SPECIFICATION FOR 7" HINGED NON-WELDED POSITIVE BOW CENTRALIZER WITH END
COLLARS 7” X 9-5/8” - ONGC EDP No. - 060034146
1.0 SCOPE & APPLICATION:
The specification covers minimum performance requirements and guidelines for procurement of 7"
hinged non-welded positive bow centralizer with end collars. Positive centralizers are used where the
annulus is made by overlap of 7” casings with 9-5/8” casing for centralization.
2.0 GENERAL FEATURES:
2.1 Manufacturer shall be registration under API Spec Q1, 9th Edition, and/or ISO 9001:2015.
2.2 Centralizers shall be new & recent manufactured (not older than one year on the date of shipment
/ inspection whichever is later).
2.3 Manufacturer / Vendor shall have registration under API Spec Q1, 9th Edition, and/or ISO
9001:2015 and should be valid as on the date of tender opening and till the completion of the supply.
2.4 All design, testing / inspection, material and other technical details shall be in strict accordance
with latest API 10D standards.
2.5 Bidder should submit detailed drawing of the item / items including dimensions for technical
scrutiny. The drawing of successful bidder will be approved by the indenter at the time of placement
of the purchase order.
2.6 Bidder shall provide steel nails two times the actual requirement.
3.0 TECHNICAL FEATURES OF MATERIAL:
3.1. Codes & Standards
Sl. No.
1
Standards Title
API 10D
Specification for Bow-String, Non-Welded Casing Centralizers with End Collars.
API has advised not to impose API monogram on Bow Spring casing
Centralizer.
3.2 Constructional Features: 3.2.1 Positive centralizers shall consist of Bow Strings and End Collars.
3.2.2 Bow Strings: 3.2.2.1 Bow Strings shall be made from ‘High Quality Spring Steel’, processed in one piece and formed
by sequential heat treatment resulting in a high strength and flexible bow.
3.2.2.2 Bow Strings shall have a Straight Bow Profile.
3.2.3 End Collars: 3.2.3.1 End Collars shall be formed in two identical and interchangeable sections that are hinged and
able to latch one another to ensure ease of assembling and installation of the interchangeable units.
The hinges shall be folded to the inside to minimize the collar stretch that tends to occur when
centralizers encounter tapers common to some pipe connections.
3.2.3.2 End Collars shall be made from ‘High Strength Steel’ and a ‘Reinforcing Rib’ shall be stamped
into the End Collar to strengthen it and to ensure maintenance of its round configuration during
transport.
3.2.3.3 Positive centralizer shall have interlocking adjoinment between the End Collar and the Bow
Spring to make a Strong Singular Unit.
3.3 Functional Parameters: 3.3.1 The construction of Centralizer shall assure that hinges will not open while casing is being run
regardless of hole direction or irregularities in formation.
3.3.2 The Centralizer shall be designed as per API 10 D specifications.
3.3.3 The Centralizer shall provide maximum effective centralizing of casing with minimum obstruction
to flow in annulus between casing and borehole.
3.3.4 The Centralizer shall be installed very conveniently and quickly on the casing pipe by merely
wrapping the pre-assembled two halves on the pipe and inserting ‘High Strength Steel Locking Pin’ in
the collar hinges.
3.3.5 The centralizer shall be shipped in half assembled condition for ease in shipping and storage
cost.
3.3.6 Material / Metallurgy of Centralizers shall be such that the Mechanical Properties of Centralizers
do not change at Max. Bottom Hole Temperature up to 400° F.
3.3.8 Bow-string Casing Centralizers complete as per the table given below.
Sl. No.
Description
7” Centralizer
1
2
Inner casing size
Outer casing size & PPF
3
Centralizer Type
4
5
6
Bow Profile
No of Bows (Min)
Minimum Length
7”
9.5/8” & 53.5 ppf
Non-Welded hinged positive
Centralizers with End Collar.
Straight Bow Profile.
6
22”
3.4 Material: Vendor to ensure that material of construction offered for different components of Bow-Spring Casing
Centralizer shall be compatible with specified operating conditions and parameters and shall be
suitable for the intended service, except as required or prohibited by the Data Sheet / Indenter or the
relevant codes and standards mentioned at 3.1. All material shall be sound, free of shrunk / blowholes,
cracks and scale-blisters.
3.5 Painting: As per manufacturer’s standard / best industrial practices to ensure durability & reliability for
protection against corrosion.
3.6 Data Sheet: All information in the data sheet shall be furnished completely by the vendor along with the BID as
per the Annexure-I enclosed.
4.0 NAME PLATE AND MARKING DETAILS:
Following information shall be die-stamped, paint-stencilled or adhesive-labelled on the collars or the
bow springs.
4.1 Casing Diameter.
4.2 Hole Diameter.
4.3 API Spec 10 D.
5.0 INSPECTION PROCEDURE:
Inspection and testing to be carried out as per API 10D and Annexure 1.
6.0 MISCELLANEOUS:
6.1 Literatures, Manuals and Drawings etc.: The Vendor / Manufacturer should furnish Literature, Manual, Drawing of the equipment/item.
6.2 Documentations: 6.2.1 Certificates that the equipment has been designed, manufactured and tested conforming to the
specification & relevant standards.
6.2.2 Documents shall provide physical identification of dissembled components of the centralizers.
6.2.2 Installation Manual should be provided along with the Centralizer.
6.2.3 Warranty Certificate.
6.3 Warranty & Guarantee: 6.3.1 The Vendor / Manufacturer shall warrant that materials used in the manufacturing of this
Equipment shall meet the requirements set in this specification and relevant standards. It shall be
new, free from defects in material, design and workmanship.
6.3.2 The Vendor / Manufacturer shall warrant that his equipment will satisfy the requirements of the
intended use as specified.
6.4 Packing: 6.4.1 All spare parts furnished by bidder should be wrapped, packed & clearly marked for easy
identification. Packing list is to be furnished.
6.4.2 Vendor shall ensure that material does not get damaged in packing during loading/unloading
and transportation/transit. Packing size to be specify by indenter.
Annexure–1
DATA SHEET OF BOW-STRING, NON-WELDED CASING CENTRALIZERS WITH
END COLLARS
(TO BE FILLED IN BY THE VENDOR/MANUFACTURER)
1. Collar Inside diameter (inches):
2. Codes & Standards followed:
3. Product Code:
4. Positive Centralizer Type:
5. Bow Profile:
6. Min ID (inches):
7. Max. O.D. (inches):
8. Compressed O.D. (inches):
9. No. of Bows:
10. Average Length (inches):
11. Registration under API Spec Q1, 9th Edition, and/or ISO 9001:2015: Yes / No
12. List of Documentation Provided:
SIGNATURE/ELECTRONICALLY UPLOADED
Signature of the supplier / vendor / firm )