NOTICE: A price increase will be effective on January 1, 2023. See Price page for information.

Need Help? (877) RELTEKiT



The Sealing Compoundencapsulates the electrical splices, provides a strain relief for the conductors, acts as a water block, eliminates air voids which tend to act as pumps to draw in water during pressure cycles, and prevents damage from hydro-pressure.


The Inner and Outer Sealing Tubes form chemical (cohesive) bonds to the cable jacket, as well as to each other and to the Sealing Compound, providing redundancy in sealing, and mechanical integrity to the splice.The bonds are stronger than the substrates.


The Inner and Outer Sealing Tubes are of different compounds which, provides greater environmental resistance from chemicals, thermal shock, and stress cracking.


Reliability of completed splice: triple redundancy is built into sealing design; the two Seal Tubes and the Sealing Compound. All seals have been tested independently in Accelerated Life Tests for long term life in the deep-sea.


The Outer Seal is highly abrasion resistant and provides mechanical stiffness to the splice in order to better match the cable stiffness.


The chemically bonded Seals are attained by use of the BONDiT™ C-21 that activates the reaction between materials when heat is applied by a hot air gun.


Simplicity of assembly: all components are precut and prepped. The Sealing Tubes are pre-shaped and the inner walls are pre-treated. The technician need only wash the tubes and prime them with BONDiT™ C-21. Sealing is accomplished with the simple technologyof a hot airGun (or torch in an emergency.)


Tolerance to error in assembly: under test, abrading instructions were not followed, and sealing surfaces were not cleaned, but rather, deliberately contaminated. Testing demonstrated acceptable water proof seals were still obtained. Cleanliness is emphasized as a normal good operating procedure for best results.


Fast assembly time measured in minutes. No long hours of waiting for curing cycles. Ease of transport and storage; one year shelf life. Simple skill, low cost,permanent field or production splicing.


Wide range of sizes and applications. Custom designs available on request, for all underwater and down hole oil well applications. Both hot splice and cold splice technology available.




The purpose of this document is to aid the user in making a permanent, pressure and water proof splice in polyethylene jacketed cable, using the supplied splice kit.







Refer to the Material Safety Data Sheet for safety precautions of BONDiT™ C-21. Nylon or rubber gloves and safety glasses are recommended.







BONDiT™ C-21:        1 year minimum, when stored at 70°F, sealed in original container.


Splice Seal Compound:  2 year minimum, when stored at 70°F, sealed in original container.


All other kit components: 5 years when stored at 70°F.





Tooling and Materials List


Following is a list of required tools and materials, not included in the kit:


Electrical butt crimps and insulators/shrink tubing

Wire insulation strippers

Long, thin flathead screwdriver or probe, 8+ inches

Razor knife

Needle nose pliers, 6 inch

MethylEthylKetone, 5 Ounce (MEK)

Box Kimwipes or equivalent

Disposal container (Kimwipes)

6" steel scale

Nylon or rubber gloves

Safety glasses


Included in the splice kit:


2  Splice Seal Compound, strips (red)

1  Inner Seal Tube, 7" X 3/4" O.D. (green)

1  Outer Seal Tube, 9.5" X 3/4" O.D. (black)

BONDiT™ C-21 in dispenser

1  Abrasive Pad, 1 1/2" x 9"




Cable Preparation


The cable must be inspected for damage, stripped and the outer jacket evenly abraded.


Inspect the cable jackets for significant damage in splice area. Small nicks can quickly be removed with the provided Abrasive Pad by abrading the damaged area. If light abrading does not smooth out the damage, an Exacto knife (or razor blade) can be used to scrape the area with the blade, back and forth, along the length of the cable until all nicks, cuts etc. are removed.


CAUTION: Using excessive pressure with the blade, could result in further damage to the cable. Cable with significant damage should be cut back to good jacket material.


Strip the ends of both cables to be spliced, to expose 2 1/4" of the insulated shield/conductors. When stripping the jacket from the conductors, avoid damaging the conductors and their shields.


Cut the conductor lengths so that the wire butt crimps will be staggered in the completed assembly. This will minimize the finished splice diameter.


Strip insulation from conductors using wire strippers to match butt crimps. Be careful not to nick conductors or remaining insulation.


To achieve a best bond between the cable jacket and the Splice Seal Tubing, it is necessary to abrade the surface of the jacket with the Abrasive Pad provided.


Wrap the pad around the jacket and abrade with a twisting motion a 3" minimum length, starting from the end of the jacket. The jacket will have a dull, matt finish when properly abraded. If the jacket is glossy and/or smooth in appearance, it is not properly abraded and may produce a poorer bond.







Scrub the cable jacket with TCE or MEK for two foot on either side of the splice to ensure cleanliness when the Inner and Outer Seal Tubes are assembled on the cable.


Before completing the conductor splices, the Inner and Outer Seal Tubes must be placed over the cables and moved out of the way (1-2 feet). The inside of the Sealing Tubes must be cleaned, and coated with BONDiT™ C-21 before assembly on the cable.




Inner and Outer Seal Preparation


With both the Inner Seal Tube, (green) and Outer Seal Tube, (black), wad one or two Kimwipes into a ball and grip with needle nose pliers. Dip ball into TCE or MEK, (w/ clean pliers), insert into the Sealing Tubes and scrub the length of the interior walls. Use a long screw driver to reach deeper into the tubing for scrubbing.


Repeat this step 2 times for both Sealing Tubes. Use fresh Kimwipes each time. NEVER immerse the same wipe in the MEK twice, or the cleaning agent may become contaminated.


BONDiT™ C-21 is shipped pre-mixed and ready for application. Vigorously shake the dispenser for several seconds before applying it to the prepared cable jackets. When not in use, keep the dispenser closed. Avoid continuous heat exposure, such as, from direct sunlight.


CAUTION: Wear protective rubber gloves.


Partially saturate a Kimwipe with BONDiT™ C-21 and swab the entire inside surfaces of both of Seal Tubes.


Slide the Outer Seal Tube onto the cable, followed by the Inner Seal Tube, far enough to be out of the way (about 1-2 feet.)





Coating the Cable


CAUTION: Wear protective nylon, or rubber gloves.


Before applying BONDiT™ C-21, the cable jacket should be free of contaminants. Scrub cable with TCE or MEK saturated Kimwipes. Use fresh Kimwipes for every scrub. Continue to clean abraded area until Kimwipes appear clean after scrubbing. It is important that all abraded areas of the cable jacket are cleaned properly to insure a quality seal.


Do not contaminate cleaned areas with bare hands. Handle with clean gloves.

Partially saturate a Kimwipe with BONDiT™ C-21 and swab onto abraded area of cable. Liquid should readily permeate and saturate (wet) the entire abraded surface of the cable.


CAUTION: If the BONDiT™ C-21 does not readily spread (wet) the surface, and tends to significantly pool/puddle/bead, the cable is not adequately cleaned and/or abraded. In such a case, clean the jacket again and apply BONDiT™ C-21. Adequate BONDiT™ C-21 is supplied for repeating the entire procedure several times.


Coat Sealing Compound surface with the BONDiT™ C-21.


Once the jacket is coated, no drying time is required agent. Up to four hours exposure at ambient is acceptable.




Final Assembly


The Inner and Outer Seals will now be positioned over the splice and heat shrunk to form water tight seals.


Center the Inner Seal Tubing over splice area so that approximately 1 1/4", on either side, covers the coated jacket.


Shrink the Inner Seal Tubing onto splice with heat gun. Heat must be applied evenly, starting in the center, until the entire length has shrunk down around the cable and splice.


After tubing has shrunk, apply heat evenly to the 1 1/4" long cable seal areas, approximately 1½ minutes. BONDiT™ Agent C-21 and Inner Seal Tube should reach a high enough temperature (approximately 500°F to react and form a water-proof bond. The strength of bond will be somewhat dependent on the type of jacket material: polyethylene forming highly cohesive bonds, and rubbers forming weaker adhesive bonds.


CAUTION: Excessive heat may damage cable jacket.


Allow the splice assembly to cool for ease of handling, and thoroughly wash the assembly with TCE or MEK.


Saturate a Kimwipe with BONDiT™ C-21 and swap the entire assembly and remaining abraded cable. Liquid should readily permeate and wet the surface of the cable. Center the Outer Seal Tubing over the Inner Seal Tube so 1 1/4" extends past the Inner Seal Tube beneath it on either side. Shrink the Outer Seal Tube using the same heating procedure as for the Inner Seal Tube. This seal will provide an additional water tight seal and mechanical abrasion protection.


Re-inspect cable for any damage. Splice is complete.





Technical Support


For technical support call RELTEK at 707-284-8808, or email



Reference RELTEK Document No. A400-0001 Rev C