JWC (Jeong Woo Coupling) pipe couplings are a staple in Singapore’s marine, shipyard, oil and gas, and water infrastructure sectors. Manufactured in South Korea under the MP Joint brand, JWC couplings use a
stainless steel casing with a rubber sealing sleeve — no welding, no flanges, no special tools.
David Phee Enterprise is the exclusive Singapore distributor for JWC couplings, supplying ship chandlers, shipyards, and industrial contractors across Singapore, Malaysia, and Indonesia.
Why Engineers Specify JWC
JWC couplings are engineered for three things: fast installation, reliable sealing, and long service life.
- Stainless steel casing — SUS 304 or SUS 316, corrosion-resistant
- Grip rings — SUS 301H, bites into the pipe surface to resist pull-out
- Rubber sleeve options — EPDM, NBR, Silicone, or FKM/Viton depending on media
- No pipe edge processing — cuts installation time significantly
- Size range — 15A to 600A depending on model
The Three Main JWC Series
MJS — Flexible Type (15A–600A)
The MJS is JWC’s core flexible coupling. It connects two pipe ends while absorbing movement — vibration, bending up to 2–5°, thermal expansion, and impact.
Key specs:
- Working pressure (marine): 4.2–16 bar | Industrial: 8.4–32 bar (size-dependent)
- Axial movement: 5mm (15A–150A), 10mm (175A–500A), 15mm (550A+)
- Noise reduction: over 60% compared to welded connections Use MJS where pipes experience vibration or movement — engine rooms, pump lines, and long industrial pipe runs. For higher pressure applications, specify the MJSF (Flexible Force Type). An upgraded version, the MJSG (Flex-Grip Type), adds a grip ring on one side for installations where pipe pull-out is also a concern.
MJG — Grip Ring Type (15A–350A)
The MJG is JWC’s grip ring coupling — a patented design that replaces welding, flanges, unions, and groove joints in a single product.
Key specs:
- Working pressure (marine): 7–16 bar | Industrial: 14–32 bar
- Angular deflection: 5° (15A–50A), 4° (65A–175A), 2° (200A+)
- Gap setting: 0–8mm (15A–65A), 0–15mm (80A+)
- No pipe end preparation required Use MJG where a permanent, pull-out resistant connection is needed without welding. Common in shipyard piping, industrial plant installations, and water infrastructure projects. For higher pressure, specify
the MJGF (Grip Force Type).
MJH — Hinge Repair Clamp (15A–600A)
The MJH is a single-lock hinge repair clamp designed for in-situ pipe repair. Its open-and-close hinge design lets you fit it around an existing pipe without dismantling the line.
Key specs:
- Working pressure (marine): 4.2–16 bar | Industrial: 8.4–32 bar
- Hinge (single lock) design — clamps directly over damaged section
- For sizes over 350A: double/triple/four-lock long clamp versions available
- For higher pressure: MJDF (Repair Force Type) Use MJH when a pipe is leaking and you need a fast, non-invasive fix. Widely used by ship chandlers supplying emergency repair stock to vessels. For damaged elbows and welded sections, the MJER (Elbow Repair Clamp) covers 13A–500A with a two-part split design.
Choosing the Right JWC Coupling
MJS (Flexible Type) — New pipe installation where vibration, expansion, or movement needs to be absorbed
MJSG (Flex-Grip Type) — Same as MJS but with added grip where pipe pull-out is a risk
MJG (Grip Ring Type) — Permanent connection without welding; replaces flanges and groove joints
MJH (Hinge Repair Clamp) — Repairing a leaking straight pipe in-situ, no dismantling needed
MJER (Elbow Repair Clamp) — Repairing a leaking elbow or welded section
Ordering Information
When requesting a quote, provide:
- Pipe outer diameter (OD) in mm or inches
- Pipe schedule (SCH 40, SCH 80, etc.)
- Working pressure in bar or PSI
- Media — water, seawater, oil, gas, or other
- Rubber type — NBR (default), EPDM, Silicone, or Viton
Get a Quote
David Phee Enterprise stocks JWC couplings for same-day delivery in Singapore, with regional fulfilment for Malaysia and Indonesia.
Visit https://www.davidphee.com to request a quotation.