Support, Process & Refining Tube

At Steloy Foundries, centrifugally cast tubes such as catalyst, cracking and reformer tubes are manufactured in accordance with the general requirements of ASTM A608 for high-temperature and high-pressure applications. Selected alloys from DIN EN10295 and a number of unassigned / proprietary alloys are also used.

Tubes are supplied as-cast, partially machined or fully machined. Machining of outer tube surfaces involves turning while inner surfaces are pull bored. Support tubes or “stanchions” are normally cast, while weld preps are machined and Tig welded together on in-house automatic and semi-automatic orbital and rotating welding machines. The supports usually have holes for the supporting bars or pins – these are either drilled or plasma cut on Steloy’s in-house machining and plasma cutting equipment.

The current Steloy range offers sizes up to 830mm in diameter and 5,500mm long. Smaller diameter tubes can be longer, i.e. 4,500mm long, with outer diameters ranging from 80mm to 200mm, and inner diameters as small as 32mm. The surface finish after pull boring is typically 1.6 to 3.2m. The variation in dimensions is within the tolerances indicated in section 8 of ASTM A608 and complies with the requirements of ASTM A530.

Product marking, certification and pressure testing has been conducted in accordance with mutually agreed procedures. Provisions have been made to conform to supplementary requirements of ASTM A608 through various analysis, testing and examination procedures.

Centrifugally cast tubes are produced in accordance with the general requirements of ASTM A608. Selected alloys from DIN EN 10295 and a number of unassigned/proprietary alloys are also produced.

Specification of Reference

Alloy

Remarks

ASTM A608

HC30; HD50; HE35; HF30; HH 30; HH33; HI35; HK40; HK30; HL30; HL40; HN40; HT50; HU50; HW50; HX50

 

API 560

ASTM A608 HK40

 

Unassigned

HP45; HP45 Nb; HP45 Nb micro

25Cr35Ni Nb MA

35Cr 45Ni Nb MA

Modifications of 1.4852

Micro alloyed Ti, Zr, RE

DIN EN10295

G X 40 Ni Cr Si Nb 35-26

G X 40 Ni Cr Nb 45-35

G Ni Cr 28W

G X 50 Ni Cr CoW35-25-15-5

1.4852

1.4889

2.4879

1.4869