ASTM A27 Grade 70-36 Cast Steel Flanged Head | Types 22, 29 and 33 Marine

Product Specification

ASTM A27 Grade 70-36 Cast Steel Flanged Head | Types 22, 29 and 33 Marine Outfitting

Product Overview

The ASTM A27/A27M Grade 70-36 cast steel flanged head is a marine outfitting component supplied in Types 22, 29, and 33 according to the customer’s drawing and dimensional requirement. The cast profile provides an integral head and flange geometry for incorporation into a shipboard steel assembly where controlled dimensions, heat-treated mechanical properties, surface condition, and inspection traceability are important procurement requirements.

The supplied data do not identify the complete parent assembly, pressure rating, service load, or installation method. For this reason, the flanged head should be ordered as a drawing-controlled component rather than treated as a complete pressure-vessel head, lifting fitting, or load-rated mooring product. A plate-formed mild-steel flanged or flanged-and-dished head can also be discussed, but it is a different manufacturing route and is not automatically interchangeable with the cast steel version.

Quick Specifications

• Product form: Cast steel flanged head → supplied as a drawing-controlled marine outfitting component for integration into a larger steel assembly.
• Standard material designation: ASTM A27/A27M Grade 70-36 [485-250] → a heat-treated and mechanically tested carbon steel casting grade.
• Available types: 22 / 29 / 33 → each type has a different flange diameter, section dimensions, profile depth, and calculated weight.
• Dimensional system: Inch dimensions with pound weights → metric conversion should be used only as a reference unless the approved drawing is issued in SI units.
• Heat treatment: Full annealing, normalizing, normalizing and tempering, or quenching and tempering as permitted by ASTM A27/A27M → actual route to be stated in the material documentation.
• Quality control: Chemical analysis, tensile testing, dimensional inspection, heat-treatment records, and visual inspection → inspection scope follows the purchase specification.
• NDT option: Magnetic particle testing for ferromagnetic cast steel → detects surface and near-surface indications; acceptance criteria and examination areas must be specified.
• Surface preparation: Abrasive blasting, typically to Sa 2.5 when requested → primer, final coating, machining allowance, and protected surfaces are to be confirmed.

Main Technical Parameters

Selection & Inquiry Guide

Step 1: Confirm Type 22, 29, or 33 and provide the controlled drawing showing the meaning of dimensions A, B, C, D, and E, the flange profile, machining surfaces, and connection detail.

Step 2: Confirm whether the required product is a cast steel flanged head or a plate-formed mild-steel flanged / flanged-and-dished head. These constructions require different material, tooling, thickness, heat treatment, and inspection controls.

Step 3: Confirm ASTM A27/A27M Grade 70-36 [485-250], casting class if applicable, supplementary requirements, heat-treatment condition, and any impact-test or low-temperature requirement.

Step 4: Define dimensional tolerances, casting surface acceptance, machining allowance, weld preparation, identification marking, and whether repair welding is permitted.

Step 5: Confirm the NDT plan: visual inspection, magnetic particle testing, and any volumetric examination such as radiographic or ultrasonic testing. Examination method and acceptance criteria must be stated separately.

Step 6: Provide quantity, unit system, final application, mating-part drawing, surface treatment, certificate requirement, ABS survey or approval scope, destination, and required delivery time.

Structure

Integral cast head profile | Flanged outer edge | Drawing-controlled crown or dish geometry | Connection / weld preparation area | Optional machined surfaces | Identification and heat-number marking area

Casting, Heat Treatment & Inspection Advantages

• Integral casting can produce the required flange and head transition without a fabricated circumferential joint through the principal profile, subject to the approved drawing.
• Pattern, mould, riser, and process control are important for maintaining the flange diameter, section thickness, profile depth, and machining allowance across Types 22, 29, and 33.
• ASTM A27/A27M Grade 70-36 is specified as a heat-treated and mechanically tested casting grade; the heat-treatment cycle and mechanical test results should be traceable to the supplied heat or production lot.
• Visual inspection should evaluate surface texture and relevant casting indications against the agreed purchase criteria. Absolute statements such as “zero casting defects” should not be used.
• Magnetic particle testing is suitable for surface and near-surface discontinuities in ferromagnetic cast steel. It does not replace radiographic or ultrasonic examination where deeper internal soundness must be evaluated.
• Any weld repair, weld preparation, or welding of the head into the final assembly should follow an approved procedure compatible with the casting grade, heat treatment, section thickness, and project acceptance requirements.
• Dimensional inspection should be completed against the controlled drawing before blasting or coating, especially where flange flatness, mating diameter, profile depth, or machining stock affects assembly fit-up.

Custom Attributes

• Material Standard: ASTM A27/A27M → carbon steel castings for general application.
• Material Grade: Grade 70-36 [485-250] → nominal grade designation corresponding to 70 ksi minimum tensile strength and 36 ksi minimum yield strength.
• Types: 22 / 29 / 33 → select by the approved parent-assembly drawing, not by type number alone.
• Manufacturing Route: Cast steel → separate from mould-formed mild-steel plate heads.
• Heat Treatment: According to ASTM A27/A27M and purchase specification → actual condition should appear on the material documentation.
• NDT: Magnetic particle testing when required → examination area, technique, personnel qualification, and acceptance criteria must be agreed.
• Surface Treatment: Abrasive blasting / Sa 2.5 when specified → coating and protected machined surfaces to be confirmed.
• Certification: Mill or maker material certificate; ABS certification or survey according to project requirement → not assumed as standard supply.

How It Works

Approved assembly drawing defines the required head profile → Correct type and material are selected → Cast head is heat treated, inspected, and finished → Flanged geometry is fitted or welded to the mating structure → Completed parent assembly carries the service loads defined by its own engineering design

Applications

Marine steel assemblies | Ship outfitting fabrications | Drawing-controlled replacement components | Custom cast head and flange components | Newbuilding and repair projects requiring Types 22, 29, or 33

Certifications & Advantages

Material documentation, third-party witnessing, and classification certification can be arranged according to the purchase specification, foundry approval status, inspection plan, and survey scope. ABS approval or product certification is subject to technical review and survey requirements and should be confirmed before quotation.

Certification: CCS, NK, BV, ABS, DNV, LR, KR, IRS, RS, RINA, CRS, Makers Test Certificate.

Drawing & Photos

FAQ

Q1: What does ASTM A27/A27M Grade 70-36 [485-250] mean?

A1: It identifies a carbon steel casting grade covered by ASTM A27/A27M. The grade is heat treated and mechanically tested, with the designation indicating 70 ksi [485 MPa] minimum tensile strength and 36 ksi [250 MPa] minimum yield strength. The full order should still state the standard revision, class, supplementary requirements, and certification scope.

Q2: Does magnetic particle testing prove that the casting is free from internal defects?

A2: No. Magnetic particle testing is used for surface and near-surface discontinuities in ferromagnetic materials. If deeper internal soundness must be evaluated, the purchase specification should separately require an appropriate volumetric method and acceptance standard.

Q3: Can a cast steel flanged head be replaced directly by a formed mild-steel flanged-and-dished head?

A3: Not without engineering confirmation. The two products use different materials and manufacturing routes, and may differ in wall thickness, radii, weld detail, heat treatment, mechanical properties, tolerances, and inspection requirements. Interchangeability must be confirmed from the approved parent-assembly drawing.