Patriot Bolt Moly-B Thread Compound is a molybdenum disulfide (MoS2) thread lubricant made for controlled makeup and easy breakout after long-term exposure to medium temperature and high load.
It has a specified K-factor of 0.100 and is rated to 750 °F, and it works well on B7, B16 and B8-series studs in carbon or stainless steel flanges. We supply it in three container sizes, alone or with your bolting order.
Moly-B Thread Compound at a Glance
- Lubricant type
- Molybdenum disulfide thread compound
- K-factor
- 0.100 specified (new hardware, good flange condition)
- Solids
- 74%
- Temperature rating
- 750 °F, prorated results to 1500 °F
- Best suited to
- B7, B16 and B8-series studs
- Containers
- Quart, pint and half pint
Why Use Moly-B Thread Compound
- Low, specified K-factor. A K-factor of 0.100 lets a stud reach its target load at lower torque than a higher-friction lubricant.
- Controlled makeup. The molybdenum disulfide solids give smooth, even tightening.
- Easy breakout. Joints come apart cleanly after long service at medium temperature and high load.
- Clean burn-off. No ash or silica is left behind after the oil and grease burn off.
- Rust protection. No rust after 90 days in a humidity cabinet or 90 days in 5% salt spray, which the datasheet rates as equal to 10 years offshore.
Makeup and K-Factor
Moly-B has a specified K-factor of 0.100. That value assumes new hardware and a flange in good condition.
Torque, load and K are linked by T = K × D × F. For the same bolt load, torque scales with K. Torque values worked out for a K of 0.20 would put roughly twice the intended load on a stud lubricated with Moly-B. Always use torque values calculated for the lubricant you apply.
Learn more in our Nut Factor (K) Guide, or run the numbers in the Patriot torque calculator. Our Torque Reference Charts list the K-factor each table assumes.
Typical Properties
| Property | Value |
|---|---|
| Solids type | Molybdenum disulfide |
| Solids content | 74% |
| Temperature rating | 750 °F, prorated results to 1500 °F |
| Solids decomposition | 67% at 750 °F; 33% at 1500 °F |
| Decomposition byproduct | Also a lubricant; remains intact to 1200 °F |
| Appearance | Smooth black paste |
| Blending oil | Synthetic |
| Binder | Complex soap |
| Humidity cabinet, 90 days | No rust |
| 5% salt spray, 90 days | No rust |
Values are typical and taken from the datasheet. Confirm suitability for your application.
Container Sizes
| Container | Net weight |
|---|---|
| Quart | 4.5 lb |
| Pint | 2.25 lb |
| ½ Pint | 18 oz |
Applications
- Flange bolting: A193 B7, A193 B16 and B8-series studs in carbon or stainless steel flanges.
- Medium-temperature, high-load joints that need to come apart cleanly at the next turnaround.
- Joints torqued to a low, known K-factor, where a consistent 0.100 helps reach the target bolt load.
For step-by-step application, see How to Lubricate Flange Bolting.
Datasheet and Safety
The Moly-B datasheet (PB-LD-301) has the full properties, makeup information and container sizes in a printable PDF.
Ask us for the current safety data sheet before first use.
Moly-B Thread Compound FAQ
What is the K-factor of Moly-B?
The specified K-factor is 0.100, assuming new hardware and a flange in good condition.
How hot can Moly-B be used?
It is rated to 750 °F, with prorated results to 1500 °F. Its decomposition byproduct is also a lubricant and stays intact to 1200 °F.
Which studs is Moly-B suited to?
It works well on B7, B16 and B8-series studs in carbon or stainless steel flanges.
Does Moly-B leave residue when it burns off?
No ash or silica is left after the oil and grease burn off.
What sizes does Moly-B come in?
Quart (4.5 lb), pint (2.25 lb) and half pint (18 oz).
Request a Quote
Tell us the product, container size and quantity. You can also add thread lubricant to a stud bolt or nut order. Call (281) 581-0176 or request a quote.
Related: Nickel 328 Anti-Seize · All thread lubricants · Moly-B datasheet (PB-LD-301) · Temperature ratings explained · Nut Factor (K) Guide · B7 stud bolts