46 CFR § 154.524 - Piping joints: Welded and screwed couplings.

---
identifier: "/us/cfr/t46/s154.524"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "46 CFR § 154.524 - Piping joints: Welded and screwed couplings."
title_number: 46
title_name: "Shipping"
section_number: "154.524"
section_name: "Piping joints: Welded and screwed couplings."
chapter_name: "COAST GUARD, DEPARTMENT OF HOMELAND SECURITY"
subchapter_number: "O"
subchapter_name: "CERTAIN BULK DANGEROUS CARGOES"
part_number: "154"
part_name: "SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "46 U.S.C. 3703, 9101; Department of Homeland Security Delegation No. 0170.1."
regulatory_source: "CGD 74-289, 44 FR 26009, May 3, 1979, unless otherwise noted."
cfr_part: "154"
---


# 154.524 Piping joints: Welded and screwed couplings.

Pipe lengths without flanges must be joined by one of the following:

(a) A butt welded joint with complete penetration at the weld root except that for design temperatures colder than −10 °C (14 °F) the butt weld must be double welded or must be welded using:

(1) A backing ring that for design pressures greater than 979 kPa gauge (142 psig) must be removed after the weld is completed;

(2) A consumable insert; or

(3) An inert gas back-up on the first weld pass.

(b) A slip-on welded joint with sleeves and attachment welds is allowed for an open ended pipe with an external diameter of 50 mm (2 in.) or less and a design temperature of −55 °C (−67 °F), or warmer.

(c) A socket weld fitting with attachment welds is allowed for pipe with an external diameter of 50 mm (2 in.) or less and a design temperature of −55 °C (−67 °F) or warmer.

(d) Screwed couplings are allowed for instrumentation and control piping that meets § 56.30-20 and § 56.50-105 (a)(4) and (b)(4) of this chapter.

(e) A method or fitting specially approved by the Commandant (CG-ENG).

[CGD 74-289, 44 FR 26009, May 3, 1979, as amended by CGD 82-063b, 48 FR 4782, Feb. 3, 1983]