Riken Keiki 351A Extension Hose Pipe (20M)

Riken Keiki Extension Hose Pipe (20 Meters) — P/N: 351A

The Riken Keiki Extension Hose Pipe (P/N: 351A) is a 20-meter heavy-duty, anti-static, hydrocarbon-resistant gas sampling hose engineered specifically for pre-entry testing in marine ballast tanks, cargo holds, pump rooms, and industrial confined spaces. Manufactured by Riken Keiki Co., Ltd., this precision accessory enables suction-type portable gas monitors and motorized external sampling pumps to draw gas samples over extended distances without altering sample composition or causing measurement lag.

Formulated with a fluoro-polymer/polyurethane composite inner liner and a reinforced outer jacket, the P/N 351A hose prevents target gas absorption while delivering structural crush resistance under severe deck operations. Integrated brass/stainless-steel quick-connect couplings ensure hermetic seal integrity, preventing false oxygen readings or atmospheric dilution during critical Solas Chapter VI/VII pre-entry clearance procedures.

Model Details

• Manufacturer: Riken Keiki Co., Ltd. (Japan)
• Manufacturer Part Number (MPN): 351A
• Model Designation: Extension Hose Pipe 20M (P/N 351A)
• Hose Standard Length: 20.0 Meters (65.6 Feet)
• Internal Diameter (ID): 4.0 mm
• Outer Diameter (OD): 6.0 mm
• Coupling Type: Quick-Connect Bayonet / Push-Lock Male-Female Fitting with Viton O-Ring Seal

Technical Specifications: Extension Hose Pipe 351A

Equipment Compatibility

• The Riken Keiki 351A 20-Meter Extension Hose is engineered to integrate seamlessly with the following portable instruments and suction attachments:
• Portable Multi-Gas Detectors: Riken Keiki / RKI GX-2009, GX-2012, GX-3R, GX-3R Pro, GX-6000, GX-8000, EAGLE, EAGLE 2, and RX-515 / RX-8000 series.
• External Suction Pumps: RP-3R, RP-3R Pro, RP-2009, RP-6, and hand-aspirated bulb draw assemblies.
• Sampling Probes: Standard rubber sampling nipples, weighted deep-tank probes, probe handles with water-trap filters, and telescopic stainless steel probes.

Marine & Industrial Applications

1. Shipboard Pre-Entry Checks: Remote sampling of enclosed spaces such as cargo holds, ballast tanks, void spaces, fuel tanks, and chain lockers in compliance with SOLAS Regulation XI-1/7 and IMO MSC.1/Circ.1477.
2. Offshore Rig & FPSO Inspections: Gas draw monitoring in moonpools, pontoon legs, riser balconies, and production module void spaces.
3. Petrochemical Tank Farms: Vapor-space testing in floating-roof tanks, underground storage vessels, and chemical process piping.
4. Municipal Infrastructure & Utilities: Safe atmospheric testing in manholes, sewer interceptors, storm drains, and wastewater digester domes.
5. Refinery Turnarounds: Multi-gas pre-entry screening for boilers, cracking units, and distillation columns.

Marine Superintendent Field Tips:

• Perform a Leak Test Before Entry: Always perform a vacuum drop check prior to lowering the line. Attach the 20M 351A hose to the pump, turn the pump on, and block the far end tip with your finger. The pump should trigger a low-flow fault alarm within 3–5 seconds. If the pump continues running smoothly, you have a leak in the hose coupling or O-ring seal, which will dilute your tank sample with ambient air!
• Prevent Liquid Ingestion: When sampling bilge wells, lower cargo holds, or ballast tanks, always fit a hydrophobic water-stop filter disk and a weighted probe tip to the far end of the 351A hose. Sucking water or condensation into a 20m line requires full flushing and drying before the hose can be re-used for accurate readings.
• Purge After Toxic/Hydrocarbon Sampling: After testing spaces with high concentration hydrocarbon vapors or elevated allow the pump to run with the 351A hose exposed to clean ambient air for at least 3 minutes to flush out residual vapor outgassing from the inner walls.
• Coiling and Storage Care: Never tightly bend or pinch the 351A hose when stowing. Reel the hose in figure-8 or wide-loop loops (>30 cm diameter) to prevent long-term memory setting or crimping of internal reinforcement.

Frequently Asked Questions

What is the primary function of the Riken Keiki P/N: 351A hose?

The Riken Keiki 351A is a 20-meter extension sampling hose designed to draw air samples from remote, hard-to-reach, or confined spaces back to a portable gas detector or sample pump for pre-entry safety testing.

Will using a 20-meter extension hose delay my gas detector readings?

Yes, using a 20-meter sampling hose introduces a sample transport delay time. As a general rule, allow 2 to 3 seconds of sampling time per meter of hose (minimum 45–60 seconds for a 20m hose) in addition to the sensor’s response time before taking a final safety reading.

Is the Riken Keiki 351A extension hose chemical resistant?

Yes, the 351A hose is manufactured using non-reactive synthetic materials designed to resist common marine fuels, oils, industrial solvents, and light chemical vapors while minimizing gas absorption along the inner wall.

Can I use the 351A hose with hand-aspirated pump bulbs?

While the 351A hose can be connected to hand aspirator bulbs, a motor-driven motorized sample pump (such as the RKI RP-3R or RP-6) is strongly recommended for a 20-meter line length to ensure continuous, reliable sample velocity.

How do I check if my 351A 20-meter extension hose has a leak?

Connect the hose to your gas monitor’s sample pump, power on the device, and seal the far end of the hose tightly with your thumb. If the pump indicates a “Flow Fault” or low-flow alarm, the hose system is airtight. If the pump keeps running normally, check all hose connections and fittings for leaks.