1. Gabatarwa

ASTM A333 Gr.6wani abu ne da ake amfani da shi sosai a bututun ƙarfe mai ƙarancin zafi, tare da ƙaramin zafin aiki na -45°C. Saboda kyawun ƙarfinsa na ƙarancin zafi da kuma ingancinsa, ana amfani da shi sosai a masana'antun man fetur, kayan aikin cryogenic, da tsarin watsa iskar gas mai ruwa-ruwa.

A fannin siyan injiniya,Bututun A333 Gr.6Sau da yawa ana rarraba su zuwa yanayi biyu na wadata: "Sabis Mai Daɗi" da "Sabis Mai Daɗi" (daidaitacce/na yau da kullun). Duk da cewa nau'ikan biyu sun cika buƙatun sinadaran asali da ƙa'idodin kayan aikin injiniya na ma'aunin ASTM A333, sun bambanta sosai a cikin juriyarsu ga tsatsa ta hydrogen sulfide (H₂S) - wani bambanci wanda ke ƙayyade yanayin aikace-aikacen su daban-daban.

2. Babban Bambanci Tsakanin Sabis Mai Tsami da Mai Zaki

2.1 Sharuɗɗan Sabis

Sabis Mai Daɗi (Ba ya da tsami): Ya dace da muhalli ba tare da H₂S ko kuma tare da ƙarancin matsin lamba na H₂S. Babban abin da za a yi la'akari da shi a cikin ƙira shine tauri mai ƙarancin zafi da ƙarfin ɗaukar matsi na al'ada.

Sabis na Tsami: An tsara shi musamman don muhallin da ke ɗauke da H₂S mai danshi, inda kayan dole ne su jure yanayin zafi mai ƙarancin zafi da tsatsa a lokaci guda. Kayan aikin gyaran tsami kuma ana iya amfani da su sosai don amfani da kayan aikin gyaran zaki.

2.2 Kula da Haɗakar Sinadarai

Duk da cewa ƙa'idodin ASTM A333 Gr.6 na asali sun kafa iyaka ga C, Mn, P, S, da sauran abubuwa, bututun sabis na tsami suna buƙatar sarrafa sinadarai masu tsauri sosai:

Sigogi	Daidaitaccen A333 Gr.6	Sabis mai tsami A333 Gr.6
Sulfur (S)	≤ 0.035%	Ana sarrafa shi sosai, yawanci ≤ 0.015%
Phosphorus (P)	≤ 0.035%	Ana sarrafa shi sosai, yawanci ≤ 0.025%
Daidaiton Carbon (CE)	Ba dole ba ne	An iyakance shi sosai (misali, ≤ 0.43%) don hana tauri mai yawa

Ta hanyar ƙara rage ƙazanta kamar S da P, da kuma iyakance daidai da carbon, bututun mai amfani da tsami yana rage saurin kamuwa da tsagewar sulfide stress corrosion crashing (SSC) daga mahangar sinadaran sinadarai.

2.3 Bukatun Tauri da Maganin Zafi

Kula da tauri yana ɗaya daga cikin mahimman abubuwan da ke bambanta tsakanin sabis mai tsami da mai zaki. Sabis mai tsami A333 Gr.6 yana buƙatar matsakaicin tauri na 22 HRC (Rockwell C) ko 248 HBW. Wannan saboda ƙananan tsarin suna da saurin kamuwa da tsatsa da hydrogen ke haifarwa da kuma tsatsa a cikin muhallin H₂S.

Dangane da maganin zafi, bututun mai tsami yawanci suna buƙatar hanyoyin da aka tsara ko aka daidaita ko aka daidaita da kuma aka daidaita (Q&T) don cimma tsari iri ɗaya, mai tsari mai kyau wanda ke haɓaka juriyar SSC. Bututun sabis na yau da kullun (mai daɗi) suna da buƙatun maganin zafi mai sauƙi.

2.4 Ƙarin Bukatun Gwaji

Dole ne a tabbatar da bin ƙa'idodin NACE (misali, NACE MR0175 / ISO 15156), wanda yawanci ya haɗa da:

Gwajin SSC (Fashewar Damuwar Sulfide, NACE TM0177)

Gwajin HIC (Fashewar da Hydrogen ya haifar, NACE TM0284)

Bututun sabis na yau da kullun (mai daɗi) gabaɗaya suna buƙatar biyan buƙatun gwajin tasirin zafi mai ƙarancin zafi na ASTM A333 (-46°C, matsakaicin matsakaicin kuzarin tasiri ≥ 20J) tare da tabbatar da haƙƙin injina na yau da kullun.

3. Takaitawa da Shawarwari kan Zaɓe

Bangare	Daidaitaccen A333 Gr.6	Sabis mai tsami A333 Gr.6
Matsakaici na Sabis	Babu H₂S ko H₂S mara kyau	Maganin tsami mai ɗauke da ruwan H₂S
Iyakar Tauri	Babu ƙuntatawa ta musamman	≤ 22 HRC / 248 HBW
Maganin Zafi	Tsarin aiki na al'ada	Tsarin tsari iri ɗaya ko na al'ada; tsari iri ɗaya
Ƙarin Gwaji	Gwajin tasirin ƙananan zafin jiki	Gwajin SSC + HIC bisa ga ƙa'idodin NACE
Bin Dokokin NACE	Ba a buƙata ba	Mai jituwa da NACE MR0175

Shawarwari Kan Zaɓi: A lokacin ƙira, yana da mahimmanci a tantance ko H₂S yana nan a cikin yanayin sabis. Idan akwai yanayin H₂S mai danshi, ƙayyadaddun sayayya dole ne ya bayyana a sarari "A333 Gr.6 don Sabis Mai Daɗi, wanda ya dace da NACE MR0175 / ISO 15156," tare da takamaiman buƙatu don tauri, daidai da carbon, maganin zafi, da ƙarin gwaji. Bai kamata a taɓa amfani da bututun A333 Gr.6 na yau da kullun a cikin maganin tsami ba, saboda wannan na iya haifar da gazawar fashewar tsatsa mai tsanani.