1. Is it okay for a Permaswage fitting to be installed to some partially painted tube?
A: We do not recommend swaging painted tubing with any of our fittings. The paint may be damaged due to the swage and it may act like a stress riser and lead to fretting tube failure.
2. What is the part number of the hydraulic fluid of the pump?
3. What is the main cause of the leakage when operating the relief valve?
A: There should not be leaking at the relief valve. It may be stripped and need repair.
4. The pump cannot reach 10,000 psi, but it can exceed 9,000 psi. Is that normal? What is the minimum pressure that would be available for manual operation?
A: Operation of the pump should be 10,000 psi (+/- 250 psi). Any pressure less than 10,000 psi is not acceptable.
5. What systems have DME been used on?
A: Predominately used on hydraulic applications, DME is well suited for any systems that fall within the operating pressure, temperature ranges, and compatible tubing alloys/wall thicknesses called out in the SOP604-013.
6. Is the installation tooling the same for DME40 and DME30 fittings?
A: Tooling would be the same.
7. In addition to minimum straight length, are there tooling constraints that need to be considered in tubing design for DME tooling?
A: Since the majority of installations of DME are bench/production, there should be no installation access issues with DME tooling. Also, there should be no issues with tools as they relate to tubing design other than minimum straight length to bend.
8. Why does DME30 not qualify as AS18280 and part of the QPL?
A: DME30 is made from a material that is not listed in AS18280; therefore, it does not fall under the full scope of AS18280. On the other hand, it is not an industry standard to be part of any QPL.
9. Why are MS21922 and NAS1760 described as "interchangeable"? Did you compare the dimensions of those two standards?
A: DME30 is interchangeable functionally with both fittings, but the dimensions of three fittings are different. Their dimensions cannot be compared because NAS1760 is a machined end, and MS21922 and DME30 require special assembly procedure or swaging. However, the tube stick-out of both MS21922 and DME30 (when using the proper dies) returns the same distance from the gage dimension on the fitting to the end of tubing, and it provides the same assembly without changing the overall tube length.
10. Can you provide more information on the blue paint used as finish inside the fitting?
A: It is Teflon-based PTFE paint that is used mainly for identification and to direct the user in the proper installation of the tooling for swaging.
11. Do the ARP908 torque values apply for the MS and AS nuts?
12. Does ARP908 specify the torque values based on the tubing material or the fitting material?
A: ARP908 is for hose and tube fittings; however, it specifies that if any component of the joint is aluminum, the values for aluminum fitting Material II shall apply.
13. Is re-swaging possible on the DME system?
14. What is a DLT power unit?
A: A DLT power unit is a hydraulic cylinder that converts the pump pressure into the swaging force of the head assembly. The power unit consists of various components, including a piston, springs, and hydraulic seals.
15. What is the head assembly?
A: The head assembly consists of a lower die block, yoke, end plates, and swage dies. The head assembly is available in graduated sizes for the different sizes of fittings of the power unit model, as applicable.
16. What types of pumps does Permaswage offer?
A: Permaswage offers pneumatic, electric, and manual.
17. What are tube deburring tools?
A: The deburring tools are equipped with size-dependent, removable stem assemblies for the various tube sizes. Each tool has an expandable rubber plug to fit a range of tubing walls. The plug prevents metal chips from contaminating tubing systems during the deburring process.
These tools are included in kits with units up to model 40.
18. What are tube cutters?
A: The tube cutters are equipped with a ratcheting handle, making it possible to cut a tube when space limitations make it impossible to move the handle through a wide arc. Tube cutters range in size from 3/16” to 1-1/2".
19. What are tube installation marking templates?
A: Tube installation marking templates are used to establish the proper installation depths.
20. What are after-swage inspection gages?
A: After-swage inspection gages are used to verify that the proper amount of swage was achieved.