Frequently Asked Questions

For Industrial bushing applications, beyond ambient conditions (such as the presence of oil, solvent or excess heat), the most important factors to consider in designing your bushing, are the physical and mechanical requirements of the application.

Static Radial load capacity for a three piece “silent bloc” bushing is typically rated at 600 psi. If you are experiencing premature failures with a “silent bloc” bushing, a Center Bonded Bushing of the same size, can often solve the problem. Because the rubber or neoprene overmold, is bonded to the O.D. of the insert, it has a greater radial load capacity (Static Radial load capacity of 1,000 psi), than a three piece bushing.

Additionally a Center Bonded Bushing will typically provide a more consistent spring rate, than the silent bloc bushing, because the rubber overmold size is produced from a consistently sized mold, rather than manually cut to size.

Additionally, torsional testing performed on three piece “silent bloc” bushings, shows that in some cases the silent bloc bushings will not retain their torsional properties, after warm-up.

For On Highway bushing applications, ambient conditions (particularly excess heat) is an important consideration for parts used in under hood applications, higher volumes typically push decisions toward lower cost alternatives. Fully mold bonded bushings are often used, but because the rubber is left in tension, they do not typically provide extended life cycles. A swaging or pre-stressing process is recommended for the finished bushing to add compression, but typically requires a second set of tooling and separate manufacturing operation to accomplish the pre-stress function. While a bit more expensive, the swaging process (described above) provides a more durable reliable part, with the addition of compression.

The post mold bonding process is commonly used on large undercarriage parts, and can improve durability, but also requires additional manufacturing steps, (application of primer and adhesive) and an oven, or other tooling equipment (coil) to flux the primer and adhesive.

When properly designed both silent-bloc, and center joint bonded bushings accommodate oscillating movement without lubrication in dusty and dirty environments, they relieve mis-alignment, reduce noise, and absorb linear and torsional vibration.

Which design you choose is dependent on your budget and technical needs.

Silent-Block Design

Silent-Bloc Bushings generally consist of three distinct pieces. An outer steel sleeve and an inner steel sleeve, which sandwiches a piece of molded rubber (a “shot” bushing). Or a long rubber tube assembled over a steel inner tube, which is funneled into an outside steel tube and cut to length (a “Torflex” bushing).

The Silent-Bloc or Torflex Bushings described above rely on a mechanical bond-compression-and friction between the rubber and metal sleeves for adhesion. The main benefit of the Silent-Block Design is as follows:

• Good low cost (no rubber mold tooling expense) when fabricated from existing rubber mold tooling

Center Joint Bonded Design

Center Joint Bonded Bushings have the rubber vulcanized to the insert. This chemically bonded over mold, is then assembled into the outer sleeve. Initial tooling costs can be slightly higher for the rubber mold, but with volume applications, this cost is typically minimized. Benefits from Center Joint Bonded Design include:

• Additional radial load capacity
• Tighter tolerances can be maintained
• Greater fatigue life

Yes we can. We offer free product design assistance with no obligation quotes.

Yes we do.

Bushings Inc. is happy to assist potential customers in troubleshooting performance problems.  Typically with the customers answers to a few simple questions we can help diagnose the root cause of the bushing problem in the application, and come up with a solution.  A sample part is sometimes requested to assist in the analysis.  

Some of the most common problems experienced are:

• High heat (this can be either ambient temperature, or the heat generated by the mechanical work being done in the application)
• Overloading (part size is insufficient for the load being carried)
• Ambient conditions (such as the presence of oil, solvent or lube in the application)
• Improper method of manufacture – (part not manufactured using the optimum method of manufacture for the duty cycle which the part sees in the application)

Yes we do. If you have a single piece or small batch requirement, you and your order will receive prompt, professional, and personalized service.

Yes, we are ISO Certified Manufacturer of “Rubberflex” – Metal Clad Rubber Insulated Bushings, and “Dual-Flex” – Marine / Industrial Engine Mounts.

Our quality system is ISO 9001:2015 certified and has been since 2002. We maintain a fully equipped Quality Control Lab – staffed with trained and qualified, technicians. We are proud of the fact that our attention to quality has enabled us to attain “Dock-to-Stock” status with many of our Original Equipment Manufacturer jobs.

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Unless otherwise noted:

Our quotation are valid for thirty (30) days from date of issue.
Orders accepted by us are not subject to cancellation nor is the work subject to delay by buyer except with our handwritten consent on satisfactory terms.

It is not our intention to manufacture any product that may be construed as a patent infringement, or to violate a non-compete clause, if it appears one of these conditions may occur, we reserve the right to withdraw our quotation. Buyer agrees to fully protect Bushings Inc. against litigation or damages, pertaining to above, particularly parts made to buyer’s specifications.

Parts manufactured by us are warranted to be free from defect, but are not guaranteed for any specific length of time or measure of service.

Due to the difficulty of manufacturing an exact quantity ordered, a shortage or excess in count varying not more than 10% from the quantity ordered will be accepted.

A separate charge may be incurred to compensate for any tax, excise, tariff, duty, or levy now or hereafter enacted or imposed by any government authority which we may be required to pay pursuant to an order.

Daily interest commensurate with the prime rate, is to be collected if an account is carried past due. Open orders may be cancelled or delayed if the ability of the buyer to discharge debt, becomes questionable at any time.

The failure on our part to enforce strict performance of the above terms and conditions shall not be deemed as a waiver of these terms and conditions.