Trenchless Pipe

AMERICAN Ductile Iron Specials
Ductile Iron Trenchless Pipe

MT^TM Push Pipe

By its nature, ductile iron pipe possesses tremendous columnar and tensile strength, which makes it a superior material for trenchless applications. AMERICAN offers four joints designed for use in direct jacking, trenchless pipeline replacement, pipe bursting, and microtunneling installation. MT^TM Push Pipe is used primarily for pressure applications, and GS® Push Pipe is used for gravity sewer applications. Fastite Joint Push-Bar Pipe allows the Fastite Joint to be used in trenchless applications using direct jacking or pushing. Flex-Ring® joint pipe with its positive, flexible joint restraint has been used extensively in pipe-pulling applications utilizing horizontal directional drilling and some pipe bursting installation methods. A "Suggested General Guidelines for Horizontal Directional Dreilling (HDD) Installations of Ductile Iron Pipes" document is available from AMERICAN, or online in pdf format from www.acipco.com/adip. With spigots ahead, the low-profile Flex-Ring® bell assembles quickly and offers a smooth transition during pipe pull-back. AMERICAN offers a Flex-Ring® pulling bell assembly specifically designed for this installation method.

MT^TM Push Pipe is a bell-less ductile iron pipe capable of functioning in either gravity or pressure applications up to 350 psi in 4"-12" sizes or 250 psi in 14"-16" sizes. The joint is formed by counterboring both ends of an extra thick (Special Thickness Class 55) ductile iron pipe. An independent, internal, stainless steel coupling with double 1/4" O-Ring grooves is utilized in this joint configuration. The MT^TM Push Pipe was developed primarily as a pipe to be used in the microtunneling process which requires the pipe to resist significantly large pushing loads.

GS® Push Pipe is also a bell-less ductile iron pipe, also used in microtunneling and other pushing applications, capable of providing a positive seal for gravity or low head applications up to 100 feet (43 psi) in 4"-16" sizes. It consists of an extra thick (Special Thickness Class 56) pipe machined to form an internal bell and double O-Ring gasketed spigot. Because the joint is precision machined, it efficiently transfers the jacking loads through the joint, therefore maximizing the potential length of installation.

Candidate ductile iron pipe for both MT^TM Push Pipe and GS® Push Pipe fabrication is manufactured and tested in accordance with ANSI/AWWA C151/A21.51. Counterbored joint surfaces are covered with an epoxy coating. The pipe comes in 20' or less standard nominal laying lengths.

Push-Bar Pipe employs an economical adaptation of the premier AMERICAN Fastite Joint to transfer jacking loads from the pipe barrel directly to the face of the bell. It consists of a high-strength, alloy steel ring, the "push-bar," shop welded to the standard Fastite pipe spigot. This ring is made of the same material that has been used successfully in AMERICAN's Lok-Ring and other restrained joints for over 30 years. A cushioning compression ring, made of compressible wood products, fits between the push-bar and the pipe bell for added assurance of load distribution. The pipe comes in standard 20' or less standard nominal laying lengths and carries the standard Fastite Joint pressure ratings. During installation, Fastite Joint Push-Bar Pipe is jacked or pushed with the spigots ahead. This allows for any debris remaining from the pipe bursting or pipe jacking operation to flow smoothly over the bell of the Fastite Joint.

Flex-Ring joint pipe is covered on the Flex-Ring Joint page. See this page for allowable pulling loads and a picture of the Flex-Ring pulling bell assembly.

Cement-mortar lining per ANSI/AWWA C104/A21.4 and asphalt exterior coating per ANSI/AWWA C151/A21.51 are standard for Flex-Ring, MT^TM Push Pipe, GS® Push Pipe, and Push-Bar Pipe. Other linings and coatings are available for specific service conditions.

ADIP Table No. 7-21

Notes:
* Pressure rating designated is maximum water working pressure.
** Nominal wall thicknesses are Special Thickness Class 55.
*** See AMERICAN GS® Push Pipe for Gravity Sewer applications.
+ Installation and material economy are normally optimized with standard nominal length pipe. Shorter lengths are available for special requirements. Check AMERICAN.
++ Standard O-Ring gaskets are SBR rubber. Contact AMERICAN for special rubber requirements.
Coupling is manufactured of ASTM 743 Stainless Steel and is epoxy coated.

1. Engage and secure the first pipe section or the push pipe tool into the MTBM (Microtunnel Boring Machine) or expansion head per the recommendation of the equipment manufacturer. Secure the first pipe section or head as necessary to resist the push pipe connector assembly load. NOTE: For this and all remaining assembly instructions to follow, all joints must be fully assembled before pipe string is advanced into the bore.

2. Thoroughly clean the bell counterbore of the other end of the first pipe section and lubricate with American Underwater Joint Lubricant.

3. Lubricate the pushing tool with American Underwater Joint Lubricant.

4. Advance the pushing tool fully into the pipe counterbore. Jacking or assembly load should never be applied directly to the pipe ends without pushing tool properly assembled.

5. Remove any pipe-securing devices (installed in step 1 above); jack the first pipe forward one pipe length, and then remove the pushing tool.

6. Fully lubricate four (4) O-Ring gaskets with American Underwater Joint Lubricant and place in the grooves of the push pipe connector.

7. Insert a push pipe connector into the bell counterbore of the last pipe pushed, with the first O-Ring against the pipe end.

8. Lower the next MT^TM Push Pipe section into the insertion pit.

9. Clean and lubricate both the bell counterbores of the pipe.

10. In substantially straight alignment, assemble the bell onto the connector and pushing tool, securing the leading pipe as necessary (until assembly load is at least balanced by the jacking force required to propel the pipe string).

11. Jack the pipe forward one pipe length, and then remove the pushing tool.

12. Repeat steps 6-11 described above as necessary until line segment is installed.

ADIP Table No. 7-22

Notes:
* Installation and material economy are normally optimized with standard nominal laying length pipe. Shorter lengths are available for special requirements. Check AMERICAN.
** Nominal wall thicknesses are Special Thickness Class 56.
+ Standard O-Ring gaskets are NBR rubber. Contact AMERICAN for special rubber requirements.

1. Engage and secure the plain end (no counterbore) of the first pipe section or the push pipe tool into the MTBM (Microtunnel Boring Machine) or expansion head per the recommendation of the equipment manufacturer. Secure the first pipe section or head as necessary to resist push pipe connector assembly load. NOTE: For this and all remaining assembly instructions to follow, all joints must be fully assembled before pipe string is advanced into the bore.

2. Thoroughly clean the bell counterbore of the first pipe section.

3. Lubricate the 6"-long pushing tool with American Underwater Joint Lubricant and install into the bell of the first pipe section. Jacking or assembly load should never be applied directly to the pipe ends without the pushing tool properly assembled.

4. Remove any pipe-securing devices (installed in step 1 above), jack the first pipe forward one pipe length, and then remove pushing tool.

5. Lower the next GS® Push Pipe section into the insertion pit.

6. Clean both the bell counterbore of the pipe just advanced and the machined spigot of the next pipe section, especially the (2) O-Ring grooves on the spigot.

7. Fully lubricate (2) O-Ring gaskets with American Underwater Joint Lubricant and install in the spigot grooves. Then apply a liberal amount of joint lubricant to the exposed bell counterbore and the spigot of the next pipe section.

8. In substantially straight alignment, assemble the spigot end fully into the exposed bell, securing leading pipe as necessary (until assembly load is at least balanced by the jacking force required to propel the pipe string).

9. Repeat steps 2-8 described above as necessary until line segment is installed.