scope:

a. The purpose of this bulletin is to provide information on two types of thread compounds recommended for casing and tubing connections in high-pressure well service. This bulletin is for the convenience of purchasers and manufacturers in ordering and producing thread compounds and is not intended to inhibit purchasers and producers from purchasing and producing thread compounds meeting specifications other than those contained herein.

b. These compounds were originally developed by the Mellon Institute of Industrial Research, under an API sponsored research project, to meet the following objectives:

1. Adequate lubricating qualities to prevent galling in threaded connections during make-up.

2. No tendency to disintegrate nor undergo radical change in volume at temperatures up to 300 F.

3. No tendency to become excessively fluid at temperatures as high as 300 F.

4. Sealing properties sufficient to prevent leakage at temperatures as high as 300 F.

5. Absence of any deleterious instability and of any drier or hardener that will evaporate or oxidize, thereby changing the thread-compound properties.

6. Resistance to water absorption.

7. Sufficient inert filler to prevent leakage of API round-thread casing and tubing joints under pressure as high as 10,000 psi.

8. Readily applicable by brush to pipe joints in cold weather.

These objectives are broadly stated and it is recognized that the ability of a thread compound to meet some of these objectives can be measured only by service experience. Both modified and silicone thread compounds have demonstrated over a period of years that, in general, the objectives have been satisfactorily achieved under service conditions.

The presence of silicones improves low-temperature properties and may improve application to threads wet with water. Silicones do not necessarily improve sealing or anti-galling properties of thread compound. Sealing properties of thread compound are dependent upon the specific combination, particle sizes, and quantities of designated solids.

The specific formulations developed by Mellon Institute have been modified with respect to the grease base. The original Mellon Institute formulas require a specific soap base and process oil to form the grease. The formulas have been changed so as to permit use of any grease base which, when combined with the solids, meets the performance requirements applied to the finished thread compound. Control and performance tests which measure definite required characteristics of thread compounds are specified in Section 2.

c. Definitions

Shall -Shall is used to indicate a provision is mandatory.

Should - Should is used to indicate that a provision is not mandatory but recommended as good practice.

May - May is used to indicate that a provision is optional.

d. Referenced Standards

1. General. This specification includes by reference, either in total or in part, other API, industry and government standards listed in Table 1.0.

2. Requirements. Requirements of other standards included by reference in this specification are essential to the safety and interchangeability of the equipment produced.

3. Equivalent Standards. Other nationally or internationally recognized standards shall be submitted to and approved by API for inclusion in this specification prior to their use as equivalent standards.