Back-up Rings with PTFE, EPDM, NBR, FKM Materials

• Customization: Available
• Structure: Single End
• Pressure: Medium Pressure Mechanical Seals
• Model NO.: back-up rings
• Speed: General Speed Mechanical Seal
• Temperature: Temperature Mechanical Seal
• Performance: Temperature
• Standard: Standard
• Balance: Balanced
• Metal Bellow: Mfl85n Metal Bellow Seal
• Metal Bellow Mechanical Seal: Screw Pump Seal
• Mechanical Seal Replacement: Depac
• Water Pump Seal: Roten Seal
• Shaft Seal: Umbra Seal
• Centrifugal Pump: Seal
• Mechanical Seal: Mflwt80 Metal Bellows Seal
• Metal Bellow Core: Big Compressor Seal
• Bellow Mechanical Seal: Oil Pump Seal
• Transport Package: Neutral Packing or Customized
• Specification: all size
• Trademark: Trisun
• Origin: China
• HS Code: 84842000
• Production Capacity: 1, 000, 000

Product Description

Back-up rings with PTFE/Teflon, EPDM, NBR, Viton/FKM etc. materials:


Back-up rings or anti extrusion rings as they are sometimes called have been used for many years in conjunction with O-rings in high pressure applications.

A back-up ring is a rigid ring that holds an elastomeric seal to its designed shape and in its correct place. Back-up rings are most commonly used with O-rings to prevent extrusion at high pressures.

When sealing the piston inside a pneumatic cylinder, a soft and flexible material is required to prevent leakage, but those same properties may leave the seal material vulnerable to being pulled out of its seat and then pinched or torn in the narrow space between piston and cylinder wall. If the joint cannot be redesigned, or a more resistant elastomer used, then the solution may be direct reinforcement with a stiffer material - in the form of a hard inner ring in this case

In general terms, for dynamic applications over 100 bar, and static applications around 950 bar, back-up rings should be used. Each application can vary so you must check and use this as a general guideline only.
Traditionally PTFE has been used for these items, but in recent years contoured elastomer rings have been developed and are now very widely used. We hold large stocks of Contoured rings in both Nitrile and Viton®

Depending on the fitting arrangement either Solid, Split or Spiral PTFE rings are used, or the contoured alternative. We can supply which ever type you require.


Besides back-up rings, we also have all kinds of mechanical seals. 


Metal bellow seals are used for many chemical pumps, cryogenic pumps, screw pumps, oil pumps, NTT heating medium pumps, big compressors etc. industrial pumps. 

MB-B01 is equivalent to MFL85N metal bellow seal. 
Cartridge MFL85N/60 is used for NTT heating medium pumps. 
Cartridge MFLWT80/55 is used for high temperature and corrosive pumps. 









We have seals for SEFCO pump  Model No: C-19. Johnson pump, Roper  pump, Sulzer pump etc. brands. 

Our metal bellow seals equivalent to:
John crane: 670/680/676, 604, 606, 609, 5615, 5615Q, 5625, 1604, 2609, 3609, EZ1, 515E;
Eagle: MFL85N(F), MFLWT80, MFLCT80, MFL6, MTEX, TS700
Flowserve: CBR, BX, BXRH, X-100, X-200, ISC1BX, ISC2BB
AES: BASI, BDFC, BQFD, BSFG
Chesterton: 886HT, 186HT, 286. 


Trisun is a professional manufacturer of mechanical seals, metal bellow seals, cartridge seals, dry gas seals, mixer and agitator seals, sealing support system and OEM pump seals since 1998.

pls. check the following cross reference between our metal bellow seals and other brands.
If you need cross reference for other seals, pls. contact me.

	TYPE	JOHN CRANE	Eagle	FLOWSERVE	AES	CHESTERTON	OTHER
METAL BELLOW SEAL	MB-J01	670/680/676
	MB-J04	604
	MB-J05	606
	MB-J06	609
	MB-J07	5615
	MB-J08	5615Q
	MB-J09	5625
	MB-J10	1604
	MB-J11	2609
	MB-J12	3609
	MB-J13	EZ1
	MB-PZ02	515E
	MB-FS01			CBR
	MB-FS02			BX
	MB-FS03			BXRH
	MB-FS06			X-100
	MB-FS07			X-200
	MB-FS08			ISC1BX
	MB-FS09			ISC2BB
	MB-B01		MFL85N(F)
	MB-B03		MFLWT80
	MB-B04		MFLCT80
	MB-B05		MFL6
	MB-B06		MTEX
	MB-B07		TS700
	MB-C01					886HT
	MB-C02					186HT
	MB-C03					286
	MB-A01				BASI
	MB-A02				BDFC
	MB-A04				BQFD
	MB-A05				BSFG