 – 6 kg/m³ (0.1 – 0.6 %) depending on fluid system — typical field range
- HS code
- 3912.31
- Standard
- GB/T 5005
What it does
- 01Reduces API filtrate loss and builds a thin, low-permeability filter cake
- 02Raises viscosity and carrying capacity for cuttings (HV grades)
- 03Encapsulates reactive shale — supports wellbore stability
- 04Tolerant of salt, hardness and moderate temperature
[02]Grades & specifications
7 grades
Values are specification limits. Typical values and test methods are on the full TDS (Customer Portal or on request).
| Grade | Viscosity · mPa·s | DS | Purity % | pH | Moisture % | Apparent viscosity | Filtrate loss | 600 rpm reading — DI water / 4 % brine / sat. brine | Spec sheet |
|---|---|---|---|---|---|---|---|---|---|
| PAC-LVFluid-loss control · low viscosity | — | ≥ 0.9 | — | — | ≤ 10 | ≤ 40 mPa·s | ≤ 16 mL | — | Spec sheet → |
| PAC-HVFluid-loss control + viscosifier | — | ≥ 0.9 | — | — | ≤ 10 | ≥ 50 mPa·s | ≤ 16 mL | — | Spec sheet → |
| LV-CMCTechnical · fresh water | — | — | — | — | — | — | ≤ 10 mL | ≤ 90 | Spec sheet → |
| HV-CMCTechnical · fresh water to saturated brine | — | — | — | — | — | — | ≤ 10 mL | ≥ 30 / ≥ 30 / ≥ 30 | Spec sheet → |
| CMC-5000Ultra-high-viscosity viscosifier | 5000–6000 @1% | ≥ 0.8 | ≥ 90 | 6.5–8.5 | ≤ 10 | — | — | — | Spec sheet → |
| CMC-6000Ultra-high-viscosity viscosifier | 6000–7000 @1% | ≥ 0.8 | ≥ 90 | 6.5–8.5 | ≤ 10 | — | — | — | Spec sheet → |
| CMC-7000Ultra-high-viscosity viscosifier | 7000–8000 @1% | ≥ 0.8 | ≥ 90 | 6.5–8.5 | ≤ 10 | — | — | — | Spec sheet → |
Viscosity windows
Brookfield viscosity, mPa·s, 25 °C — log scale
Grade map
Each bubble is a grade: degree of substitution on the horizontal axis, minimum purity on the vertical, bubble size by viscosity.
Product photos
The real product.
[03]Applications
Oil & gas drilling
- Fresh-water, seawater and saturated-salt drilling fluids
- Completion, workover and coring fluids
- Cementing slurries and fracturing fluids
- Tunnelling, piling and horizontal directional drilling (HDD)
[05]Packaging & supply
Packed for export.
- Packaging
- 25 kg kraft-composite or PP woven bag with food-grade PE liner · 500 kg / 1 t jumbo bags
- Palletising
- 40 bags = 1 t per pallet, fumigation-free plywood, stretch-wrapped
- Container load
- 20′ GP ≈ 17–20 t · 40′ HQ ≈ 25–28 t
- MOQ
- 1 t for industrial grades · battery grade negotiable
- Lead time
- 7–15 days (stock grades) · 20–30 days (custom)
- Samples
- Free 100–300 g samples, courier collect
- Payment
- T/T 30% deposit, 70% against B/L copy · L/C · D/P
- Incoterms
- FOB · CFR · CIF · EXW
- Documents
- COA · TDS · MSDS/SDS · CO · Form A · Form E
- Inspection
- Customer-appointed SGS / BV inspection accepted
- Port of loading
- Guangzhou — other South China ports on request
[06]FAQ
Drilling PAC/CMC
When should I use PAC-LV versus PAC-HV?+
PAC-LV controls filtrate loss with minimal viscosity increase — ideal for weighted muds where rheology is already high. PAC-HV adds viscosity and carrying capacity as well as fluid-loss control, typical for low-solids and polymer muds.
What is the difference between PAC and drilling CMC?+
Both are carboxymethyl cellulose. PAC has a higher and more uniform degree of substitution (≥ 0.9), which gives it better salt and calcium tolerance; technical drilling CMC is the economical choice for fresh-water systems.
Is your PAC tested to API 13A?+
Sentai drilling grades are specified and tested against China's GB/T 5005 drilling-fluid materials standard (fresh water, 4 % brine and saturated brine). If your tender requires API 13A test data, request it with your enquiry and our lab will confirm.
Qualify it in your process.
Free 100–300 g samples with COA, shipped within days. Tell us your formulation and target viscosity — our applications lab will suggest the closest grade.
Related product families
Products
ST
Battery-Grade CMC
≥ 99.5 % purity anode binder & dispersant for graphite and silicon-carbon electrodes.
R
Instant CMC
Surface-treated CMC that disperses lump-free and reaches full viscosity fast — DS ≥ 0.95.
F
Food-Grade CMC
Cellulose gum (E466) to GB 1886.232-2016 — thickener, stabiliser and protein protector.
P
Paper-Grade CMC
Wet-end, surface sizing and coating colour CMC — viscosity tuned from 7 to 600 mPa·s.
Insights
Related
- Guide
Sep 3, 2026 · 7 min read
PAC-LV vs PAC-HV vs Technical CMC in Water-Based Drilling Fluids
How polyanionic cellulose and technical CMC control fluid loss and rheology, how salt, calcium and temperature change the choice, and which grade fits fresh-water, polymer, weighted and saturated-salt muds.
GuideOct 10, 2026 · 8 min read
How to Choose Battery-Grade CMC for Lithium-ion Anodes: The Specifications That Matter
A practical guide to specifying battery-grade CMC: purity, chloride, DS, viscosity window versus slurry solids, gel count, fibre class, particle size and moisture, plus test methods and an incoming-inspection checklist.
GuideSep 22, 2026 · 8 min read
How to Read a CMC Spec Sheet: Degree of Substitution vs Viscosity vs Purity
What DS, viscosity and purity really tell you about a sodium CMC grade, why 1 % and 2 % Brookfield viscosities cannot be converted, and how DS drives salt tolerance, acid stability and clarity.