2x8.4m TELESCOPE
& CENTRAL BEARING SUPPORT
Date: August 4th, 1997
Prepared and Approved by:
Gianpietro Marchiori/EIE
|
LBT PROJECT 2x8.4m TELESCOPE |
|
& CENTRAL BEARING SUPPORT | ||
Date: August 4th, 1997 Prepared and Approved by: Gianpietro Marchiori/EIE | ||
INDEX
1.0 SCOPE OF WORK
2.0 APPLICABLE DOCUMENTS
3.0 ITEM DESCRIPTION
4.0 INTERFACE DEFINITIONS
5.0 PERFORMANCE CHARACTERISTICS
6.0 RELIABILITY, MAINTAINABILITY REQUIREMENTS
7.0 ENVIRONMENTAL CONDITIONS
8.0 DESIGN AND CONSTRUCTION REQUIREMENTS
8.1 General Dimensions and Mass
8.2 Materials
8.3 Class of Welding
8.4 General Tolerances
8.5 Thermal Treatments
8.6 Tightening Torque of Bolts and Screws
8.7 Surface Treatments
8.8 Special Manufacturing Instructions
9.0 PRE-ASSEMBLY
10.0 PACKING AND TRANSPORT
11.0 ACCEPTANCE TESTS
12.0 SPARE PARTS
ANNEX A
The AZIMUTH FRAME STRUCTURE and CENTRAL BEARING SUPPORT are the elements composing the LBT Project.
The aim of the LBT (Large Binocular Telescope) Project is to realise a telescope having two mirrors of 8.4 m diameter, to be installed at Mount Graham in Arizona (ref. dwg. No. 407e001).
The AZIMUTH FRAME is the basic support structure of the telescope. It is made up of steel structure machined elements, assembled each other by means of bolts.
The supply of the AZIMUTH FRAME STRUCTURE and CENTRAL BEARING SUPPORT includes:
| TITLE | DOCUMENT |
| PIER/PIER CONSTRUCTION DRAWINGS/UPPER RING/GENERAL ASSEMBLY AZIMUTH PLATFORM STRUCTURE/FRAME STRUCTURE/GENERAL ASSEMBLY AZIMUTH PLATFORM STRUCTURE/LATERAL FRAME STRUCTURE/GENERAL ASSEMBLY AZIMUTH PLATFORM STRUCTURE/LATERAL FRAME STRUCTURE/SECT. A-A, B-B, H-H AZIMUTH PLATFORM STRUCTURE/LATERAL FRAME STRUCTURE/SECT. C-C-, D-D-, L-L- AZIMUTH PLATFORM STRUCTURE/LATERAL FRAME STRUCTURE/SECT. E-E-, F-F-, G-G AZIMUTH PLATFORM STRUCTURE/CENTRAL FRAME STRUCTURE/GENERAL ASSEMBLY AZIMUTH PLATFORM STRUCTURE/LATERAL PAD SUPPORT PIER/CONSTRUCTION DRAWINGS/UPPER RING/CENTRAL BEARING SUPPORT ASSEMBLY PIER/CONSTRUCTION DRAWINGSUPPER RING/LOWER BEARING SUPPORT PIER/CONSTRUCTION DRAWINGSUPPER RING/UPPER BEARING SUPPORT | Dwg. 421E037 Dwg. 430E007 Dwg. 430E008 Dwg. 430E009 Dwg. 430E010 Dwg. 430E011 Dwg. 430E012 Dwg. 430E013 Dwg. 421E042 Dwg. 421E043 Dwg. 421E044 |
| TITLE | DOCUMENT |
|
RING STEEL STRUCTURE/GENERAL ASSEMBLY AZIMUTH AXIAL HYDRAULIC PADS AZIMUTH CENTRAL BEARING AZIMUTH DRIVE MOTORS ENCODER SLIDER HEAD'S SUPPORTS ELEVATION RADIAL HYDRAULIC PADS ELEVATION LATERAL HYDRAULIC PADS ELEVATION DRIVE MOTORS ELEVATION SLIDER HEADS SUPPORTS ELEVATION AUXILIARY DRIVE ELEVATION STOW PIN ELEVATION END STOPS ROLL SHIELDS JACKING SYSTEMS ACCESS AND MAINTENANCE EQUIPMENTS MOUNTING DEVICE |
Dwg. 421E029 Dwg. 440A014 Dwg. 460A009 Dwg. 440A012 Dwg. 523A010 Dwg. 522A010 Dwg. 400E034 Dwg. 407E000 Dwg. 400E003/Dwg. 500E020 |
| TITLE | DOCUMENT |
| RIM GEAR WHEELS | Dwg. 401A004 |
The AZIMUTH FRAME STRUCTURE (see dwg. No. 430e007 and 421e042) is made up of the following elements:
All structures of the AZIMUTH FRAME STRUCTURE and CENTRAL BEARING SUPPORT are made up of steel plates of different thickness, cut and assembled through welding.
Each element composing the AZIMUTH FRAME shall be individually pre-machined; they shall be subsequently assembled one another by means of bolts and machined again, in order to obtain the tolerances indicated in the drawings and in chapter 9.0.
The AZIMUTH FRAME is the main component of the telescope, which transfers the loads from the elevation structure down to the Azimuth ring structure through the hydraulic axial pads.
The AZIMUTH FRAME includes the central bearing support to contain the radial loads on the Azimuth axis, and the lateral hydraulic pad supports to contain the axial loads on the Elevation axis.
The following main components are installed on the AZIMUTH FRAME:
Moreover, an Azimuth platform and stairs for access and maintenance are placed on the AZIMUTH FRAME.
The box structure of the AZIMUTH FRAME provides for openings for the plants crossing and access to the components for disassembly and maintenance purposes.
The AZIMUTH FRAME and CENTRAL BEARING SUPPORT (see dwg. No. 421e037) are interfaced with the following elements:
All above mentioned interfaces are indicated in the drawings listed in dwg. No. 430e007. All drillings and machining requested in the pertinent interface drawings shall be arranged for.
(*) the interfaces with those subsystems are not included in the present Technical Specification and will be prepared in the occasion of the pre-erection.
5.0 PERFORMANCE CHARACTERISTICS
The main performance characteristics of the AZIMUTH FRAME are the following:
6.0 RELIABILITY, MAINTAINABILITY REQUIREMENTS
The useful lifetime of the telescope is expected to exceed 25 years.
The contractor shall take into account of all aspects which could limit the lifetime of the supply.
He shall also contain the number of maintenance interventions, supply adequate access for maintenance operations and minimise risks of damage, loss and injury to personnel and the telescope from telescope maintenance operations.
This chapter defines the natural and induced environmental conditions the telescope and subassemblies will encounter during its lifetime.
8.0 DESIGN AND CONSTRUCTION REQUIREMENTS
Scope of the present chapter is to introduce the main characteristics of the supply from a manufacturing point of view.
The contractor shall take care of confirming the adopted criteria or propose alternative solutions, in order to obtain the requested performances.
The contractor shall fabricate all parts, equipment, components and materials of the AZIMUTH FRAME STRUCTURE and CENTRAL BEARING SUPPORT in accordance with the requirements indicated in the present Technical Specification, pertinent drawings and Proposal documents.
Subsequent to fabrication, but prior to packaging the materials, the contractor shall store, at its sole expenses, all components, materials and equipment in manner that will reasonably protect such components, materials and equipment against loss or damage.
Suitable allowances for contractor and expansion during welding shall be made in the lengths of the steel parts prior to welding, so that final machined lengths are correct within the acceptance tolerances specified in this Technical Specification and relative drawings. Welding procedures shall be such that distortion and lock-up stresses are minimised. Tack welds, temporary stiffeners, tie bars, controlled peening, pre-heating and stress relieving during welding may be used for this purpose, as approved by P.O..
Surface to be welded shall be dry, clean and free for loose scale, grease, or unsuitable protective paints or coatings.
All welded parts and assemblies, unless specified or approved otherwise by P.O., shall be fully stress relieved prior to final machining operations. Stress relieving shall be accomplished by the heat treatment method in a chamber with sufficient volume and temperature capacity to fully stress-relieve the welded parts and subassemblies.
The contractor shall foresee on all structures of the AZIMUTH FRAME some communication drillings, to be defined with the P.O., among the various elements and inside each element in order to allow the air flow of the telescope's air conditioning system.
The general dimensions of the AZIMUTH FRAME STRUCTURE are shown in dwg. No. 430e007.
Maximum dimensions: length 12150 mm
Total weight: 146738 kg
Lifting points: t.b.d. with the contractor
The materials are indicated in the drawings and relative Part Lists.
STEEL PLATES: Fe 430C UNI EN 10025
Steel plates relevant to surfaces to be further machined shall be supplied with complete Ultrasonic Examination Certificates, according to UNI EN 160/87 or ASME SA-578, acceptance standard level I.
All welding operation shall conform to the standards set forth in American Welding Society Specification AWS D1.1 or equivalent approved by P.O..
Welding operations shall be performed in such a way as to guarantee the following mechanical machining in terms of tolerances, as indicated on drawings. For this purposes, welding procedures shall consider possible shrinkages or expansions during welding operation and minimise the distortion and lock-up stresses.
The contractor shall perform and provide trial welds to demonstrate the soundness of any proposed welding method, and the competence of any person performing welding work, as required by P.O. at any time.
(Butt Joints Complete Penetration:
Class I according to UNI 10011, UNI 11001 and UNI 1307/2.
NDT: X-ray or Ultrasonic examination; acceptance criteria as required for above mentioned class of welding, according to UNI 7278, or welding procedures tests according to EN 288-3.
| Welding material | electrode: | according to UNI 5132: Class IVB or according to AWS A5.1: E 7018-1 |
| wire: | according to AWS A5.20: E 80T5/G | |
Class II according to UNI 10011, UNI 11001 and UNI 1307/2.
NDT: X-ray or Ultrasonic examination; acceptance criteria as required for above mentioned class of welding, according to UNI 7278, or welding procedures tests according to EN 288-3.
| Welding material | electrode: | according to UNI 5132: Class IVB or according to AWS A5.1: E 7018-1 |
| wire: | according to AWS A5.20: E 80T5/G | |
Construction: according to UNI 10011, UNI 11001 and UNI 1307/2.
NDT: Magnaflux 60% examination, acceptance criteria category II as per UNI 7278 par.A.4.3.
| Welding material | electrode: | according to UNI 5132: Class IVB or according to AWS A5.1: E 7018-1 |
| wire: | according to AWS A5.20: E 80T5/G | |
For welded parts: CNR UNI 10011 and UNI 11001.
Tolerances for linear and angular dimensions are specified on relevant drawings. These tolerances are mandatory, for structure acceptance. Where not specified, ISO 2768 part 1/m and 2/k shall be applied.
Complete stress relieving.
Parameters: t.b.d. with the contractor.
All metallic surfaces, other than rating machining surfaces shall be painted, coated or otherwise permanently protected against atmospheric corrosion.
At a minimum all paints and coatings shall provide for the following functional requirements:
The contractors shall utilise the following paint system in performance of the work.
The supplier can propose an alternative painting cycle; in any case this shall be able to guarantee the above mentioned requirements.
The contractor will present, in a detailed way, the following documents:
Particular attention shall be paid to the machining of the Elevation drive system's housings mentioned in dwg. No. 460a010.
Note: the overmetal indicated on the fabrication of the steel works requires an accurate fabrication (carpentry dimensional tolerances 5÷8 mm). It is up to the contractor to maintain them or to modify them, in order to ensure the successive mechanical machining and relative tolerances. Any modification must be approved by the P.O.
The AZIMUTH FRAME elements shall be pre-assembled for the completion of the machining, to verify the total dimensions and pertinent tolerances indicated on the drawings.
Before disassembling for shipment, all couplings shall be opportunely locked by a pin.
The eventually required special tooling to perform the assembly and the alignment is part of this Contract supply.
The supply excludes both packing and transport activities.
The contractor shall give assistance with personnel and means during all operation of packing and charge for transportation and shall provide at his own expenses, for stocking in an appropriate place of the material, waiting to be packed and shipped.
The contractor shall prepare and submit to the P.O. the Acceptance Test Plan.
The following tests and inspections shall be performed prior to Plant Acceptance, and shall be included in the Acceptance Test Plan:
(Not applicable).
Doc_info_start
Title: AZIMUTH FRAME STRUCTURE & CENTRAL BEARING SUPPORT
Document Type: TECHNICAL SPECIFICATION
Source: EIE
Issued by: G.MARCHIORI
Date_of_Issue: 04/08/97
Revised by:
Date_of_Revision:
Checked by:
Date_of_Check:
Accepted by:
Date_of_Acceptance:
Released by:
Date_of_Release:
File Type:MS-WORD 6
Local Name: C0301/DOC/401e026d.doc
Category: TELESCOPE AZIMUTH PLATFORM
Sub-Category: GENERAL TELESCOPE
Assembly: TELESCOPE TECHNICAL DOCUMENTS
Sub-Assembly:AZIMUTH FRAME STRUCTURE & CENTRAL BEARING SUPPORT
Part Name:
CAN designation: 401e026
Revision: d
Doc_info_end