ED0039521 A- PIP-II CDS tunnel warm piping Spec for relief vent expansion joints.pdf

PIP-II Cryogenic Distribution System

Specifications for the axial expansion bellows on cryomodule relief vent headers

Document number: ED0039521

Fermi National Accelerator Laboratory 2

Document Approval Signatures Required Date Approved

Originator: William Soyars and Ram Dhuley, Cryogenics Engineers As in Teamcenter

Approver: Ram Dhuley, CDS L3 Manager As in Teamcenter

Revision History

Revision Date of Release Description of Change

- 11/20/2024 Original release A 1/23/2025 • Add flow requirement and direction as Serial Numbers 6 &

7 to Table 1 and Table 2.

• Add liner cleanliness requirements as Serial Number 12 to

Table 3.

Fermi National Accelerator Laboratory 3

Table of Contents

Introduction

Requirements for the axial expansion bellows

Specifications for the bellows, general

What to provide with proposal

Fermi National Accelerator Laboratory 4

Introduction

The Proton Improvement Plan II (PIP-II) is a particle accelerator being built at Fermilab. The accelerator includes cryogenically cooled superconducting radio frequency cavities using liquid helium (He II) at 2 K.

The cavities and their He II baths are housed in cryomodules (CMs). There are multiple accidental scenarios that can lead to vaporization of He II and subsequent rapid pressurization of the He II baths. For ensuring safety during such scenarios, a pressure relief system is provided for the PIP-II accelerator. The pressure relief system has two sets of header pipes each over a length of ~260 m, a snippet of this is presented in Figure 1a. Following a helium CM relief event, these header pipes accept cold helium gas from the CM and transport the venting flows out of the accelerator tunnel.

Axial bellows are needed at regular intervals on the header pipes to compensate for thermal contraction during a relief event. Figure 1b presents a generic bellows planned for installation on the header lines. The majority of the piping is 8 inch (DN200), with a small portion being 10 inch (DN250).

Figure 1: Schematics of part of the PIP-II cryomodule relief header piping (a, left) and representative bellows planned for installation on the relief headers (b, right).

Requirements for the axial expansion bellows, specific to size

The 8-inch (DN200) and 10-inch (DN250) bellows specifications are presented in Table 1 and Table 2, respectively.

Fermi National Accelerator Laboratory 5

Table 1: Specifications for the 8 inch (DN200) Vent Header axial expansion joint.

Sr. No. Item Item specification 1 Pipe size of relief header 8-inch Sch 10 2 Bellows end-connection type, typical of both ends Butt-weld. To include v-groove preparation.

3 Overall Length including ends, approximate

16 in (410 mm). Please provide actual overall length with proposal.

4 Axial displace requirement, from neutral

+ 70 mm.

5 Orthogonal Envelope size constraint

The 8-inch (DN200) bellows fully assembled with tie-rods should fit inside a 11 x 11 inch (279 x 279 mm) envelope

6 Flow requirements Helium gas. Peak velocity 150 m/s at temperature 290 K.

Flow duration 10 sec. Assume occurs once every 2 years, during 20-year lifespan.

7 Flow direction Bi-directional flow. Design to handle short duration high velocity in either direction, utilizing methods such as bi-directional internal liner or sleeve, or multi-ply bellows to increase stability, or other suitable methods. Please describe approach with proposal.

7 Quantity 24

Table 2: Specifications for the 10 inch (DN250) Vent Header branch expansion joint.

Sr. No. Item Item specification 1 Pipe size of relief headers 10-inch Sch 10 2 Bellows end-connection type, typical of both ends Butt-weld. To include v-groove preparation.

3 Overall Length, approximate 16 in (410 mm). Please provide actual overall length with proposal.

4 Axial displace requirement, from neutral

+ 70 mm.

5 Orthogonal Envelope Size constraint

The 10-inch (DN250) bellows fully assembled with tie-rods should fit inside a 14 x 14 inch (356 x 356 mm) envelope.

6 Flow requirements Helium gas. Peak velocity at expansion joint 150 m/s at temperature 290 K. Flow duration 30 sec. Assume occurs once every 5 years, during 20-year lifespan.

7 Flow direction Single direction flow. Design to handle short duration high velocity in one direction, utilizing methods such as internal liner or sleeve, or multi-ply bellows to increase stability, or other suitable methods. Please describe approach with proposal.

7 Quantity 3

Fermi National Accelerator Laboratory 6

Requirements for the axial expansion bellows, general

The general specifications for both 8 inch (DN200) and 10 inch (DN250) bellows are presented in Table 3.

Table 3: Common Specifications for the vent header branch expansion joints (DN200 and DN250).

Sr. No. Item Item specification 1 Material Both the flexible part and end pieces shall be made of stainless steel: 316 or 304 2 Internal pressure range Minimum pressure: -1 bar gauge (vacuum)

Maximum pressure: 3.1 bar gauge 3 Nominal pressures Internal: 0.2 bar gauge

External: 1 atm 4 Temperature Maximum temperature = 310 K

Minimum design metal temperature = 20 K 5 Restraint Integrated tie-rod assembly designed to withstand forces due to vacuum and pressure given in item 2.

6 Axial movement required with tie-rod restraint, after assembly with header pipes

Under vacuum (-1 bar.g negative pressure): 0 mm contraction from natural length At MAWP (3.1 bar.g positive pressure): 70 mm expansion from natural length

7 Minimum number of cryogenic operation cycles

8 Code requirement and standards The design of the bellows should be checked using EJMA standards: Stress state, buckling, and fatigue should be checked. The expansion joint will be installed on a piping system and therefore must comply with

ASME B31.3.

9 Maximum helium gas leak rate < 1 x 10-9 mbar-L/sec 10 Pressure test Conduct test and provide pressure test certification in full compliance with ASME B31.3.

11 Manufacturing Cleanliness requirements Free of dirt, grease, oil, and chips.

12 In-service gas purity requirements Design must ensure air and other impurities can be removed when expansion joint installed in high purity helium system. If internal liner/sleeve(s) used in the expansion joint, sleeves must allow gas-communication for the volume trapped between the sleeves and bellows with the main process flow.

13 Shipping and handling requirements

Bellows must be restrained during shipment to prevent unintended oscillations/cycles.

Documentation requirements for the bellows

Fermi National Accelerator Laboratory 7

4.1 The following items shall be submitted in English with the proposal. Information considered proprietary should be identified as such.

Total cost to fabricate, test, and deliver to FERMILAB site the expansion bellows.

Delivery schedule.

Lists of exceptions to this specification and reasoning for exception.

Technical details:

• Drawing showing overall length, OD, ID, and envelope of the bellows with end connections and restraints.

• Full design allowance of axial expansion, if in excess of the stated requirements.

• Drawing showing approach to handling short duration, high velocity flow conditions as described. For bi-directional flow in 8-inch expansion joint. For single direction flow in 10-inch expansion joint.

• Drawing showing approach to ensuring in-service helium purity.

4.2 The following items shall be submitted at the time of delivery to FERMILAB.

Final quality control reports including, but not limited to, leak check and pressure test reports.

Completed manufacturing inspection plans.

Material certifications.

Nonconformances & their Resolution.

Certificate of Compliance to ASME B31.3.

Welding documentation, to include WPS, PQR, WQR.

Final detailed drawing of bellows.